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Distribution by Scientific Domains

Polymers and Materials Science	66%
Medical Sciences	33%

Selected Abstracts

Brittle-to-Ductile Transition in Uniaxial Compression of Silicon Pillars at Room Temperature

ADVANCED FUNCTIONAL MATERIALS, Issue 15 2009
Fredrik Östlund
Abstract Robust nanostructures for future devices will depend increasingly on their reliability. While great strides have been achieved for precisely evaluating electronic, magnetic, photonic, elasticity and strength properties, the same levels for fracture resistance have been lacking. Additionally, one of the self-limiting features of materials by computational design is the knowledge that the atomistic potential is an appropriate one. A key property in establishing both of these goals is an experimentally-determined effective surface energy or the work per unit fracture area. The difficulty with this property, which depends on extended defects such as dislocations, is measuring it accurately at the sub-micrometer scale. In this Full Paper the discovery of an interesting size effect in compression tests on silicon pillars with sub-micrometer diameters is presented: in uniaxial compression tests, pillars having a diameter exceeding a critical value develop cracks, whereas smaller pillars show ductility comparable to that of metals. The critical diameter is between 310 and 400,nm. To explain this transition a model based on dislocation shielding is proposed. For the first time, a quantitative method for evaluating the fracture toughness of such nanostructures is developed. This leads to the ability to propose plausible mechanisms for dislocation-mediated fracture behavior in such small volumes. [source]

Inside Front Cover: Novel Engineered Ion Channel Provides Controllable Ion Permeability for Polyelectrolyte Microcapsules Coated with a Lipid Membrane (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 2 2009
Mater.
In their Full Paper on page 201, Donald Martin and co-workers describe the covering of polyelectrolyte microcapsules with a lipid bilayer that incorporates a novel engineered ion channel to provide a functional capability to control transport across the microcapsule wall. The cover image shows atomic-force microscopy images of these 8-layer polyelectroctrolyte capsules recorded using tapping mode in an aqueous environment. The capsules can be seen to collapse in a folded manner, with an occasional wrinkle that "absorbs" the extra surface area when flattening the spherical surface. [source]

Cover Picture: Colloidal Synthesis of Hollow Cobalt Sulfide Nanocrystals (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 11 2006
Mater.
Abstract Hollow nanocrystals have been synthesized through a mechanism analogous to the Kirkendall Effect. When a cobalt nanocrystal reacts with sulfur in solution, the outward diffusion of cobalt atoms is faster than the inward diffusion of sulfur atoms through the sulfide shell. The dominating outward diffusion of cobalt cations produces vacancies that can condense into a single void in the center of the nanocrystal at high temperatures. This process provides a general route to the synthesis of hollow nanostructures of a large number of compounds and is described in the Full Paper by A.,P. Alivisatos and co-workers on p.,1389. Formation of cobalt sulfide hollow nanocrystals through a mechanism similar to the Kirkendall Effect has been investigated in detail. It is found that performing the reaction at >,120,°C leads to fast formation of a single void inside each shell, whereas at room temperature multiple voids are formed within each shell, which can be attributed to strongly temperature-dependent diffusivities for vacancies. The void formation process is dominated by outward diffusion of cobalt cations; still, the occurrence of significant inward transport of sulfur anions can be inferred as the final voids are smaller in diameter than the original cobalt nanocrystals. Comparison of volume distributions for initial and final nanostructures indicates excess apparent volume in shells, implying significant porosity and/or a defective structure. Indirect evidence for fracture of shells during growth at lower temperatures was observed in shell-size statistics and transmission electron microscopy images of as-grown shells. An idealized model of the diffusional process imposes two minimal requirements on material parameters for shell growth to be obtainable within a specific synthetic system. [source]

