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Selected AbstractsSigns and symptoms at diagnosis of amyotrophic lateral sclerosis: a population-based study in southern ItalyEUROPEAN JOURNAL OF NEUROLOGY, Issue 7 2006S. Zoccolella Amyotrophic lateral sclerosis (ALS) diagnostic criteria are used to select patients for clinical trials based on different levels of diagnostic certainty, according to the spread of upper (UMN) and lower motoneuron (LMN) signs in different anatomic regions. However, the clinical presentation of ALS patients is extremely variable and this can delay the time to diagnosis and decrease the likelihood for trial entry. The aims of the study were to describe the signs and symptoms of diagnosis in a population-based incident cohort of ALS cases, using the El Escorial (EEC) and the Revised Airlie Diagnostic Criteria (AHC). The source of the study was a prospective population-based registry established in Puglia, southern Italy, in 1997. The diagnosis and the classification of the cases were based on EEC and AHC. All incident ALS cases during the period 1998,1999 were enrolled and followed up. During the surveillance period, we identified 130 ALS incident cases, and bulbar-ALS represented 20% of our cohort. The highest risk for bulbar onset was among subjects aged >75 years [RR: 20.1, 95% confidence interval (CI) 3.4,118.0] compared with subjects aged <55 years and among females compared with males (Relative risk (RR): 2.75, 95% CI: 1,7.3). The vast majority of patients (72%) referred progressive muscle weakness in the limbs as the presenting symptom. Eighty percent of cases presented contemporary bulbar or spinal involvement; UMN signs in the bulbar region were present in 24% of cases and any motoneuronal sign in thoracic region in only 15% of the cases. In this population-based series, progressive muscle weakness was the most common presenting sign; bulbar onset was associated with advanced age and female sex. UMN signs in the bulbar region and any motoneuronal sign in the thoracic region were observed in 20% of our case series. This may represent the main limitation to show the spread of signs during diagnostic assessment for inclusion in epidemiological studies and clinical trials. [source] Cost-effectiveness analysis of two strategies for mass screening for colorectal cancer in FranceHEALTH ECONOMICS, Issue 3 2004Célia Berchi Abstract The implementation of colorectal cancer mass screening is a high public health priority in France, as in most other industrialised countries. Despite evidences that screening using guaiac fecal occult blood test may reduce colorectal cancer mortality, no European country has organised widespread mass screening with this test. The low sensitivity of this test constitutes its main limitation. Immunological tests, which provide higher sensitivity than the guaiac test, may constitute a satisfactory alternative. This study was carried out to compare the costs and the effectiveness of 20 years of biennial colorectal cancer (CRC) screening with an automated reading immunological test (Magstream) with those obtained with a guaiac stool test (Haemoccult). The model used to estimate the costs and effectiveness of successive biennial CRC screening campaigns was a transitional probabilistic model. The parameters used in this model concerning costs and CRC epidemiological data were calculated from results obtained in the screening program run in Calvados or from published results of foreign studies because of the lack of French studies. The use of Magstream for 20 years of biennial screening costs 59 euros more than Haemoccult per target individual, and should lead to a mean increase in individual life expectancy of 0.0198 years (i.e. about one week), which corresponds to an incremental cost-effectiveness ratio of 2980 euros per years of life saved. Our results suggest that using an immunological test could increase the effectiveness of CRC screening at a reasonable cost for society. Copyright © 2003 John Wiley & Sons, Ltd. [source] Degradative enzymatic activities in fresh-cut blood-orange slices during chilled-storageINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 5 2009Anna Eghle Catalano Summary Blood-orange fruits are suitable to fresh-cut fruit production because of their chemical compositions. Nevertheless, the main limitation of using freshly cut oranges is their susceptibility to juiciness loss and ascorbic acid degradation because of enzymatic alterations. The aim of this work is: to identify some of the enzymes causing the qualitative decay in blood-orange slices during 15 days of chilled storage (at 4 ± 0.5 °C and 85% RH); to investigate the susceptibility to the previous alterations of five blood-orange clones (Moro nucellare, Sanguinello nucellare, Tarocco arcimusa, Tarocco gallo and Tarocco meli) to select the most suitable one for fresh-cut production. The enzymes studied were: pectinmethylesterase (PME) as index of juiciness loss, ascorbate oxidase (AAO) as index of ascorbic acid's degradation and polyphenol oxidase (PPO) as browning index. As far as we know, the changes of AAO activity during chilled storage of blood-orange fresh-cut slices has not previously reported and studied. Different clones showed different enzymatic activities and quality changes during chilled-storage. In particular a low juiciness loss in orange slices was correlated with a lower PME activity, as described in T. meli clone, while a high degradation of ascorbic acid was correlated with an higher AAO activity, as described in T. gallo clone; PPO activity seemed to have no significant action in quality degradation. Tarocco meli was the most suitable clone to the fresh-cut blood-orange production because it has the lowest enzymatic activity (PME, PPO and AAO) and the highest sensorial quality. [source] Haemoglobinometry in general practiceINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 6 2003S. M. Lewis Summary Haemoglobinometry as a primary point-of-care test is well established. This study was undertaken to assess whether haemoglobinometry by itself provides an adequate haematological screening procedure in general practice. In a series of 500 sequential blood counts received by the central hospital laboratory from local doctors, 405 (81%) had a normal haemoglobin. Full blood counts on these samples showed 15% with one or more blood count parameters outside 2SD of normal reference values, including increased MCV, low MCV with low MCH and MCHC, leucocytosis with neutrophilia, a few cases with neutropenia, lymphopenia, monocytosis or eosinophilia. When the limits were set at 3SD, these abnormalities were found in only 7.6% of the cases. Calculation of test utility gave a positive predictive value of 0.83, a negative predictive value of 0.85, with a likelihood ratio of 14.3 and an overall diagnostic reliability of 84%. It was concluded that haemoglobin alone is a valuable primary screening test and a full blood count is required only when anaemia is present or when the patient's history and clinical signs indicate the need for such further investigation. Using this protocol it is unlikely that any serious error will be made in diagnosing a clinically significant condition; the main limitation is failure to diagnose pre-anaemic iron deficiency. [source] The empirical and theoretical base of family therapy and multiple family day therapy for adolescent anorexia nervosaJOURNAL OF FAMILY THERAPY, Issue 2 2005Ivan Eisler There is growing empirical evidence that family therapy is an effective treatment for anorexia nervosa, particularly in adolescence. This is in spite of the fact that the theoretical model from which most of the empirically based treatments are derived appears flawed. This paper provides a brief overview of the research evidence from treatment studies and studies of family functioning. It suggests that the main limitation of earlier theoretical models is their focus on aetiology rather than on an understanding of how families become organized around a potentially life-threatening problem. An alternative conceptual model is presented, and its application to family therapy and multiple-family therapy for adolescent anorexia nervosa is described. The treatment approach focuses on enhancing the families' own adaptive mechanism and mobilizing family strengths. [source] Treatment of recurrent hepatitis B infection in liver transplant recipientsLIVER TRANSPLANTATION, Issue 10B 2002Norah A. Terrault MD 1Therapeutic decisions are guided by a patient's clinical status (severity of disease and presence of comorbidities) and previous drug-exposure history. 2Lamivudine is safe and effective in liver transplant recipients with recurrent hepatitis B virus (HBV) infection caused by wild-type virus or failure of hepatitis B immunoglobulin therapy. Lamivudine resistance, developing in approximately 25% after 12 months of therapy, is its main limitation. 3Famciclovir is safe in liver transplant recipients; however, virological and clinical responses are less consistent than with lamivudine. Thus, lamivudine is favored over famciclovir as first-line therapy in transplant recipients with no previous exposure to nucleoside analogues. 