Cover Picture: Spectroscopic and Photophysical Properties of a Highly Derivatized C60 Fullerol (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 1 2006
Mater.
Abstract The photo-oxidative stress in aqueous milieus can readily be generated in the presence of newly synthesized highly derivatized fullerenes (fullerols) reported in the Full Paper by Vileno and co-workers on p.,120. Their basic structural and photophysical properties were characterized using a range of methods, including X-ray photoelectron and IR spectroscopies, and electron spin resonance. Moreover, a significant drop of the local stiffness of a living cell was monitored using atomic force microscopy. This cell softening was attributed to the early effects of the photo-oxidative stress. Hydroxylated C60 molecules, also called fullerols, are a class of water-soluble fullerenes. Here we report the synthesis in acidic conditions of a highly derivatized fullerol (up to 36 carbons per C60 are oxidized). Spectroscopic investigations (X-ray photoelectron spectroscopy and infrared absorption) highlight the coexistence of both acidic and basic forms for the hydroxyl addends of derivatized C60. pH titrimetry reveals that, at millimolar concentrations, only ten protons per fullerol molecule are labile. Such a low value, as compared to 36 hydroxyl groups, is explained by the formation of clusters. A UV-vis absorption study performed over a large range of concentrations also points to the aggregation phenomenon. Moreover, this study shows that the clusters of fullerols appear at relatively low (micromolar) concentrations. An electron spin resonance (ESR) study, based on the attack of singlet oxygen (1,g) on 2,2,6,6-tetramethyl-4-piperidinol (TMP-OH), has proved the potential of hydroxylated C60 for performing efficient generation of singlet oxygen in aqueous solution. ESR measurements, which allow detection and quantification of 1,g, have also revealed the generation of reactive oxygen species (ROS). The yield of generation of 1,g and ROS is strongly correlated to the concentration of fullerol, thus also pointing to the aggregation of fullerol molecules. Exposing glioblastoma cells to oxidative stress in the presence of hydroxylated C60 and visible light has also been performed. Atomic force microscopy is used to monitor the relevant diminishment of the Young's modulus values for cells exposed to the oxidative stress. These results point to a possible application field of fullerols for performing bio-oxidations. [source]

Rheological Investigation of Shear Induced-Mixing and Shear Induced-Demixing for Polystyrene/Poly(vinyl methyl ether) Blend

MACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 9 2004
Samy A. Madbouly
Abstract Full Paper: The phase behavior of polystyrene (PS) and poly(vinyl methyl ether) (PVME) blend has been investigated rheologically as a function of temperature, composition and oscillating shear rate as well as different heating rates. An LCST (lower critical solution temperature)-type phase diagram was detected rheologically from the sudden changes in the slopes of the dynamic temperature ramps of G, at given heating and shear rate values. The rheological cloud points were dependent on the heating rate, , and oscillating shear rate, . The cloud points shifted a few degrees to higher temperatures with increasing and reached an equilibrium value (heating rate independent) at ,°C/min. The phase diagrams of the blends detected at ,=,0.1 and 1 rad/s were located in lower temperature ranges than the quiescent phase diagram, i.e., oscillating shear rate induced-demixing at these two values for the shear rate. On the other hand, at ,=,10 rad/s, the phase diagram shifted to higher temperatures, higher than the corresponding values found under quiescent conditions, i.e., shear induced-mixing took place. Based on these two observations, shear induced-demixing and shear induced-mixing can be detected rheologically within a single composition at low and high shear rate values, respectively, and this is in good agreement with the previous investigation using simple shear flow techniques. In addition, the William, Landel and Ferry (WLF)-superposition principle was found to be applicable only in the single-phase regime; however, the principle broke-down at a temperature higher than or equal to the cloud point. Furthermore, different spinodal phase diagrams were estimated at different oscillating shear rates based on the theoretical approach of Ajji and Choplin. Spinodal phase diagrams at different oscillating shear rates. [source]

Front Cover: Plasma Process.

PLASMA PROCESSES AND POLYMERS, Issue 4-5 2006
Polym.
Front Cover: Organosilicon plasma polymer thin films undergo modifications as they are exposed to an oxygen plasma. Under well chosen oxygen plasma conditions, they can even be converted into SiO2 -like films as shown by FTIR transmission spectra and X-ray reflectometry measurements. Further details can be found in the Full Paper by A. Granier*, G. Borvon, A. Bousquet, A. Goullet, C. Leteinturier, and A. van der Lee on page 365. [source]

Cover Picture: Plasma Process.

PLASMA PROCESSES AND POLYMERS, Issue 3 2006
Polym.
Cover: Plasma polymerized films undergo ageing processes when they are exposed to ambient air. The surface of a really fresh film can be studied when the reactor is online with analytical instruments, such as X-ray photoelectron or absorption spectrometers as well as Time-of-Flight SIMS. Allyl amine plasma polymers deposited at varied plasma parameters were thoroughly investigated using this approach. Further details can be found in the Full Paper by U. Oran,* S. Swaraj, A. Lippitz, and W. E. S. Unger on page 288. [source]

Cover Picture: Plasma Process.

PLASMA PROCESSES AND POLYMERS, Issue 2 2006
Polym.
Cover: AFM scans (5µm,×,5µm) of 500 nm thick films as deposited on Si from processes a) RFICP (full vertical scale: 12.6 nm), b) MIRA (full vertical scale: 44.9 nm), and c) DECRP (full vertical scale: 27.7 nm). Further details can be found in the Full Paper by P. Supiot,* C. Vivien, A. Granier, A. Bousquet, A. Mackova, D. Escaich, R. Clergereaux, P. Raynaud, Z. Stryhal, and J. Pavlik on page 100. [source]

Cover Picture: Plasma Process.

PLASMA PROCESSES AND POLYMERS, Issue 1 2006
Polym.
Cover: The picture on the cover shows axial, time-dependent distributions of (a) total light emission intensity, and [(b) to (d)] those of spectral lines at (b) 380.5 nm (N2), (c) 391.4 nm (N2+), and (d) 706.5 nm (He I), during the positive voltage half-cycle of an atmospheric-pressure He discharge across a needle-plane gap. Needle position at 3.0 mm, alumina dielectric plane at 0 mm. Further details can be found in the Full Paper by V. Poenariu, M. R. Wertheimer,* and R. Bartnikas on page 17. [source]

Cover Picture: Plasma Process.

PLASMA PROCESSES AND POLYMERS, Issue 9 2005
Polym.
Cover: Density functional theory was applied to study the thermochemistry of methyl- and methoxymethylsilanes. Predicted bond dissociation energies of methoxymethylsilanes are plotted, and potential reaction pathways of trimethoxymethylsilane and H atom are illustrated with the thermodynamically favored silanol formation highlighted. Further details can be found in the Full Paper by T. B. Casserly and K. K. Gleason* on page 669. [source]

Cover Picture: Plasma Process.

PLASMA PROCESSES AND POLYMERS, Issue 8 2005
Polym.
Cover: The Figure shows the X-ray photoelectron spectra of the nitrogen 1s core levels and the near edge X-ray fine structure nitrogen K edge of plasma polymers and plasma co-polymers prepared from allylamine and mixtures of acrylic acid and allylamine. Molecular models of allylamine, acrylic acid and allylammonium acrylate salt are shown to illustrate the chemistry. This is shown on a background of a micrograph of melanocytes cultured on a plasma polymer coating. The micrograph has been artificially colourised. Further details can be found in the Full Paper by A. J. Beck,* J. D. Whittle, N. A. Bullett, P. Eves, S. Mac Neil, S. L. McArthur, and A. G. Shard on page 641. [source]

Front Cover: Plasma Process.

PLASMA PROCESSES AND POLYMERS, Issue 7 2005
Polym.
Front Cover: The regime of plasma polymerization can be described by the evaluation of the mass deposition rates depending on the specific energy delivered to the active plasma zone. Thus, plasma reactors with well defined geometries support this macroscopic approach, which was found to hold also for gas mixtures of polymerizable and non-polymerizable gases. Further details can be found in the Full Paper by D. Hegemann,* and M.-M. Hossain on page 554. [source]

Cover Picture: Plasma Process.

PLASMA PROCESSES AND POLYMERS, Issue 6 2005
Polym.
Cover: The pictures on the cover show PTFE-like structures produced by a supersonic jet of products of PTFE thermal decomposition down to the monomer state. The structures are obtained at different substrate temperatures: at 50,°C (top) and 300,°C (bottom). Further details can be found in the Full Paper by A. K. Rebrov,* R. S. Sharafudinov, A. V. Shishkin, and N. I. Timoshenko on page 464. [source]

Cover Picture: Plasma Process.