4Although limited in availability, adefovir dipivoxil appears safe and effective in treating liver transplant recipients with lamivudine-resistant HBV disease. Close monitoring of renal function is recommended, with dose adjustment in patients with reduced creatinine clearances. 5Limited data suggest that intravenous ganciclovir, tenofovir disoproxil fumarate, and interferon alfa may be useful as rescue therapies for patients with lamivudine- or famciclovir-resistant HBV disease. 6Antiviral therapy with two or more suitable agents may minimize the chance for viral resistance; therefore, future therapeutic strategies likely will use combination therapy in the long-term management of recurrent HBV disease. [source] Sensitivity-encoded coronary MRA at 3TMAGNETIC RESONANCE IN MEDICINE, Issue 2 2004Michael E. Huber Abstract Long scan times are still a main limitation in free-breathing navigator-gated 3D coronary MR angiography (MRA). Unlike other MRI applications, high-resolution coronary MRA has not been amenable to acceleration by parallel imaging techniques due to signal-to-noise ratio (SNR) concerns. In the present work, mitigating SNR limitations by the transition to higher static magnetic field strength is proposed, thus enabling scan time reduction by the parallel sensitivity encoding (SENSE) technique. The study reports the implementation and evaluation of free-breathing navigator-gated 3D coronary MRA with SENSE at 3T. Results from 11 healthy subjects indicate that the approach permits significant scan time reduction in MRA of the left and right coronary systems. Quantitative image analysis and visual grading suggest that two-fold scan acceleration can be accomplished at nearly preserved image quality. The additional experiments appear to demonstrate that parallel MRA equally permits enhancing volume coverage and spatial resolution while maintaining scan time. Magn Reson Med 52:221,227, 2004. © 2004 Wiley-Liss, Inc. [source] On a third-order Newton-type method free of bilinear operatorsNUMERICAL LINEAR ALGEBRA WITH APPLICATIONS, Issue 4 2010S. Amat Abstract This paper is devoted to the study of a third-order Newton-type method. The method is free of bilinear operators, which constitutes the main limitation of the classical third-order iterative schemes. First, a global convergence theorem in the real case is presented. Second, a semilocal convergence theorem and some examples are analyzed, including quadratic equations and integral equations. Finally, an approximation using divided differences is proposed and used for the approximation of boundary-value problems. Copyright © 2009 John Wiley & Sons, Ltd. [source] The "Ductilities" in Single Phase Steels from Usual to Nanoscale MicrostructuresADVANCED ENGINEERING MATERIALS, Issue 10 2009Olivier Bouaziz Abstract The control and the improvement of the ductility of nanostructured structural steels is one of the key challenges in assessing the technological viability of this metallurgical strategy. In the present paper, it is shown that more rigorous definitions of the ductility are required in order to avoid possible confusions. After this preliminary work, a more transparent analysis is done concerning the effect of the microstructural scale showing clearly the weaknesses and the strengths of ultra-fine single phase steels. Finally, possible ways to overcome the main limitations are presented. [source] Nanocrystalline domain size distributions from powder diffraction dataJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2004Matteo Leoni The need for an a priori domain size distribution is one of the main limitations of existing line profile analysis methodologies. A numerical modification of the whole-powder-pattern modelling algorithm is proposed, to allow the refinement of a general domain size distribution from powder diffraction data. The shape of domains has to be inferred for the specimen under study. The algorithm is robust enough to unveil fine details in the refined distribution, as witnessed by the results of tests performed both on simulated and on real patterns of nanocrystalline ceria. [source] Photosynthetic limitations in olive cultivars with different sensitivity to salt stressPLANT CELL & ENVIRONMENT, Issue 4 2003F. LORETO ABSTRACT Olive (Olea europea L) is one of the most valuable and widespread fruit trees in the Mediterranean area. To breed olive for resistance to salinity, an environmental constraint typical of the Mediterranean, is an important goal. The photosynthetic limitations associated with salt stress caused by irrigation with saline (200 mm) water were assessed with simultaneous gas-exchange and fluorescence field measurements in six