PLASMA PROCESSES AND POLYMERS, Issue 1 2005
Polym.
Cover: The effect of pressure in the surface modification of poly(ethylene terephthalate) fibers induced by SF6 plasma treatment is shown by atomic force microscopy images of (a) the untreated surface and of the fiber surface after 60 s long SF6 plasma treatment at (b) 0.05 mbar, (b) 0.20 mbar and (c) 0.40 mbar. The RF power was 105W; PET fabrics were plasma-treated at 7.5 cm from the RF antenna. Further details can be found in the Full Paper by R. Barni, C. Riccardi, E. Selli,* M. R. Massafra, B. Marcandalli, F. Orsini, G. Poletti, and L. Meda on page 64. [source]

Systematic review of post-treatment psychosocial and behaviour change interventions for men with cancer

PSYCHO-ONCOLOGY, Issue 3 2010
Hannah L. Dale
Abstract Objectives: The psychosocial impacts of a cancer diagnosis include reduced quality of life, poorer inter-personal relationships, hopelessness and mental illness. Worse outcomes, including mortality rates have been found for single men with cancer compared with women and partnered men. The aim of this systematic review was to examine the effectiveness of post-treatment psychosocial and behaviour change interventions for adult men with cancer, in order to inform the development of an intervention. A focus on single men was intended. Methods: Ten databases were searched via Ovid and Web of Science. Papers were systematically extracted by title, abstract and full paper according to the inclusion/exclusion criteria. Full papers were assessed by two authors. Inclusion criteria: participants at any stage of a cancer diagnosis, ,50% male and aged 18+; psychosocial and/or behavioural post-treatment interventions, using any format; a one,three level of evidence. Couple/carer/family interventions were excluded. Results: From 9948 studies initially identified, 11 were finally included in the review. They implemented cognitive behaviour therapy, hypnosis or psychoeducational interventions. All studies had some positive results, however, lack of reporting of intervention content and methodological issues limit the findings. No studies intervened with single men, and none provided comparative outcomes for marital status. Conclusions: Effectiveness of interventions was difficult to assess as, while all had benefits, their generalisability was limited due to methodological and reporting limitations. Improved reporting procedures are required to allow for replication. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Replacement versus repair of defective restorations in adults: resin composite

AUSTRALIAN DENTAL JOURNAL, Issue 3 2010
MO Sharif
Background:, Composite filling materials have been increasingly used for the restoration of posterior teeth in recent years as a tooth coloured alternative to amalgam. As with any filling material composites have a finite life-span. Traditionally, replacement was the ideal approach to treat defective composite restorations, however, repairing composites offers an alternative more conservative approach where restorations are partly still serviceable. Repairing the restoration has the potential of taking less time and may sometimes be performed without the use of local anaesthesia hence it may be less distressing for a patient when compared with replacement. Objectives:, To evaluate the effectiveness of replacement (with resin composite) versus repair (with resin composite) in the management of defective resin composite dental restorations in permanent molar and premolar teeth. Search strategy:, For the identification of studies relevant to this review we searched the Cochrane Oral Health Group Trials Register (to 23rd September 2009); CENTRAL (The Cochrane Library 2009, Issue 4); MEDLINE (1950 to 23rd September 2009); EMBASE (1980 to 23rd September 2009); ISI Web of Science (SCIE, SSCI) (1981 to 22nd December 2009); ISI Web of Science Conference Proceedings (1990 to 22nd December 2009); BIOSIS (1985 to 22nd December 2009); and OpenSIGLE (1980 to 2005). Researchers, experts and organizations known to be involved in this field were contacted in order to trace unpublished or ongoing studies. There were no language limitations. Selection criteria:, Trials were selected if they met the following criteria: randomized or quasi-randomized controlled trial, involving replacement and repair of resin composite restorations. Data collection and analysis:, Two review authors independently assessed titles and abstracts for each article identified by the searches in order to decide whether the article was likely to be relevant. Full papers were obtained for relevant articles and both review authors studied these. The Cochrane Collaboration statistical guidelines were to be followed for data synthesis. Main results:, The search strategy retrieved 279 potentially eligible studies, after de-duplication and examination of the titles and abstracts all but four studies were deemed irrelevant. After further analysis of the full texts of the four studies identified, none of the retrieved studies met the inclusion criteria and all were excluded from this review. Authors' conclusions:, There are no published randomised controlled clinical trials relevant to this review question. There is therefore a need for methodologically sound randomised controlled clinical trials that are reported according to the Consolidated Standards of Reporting Trials (CONSORT) statement (http://www.consort-statement.org/). Further research also needs to explore qualitatively the views of patients on repairing versus replacement and investigate themes around pain, anxiety and distress, time and costs. [source]

Effectiveness of interventions that assist caregivers to support people with dementia living in the community: a systematic review

INTERNATIONAL JOURNAL OF EVIDENCE BASED HEALTHCARE, Issue 2 2008
Deborah Parker BA, MSocSci
Executive summary Objectives, The objective of this review was to assess the effectiveness of interventions that assist caregivers to provide support for people living with dementia in the community. Inclusion criteria, Types of participants, Adult caregivers who provide support for people with dementia living in the community (non-institutional care). Types of interventions, Interventions designed to support caregivers in their role such as skills training, education to assist in caring for a person living with dementia and support groups/programs. Interventions of formal approaches to care designed to support caregivers in their role, care planning, case management and specially designated members of the healthcare team , for example dementia nurse specialist or volunteers trained in caring for someone with dementia. Types of studies, This review considered any meta-analyses, systematic reviews, randomised control trials, quasi-experimental studies, cohort studies, case control studies and observational studies without control groups that addressed the effectiveness of interventions that assist caregivers to provide support for people living with dementia in the community. Search strategy, The search sought to identify published studies from 2000 to 2005 through the use of electronic databases. Only studies in English were considered for inclusion. The initial search was conducted of the databases, CINAHL, MEDLINE and PsychINFO using search strategies adapted from the Cochrane Dementia and Cognitive Improvement Group. A second more extensive search was then conducted using the appropriate Medical Subject Headings (MeSH) and keywords for other available databases. Finally, hand searching of reference lists of articles retrieved and of core dementia, geriatric and psycho geriatric journals was undertaken. Assessment of quality, Methodological quality of each of the articles was assessed by two independent reviewers using appraisal checklist developed by the Joanna Briggs Institute and based on the work of the Cochrane Collaboration and Centre for Reviews and Dissemination. Data collection and analysis, Standardised mean differences or weighted mean differences and their 95% confidence intervals were calculated for each included study reported in the meta-analysis. Results from comparable groups of studies were pooled in statistical meta-analysis using Review Manager Software from the Cochrane Collaboration. Heterogeneity between combined studies was tested using standard chi-square test. Where statistical pooling was not appropriate or possible, the findings are summarised in narrative form. Results, A comprehensive search of relevant databases, hand searching and cross referencing found 685 articles that were assessed for relevance to the review. Eighty-five papers appeared to meet the inclusion criteria based on title and abstract, and the full paper was retrieved. Of the 85 full papers reviewed, 40 were accepted for inclusion, three were systematic reviews, three were meta-analysis, and the remaining 34 were randomised controlled trials. For the randomised controlled trials that were able to be included in a meta-analysis, standardised mean differences or weighted mean differences and their 95% confidence intervals were calculated for each. Results from comparable groups of studies were pooled in statistical meta-analysis using Review Manager Software and heterogeneity between combined studies was assessed by using the chi-square test. Where statistical pooling was not appropriate or possible, the findings are summarised in narrative form. The results are discussed in two main sections. Firstly it was possible to assess the effectiveness of different types of caregiver interventions on the outcome categories of depression, health, subjective well-being, self-efficacy and burden. Secondly, results are reported by main outcome category. For each of these sections, meta-analysis was conducted where it was possible; otherwise, a narrative summary describes the findings. Effectiveness of intervention type, Four categories of intervention were included in the review , psycho-educational, support, multi-component and other. Psycho-educational Thirteen studies used psycho-educational interventions, and all but one showed positive results across a range of outcomes. Eight studies were entered in a meta-analysis. No significant impact of psycho-educational interventions was found for the outcome categories of subjective well-being, self-efficacy or health. However, small but significant results were found for the categories of depression and burden. Support Seven studies discussed support only interventions and two of these showed significant results. These two studies were suitable for meta-analysis and demonstrated a small but significant improvement on caregiver burden. Multi-component Twelve of the studies report multi-component interventions and 10 of these report significant outcomes across a broad range of outcome measures including self-efficacy, depression, subjective well-being and burden. Unfortunately because of the heterogeneity of study designs and outcome measures, no meta-analysis was possible. Other interventions Other interventions included the use of exercise or nutrition which resulted in improvements in psychological distress and health benefits. Case management and a computer aided support intervention provided mixed results. One cognitive behavioural therapy study reported a reduction in anxiety and positive impacts on patient behaviour. Effectiveness of interventions using specific outcome categories, In addition to analysis by type of intervention it was possible to analyse results based on some outcome categories that were used across the studies. In particular the impact of interventions on caregiver depression was available for meta-analysis from eight studies. This indicated that multi-component and psycho-educational interventions showed a small but significant positive effect on caregiver depression. Five studies using the outcome category of caregiver burden were entered into a meta-analysis and findings indicated that there were no significant effects of any of interventions. No meta-analysis was possible for the outcome categories of health, self-efficacy or subjective well-being. Implications for practice, From this review there is evidence to support the use of well-designed psycho-educational or multi-component interventions for caregivers of people with dementia who live in the community. Factors that appear to positively contribute to effective interventions are those which: ,,Provide opportunities within the intervention for the person with dementia as well as the caregiver to be involved ,,Encourage active participation in educational interventions for caregivers ,,Offer individualised programs rather than group sessions ,,Provide information on an ongoing basis, with specific information about services and coaching regarding their new role ,,Target the care recipient particularly by reduction in behaviours Factors which do not appear to have benefit in interventions are those which: ,,Simply refer caregivers to support groups ,,Only provide self help materials ,,Only offer peer support [source]