olive cultivars. Cultivars were found to possess inherently different photosynthesis when non-stressed. When exposed to salt stress, cultivars with inherently high photosynthesis showed the highest photosynthetic reductions. There was no relationship between salt accumulation and photosynthesis reduction in either young or old leaves. Thus photosynthetic sensitivity to salt did not depend on salt exclusion or compartmentalization in the old leaves of the olive cultivars investigated. Salt reduced the photochemical efficiency, but this reduction was also not associated with photosynthesis reduction. Salt caused a reduction of stomatal and mesophyll conductance, especially in cultivars with inherently high photosynthesis. Mesophyll conductance was generally strongly associated with photosynthesis, but not in salt-stressed leaves with a mesophyll conductance higher than 50 mmol m,2 s,1. The combined reduction of stomatal and mesophyll conductances in salt-stressed leaves increased the CO2 draw-down between ambient air and the chloroplasts. The CO2 draw-down was strongly associated with photosynthesis reduction of salt-stressed leaves but also with the variable photosynthesis of controls. The relationship between photosynthesis and CO2 draw-down remained unchanged in most of the cultivars, suggesting no or small changes in Rubisco activity of salt-stressed leaves. The present results indicate that the low chloroplast CO2 concentration set by both low stomatal and mesophyll conductances were the main limitations of photosynthesis in salt-stressed olive as well as in cultivars with inherently low photosynthesis. It is consequently suggested that, independently of the apparent sensitivity of photosynthesis to salt, this effect may be relieved if conductances to CO2 diffusion are restored. [source] Matrix Metalloproteinase 2 in Reduced-Size Liver Transplantation: Beyond the MatrixAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2010S. Padrissa-Altés We studied the contribution of matrix metalloproteinase 2 (MMP2) and matrix metalloproteinase 9 (MMP9) to the beneficial effects of preconditioning (PC) in reduced-size orthotopic liver transplantation (ROLT). We also examined the role of c-Jun N-terminal kinase (JNK) and whether it regulates MMP2 in these conditions. Animals were subjected to ROLT with or without PC and pharmacological modulation, and liver tissue samples were then analyzed. We found that MMP2, but notMMP9, is involved in the beneficial effects of PC in ROLT. MMP2 reduced hepatic injury and enhanced liver regeneration. Moreover, inhibition of MMP2 in PC reduced animal survival after transplantation. JNK inhibition in the PC group decreased hepatic injury and enhanced liver regeneration. Furthermore, JNK upregulated MMP2 in PC. In addition, we showed that Tissue inhibitors of matrix metalloproteinases 2 (TIMP2) was also upregulated in PC and that JNK modulation also altered its levels in ROLT and PC. Our results open up new possibilities for therapeutic treatments to reduce I/R injury and increase liver regeneration after ROLT, which are the main limitations in living-donor transplantation. [source] Facial transplantation as an option in reconstructive surgery: no mountains too high?ANZ JOURNAL OF SURGERY, Issue 12 2009Wojciech B, ogowski Abstract Background:, Human facial allotransplantation (FA) is a testament to the impressive progress, which was and is still happening in the field of transplantation medicine and reconstructive surgery. Like every pioneering treatment option, FA faces both the clinicians' and public opinion with a huge amount of medical and psychosocial dilemmas, which, in order to introduce FA as a scientifically and socially accepted procedure into clinical practice, need to be discussed, answered and solved. Methods:, This review is based on a detailed literature research in all relevant databases (MEDLINE, PubMed, Cochrane Library, specialist textbooks), however, recent papers (published between 2006 and 2008) were given highest priority for inclusion. Results:, In this review, two main limitations associated with facial tissue allotransplantation, that is, shortage of donations and life-long need for immunosuppressive treatment, are discussed and presented in both psychosocial and medical terms. Conclusion:, Although both of these limitations potentially could successfully inhibit the transformation of FA from an experimental therapy to the treatment of choice for patients with severe functional facial impairment, recent literature suggest that FA will find a meaningful place in facial reconstructive surgery. [source] | |||||||||||||