Systematic review of post-treatment psychosocial and behaviour change interventions for men with cancer

Coxsackie B virus serology and Type 1 diabetes mellitus: a systematic review of published case-control studies

DIABETIC MEDICINE, Issue 6 2004
J. Green
Abstract Background Enteroviruses, in particular Coxsackie B4, have been implicated in the aetiology of Type 1 diabetes mellitus, but the epidemiological evidence has not been systematically evaluated. Methods Systematic review of evidence from published controlled studies of the relationship between Coxsackie B virus serology and incident or prevalent Type 1 diabetes mellitus. Studies were identified through a Medline search (1966 to 2002), supplemented by references from identified papers and hand search of relevant journals. All studies (full papers, abstracts or letters) with data adequate for calculation of unadjusted odds ratios (with 95% confidence intervals) for Type 1 diabetes mellitus in relation to Coxsackie B virus serology were included. Results The review included 26 case-control studies; no cohort study met the inclusion criteria. Odds ratios for Type 1 diabetes mellitus in serology-positive vs. serology-negative subjects ranged from 0.2 to 22.3. For Coxsackie B (any serotype) 7/13 studies had point estimates significantly greater than 1.0 (P < 0.05). For Coxsackie B3, Coxsackie B4 and Coxsackie B5-specific assays, 1/11, 6/17 and 1/11 studies, respectively, had point estimates significantly greater than 1.0. Summary odds ratios were not calculated because of doubts about the validity of individual study estimates, heterogeneity between studies, and the possibility of publication bias. Conclusions The results of these studies are inconsistent and do not provide convincing evidence for or against an association between Coxsackie B virus infection and Type 1 diabetes mellitus. Better designed studies using effective assays are needed to resolve this important issue. [source]

Effectiveness of interventions that assist caregivers to support people with dementia living in the community: a systematic review

Methodological issues in papers on IFN therapy: time for reappraisal

JOURNAL OF VIRAL HEPATITIS, Issue 3 2000
Kondili
We conducted an analytical review of 194 full papers on interferon (IFN) therapy for chronic hepatitis C to evaluate current methodology (i.e. study design, criteria for evaluating the efficacy of therapy and predictors of response). Of the papers evaluated, 64 were randomized controlled trials (RCT), 40 were non-randomized controlled trials (NRCT) and 90 were observational studies (OS). The methodological analysis was focused mainly on clinical trials. The number of patients enrolled in RCT was higher compared with the number enrolled in NRCT. Uniform enrolment criteria were used in less than 50% of the trials. Only 20% of RCT and 2.5% of NRCT used criteria for defining sample size. The response rate was calculated on an intention-to-treat basis in 36 of the RCT and in 14 of the NRCT. The outcome of treatment and the criteria employed to define the response to treatment were found to be far from standardized. In 51.5% of the RCT and 42.5% of the NRCT, normalization of alanine aminotransferase (ALT) level at the end of follow-up was the only marker of response studied. Only 57.6% of the trials considered histological evidence as an important outcome. Among the clinical trials, 71.1% evaluated predictors of good response to IFN therapy. In 51% of the OS, ALT normalization by the end of follow-up was the only criterion for defining response. In conclusion, to ensure a high level of reliability in comparing or combining the results of different studies, some basic general requirements must be followed when planning trials on antiviral therapy. [source]