Excess Lead-210 and Plutonium-239+240: Two suitable radiogenic soil erosion tracers for mountain grassland sites.

The expected growing population and challenges associated with globalisation will increase local food and feed demands and enhance the pressure on local and regional upland soil resources. In light of these potential future developments it is necessary to define sustainable land use and tolerable soil loss rates with methods applicable and adapted to mountainous areas. Fallout-radionuclides (FRNs) are proven techniques to increase our knowledge about the status and resilience of agro-ecosystems. However, the use of the Caesium-137 (137Cs) method is complicated in the European Alps due to its heterogeneous input and the timing of the Chernobyl fallout, which occurred during a few single rain events on partly snow covered ground. Other radioisotopic techniques have been proposed to overcome these limitations. The objective of this study is to evaluate the suitability of excess Lead-210 (210Pbex) and Plutonium-239+240 (239+240Pu) as soil erosion tracers for three different grassland management types at the steep slopes (slope angles between 35 and 38°) located in the Central Swiss Alps. All three FRNs identified pastures as having the highest mean (± standard deviation) net soil loss of -6.7 ± 1.1, -9.8 ± 6.8 and -7.0 ± 5.2 Mg ha-1 yr-1 for 137Cs, 210Pbex and 239+240Pu, respectively. A mean soil loss of -5.7 ± 1.5, -5.2 ± 1.5 and-5.6 ± 2.1 was assessed for hayfields and the lowest rates were established for pastures with dwarf-shrubs (-5.2 ± 2.5, -4.5 ± 2.5 and -3.3 ± 2.4 Mg ha-1 yr-1 for 137Cs, 210Pbex and 239+240Pu, respectively). These rates, evaluated at sites with an elevated soil erosion risk exceed the respective soil production rates. Among the three FRN methods used, 239+240Pu appears as the most promising tracer in terms of measurement uncertainty and reduced small scale variability (CV of 13%). Despite a higher level of uncertainty, 210Pbex produced comparable results, with a wide range of erosion rates sensitive to changes in grassland management. 210Pbex can then be as well considered as a suitable soil tracer to investigate alpine agroecosystems.

Overview of the impact of Typhoid and Paratyphoid fever. Utility of Ty21a vaccine (Vivotif®).

Cases of diarrhoeal disease number from 1.7 to 5 billion per year worldwide. One of the main causes of diarrhoeal disease is typhoid fever, which is a potentially life-threatening multi-systemic illness. According to the most recent estimates, a total of 26.9 million typhoid fever episodes occurred in 2010. The geographical distribution of the disease differs widely; in developed countries, the incidence rate per 100,000 per year varies from < 0.1 to 0.3, and the disease mainly affects people who travel to endemic areas located in low- and middle-income countries. Low- and middle-income countries are mainly affected owing to the lack of clean water and proper sanitation. In the fight against this plague, prevention is fundamental, and vaccination against typhoid is an effective measure. Vivotif® is an oral live attenuated vaccine which contains a mutated strain of Salmonella (Ty21a) and reproduces the natural infection. The vaccine was first licensed in Europe in 1983 and in the US in 1989, and over the years it has proved efficacious and safe. It is indicated for adults and children from 5 years of age upwards. Specifically, in the most developed countries, vaccination is suggested for highrisk population groups and particularly for international travellers to destinations where the risk of contracting typhoid fever is high. It must also be borne in mind that international travel is increasing. Indeed, international tourist arrivals totalled 1,184 million in 2015 and, on the basis of current trends, international travel is expected to grow by 3-4% in 2017. Vivotif® appears to be a powerful means of disease prevention, the importance of which is highlighted by the spread of antibiotic-resistant strains of Salmonella typhy (S. typhi).

Impact of different scoring algorithms applied to multiple-mark survey items on outcome assessment: an in-field study on health-related knowledge.

INTRODUCTION: Health-related knowledge is often assessed through multiple-choice tests. Among the different types of formats, researchers may opt to use multiple-mark items, i.e. with more than one correct answer. Although multiple-mark items have long been used in the academic setting - sometimes with scant or inconclusive results - little is known about the implementation of this format in research on in-field health education and promotion. METHODS: A study population of secondary school students completed a survey on nutrition-related knowledge, followed by a single- lecture intervention. Answers were scored by means of eight different scoring algorithms and analyzed from the perspective of classical test theory. The same survey was re-administered to a sample of the students in order to evaluate the short-term change in their knowledge. RESULTS: In all, 286 questionnaires were analyzed. Partial scoring algorithms displayed better psychometric characteristics than the dichotomous rule. In particular, the algorithm proposed by Ripkey and the balanced rule showed greater internal consistency and relative efficiency in scoring multiple-mark items. A penalizing algorithm in which the proportion of marked distracters was subtracted from that of marked correct answers was the only one that highlighted a significant difference in performance between natives and immigrants, probably owing to its slightly better discriminatory ability. This algorithm was also associated with the largest effect size in the pre-/post-intervention score change. DISCUSSION: The choice of an appropriate rule for scoring multiple- mark items in research on health education and promotion should consider not only the psychometric properties of single algorithms but also the study aims and outcomes, since scoring rules differ in terms of biasness, reliability, difficulty, sensitivity to guessing and discrimination.

Analysis of influenza vaccination coverage among the elderly in Genoa (Italy) based on a deprivation index, 2009-2013.

INTRODUCTION: The elderly suffer the most influenza-related complications, and 90% of deaths due to influenza occur in older subjects. Consequently, the elderly are among the main targets of influenza vaccination campaigns. The use of deprivation indexes can help to identify subgroups with lower vaccination uptake. This study analyzed influenza vaccination coverage in elderly persons living in Genoa (Italy) in relation to a local Index of Socio-Economic and Health Deprivation (SEHDI) in order to identify population subgroups needing specific intervention to improve vaccination coverage. METHODS: The study targeted subjects aged ≥ 65 years living in Genoa in the period 2009-2013. Information on vaccination coverage was provided by general practitioners and Local Health Units. A combination of linear regression, factor analysis and cluster analysis was used to construct the SEHDI at Census Tract (CT) level, on the basis of data from the 2011 Italian census. RESULTS: In 2011, people aged ≥ 65 years accounted for the 27.7% of the population of Genoa. Most elderly subjects were assigned to either the medium (45.3%) or medium-high (32%) deprivation groups, while the percentages in the extreme tails were low (3.6% high deprivation; 1.3% low deprivation). Significant, non-linear (p < 0.05 NL) relationships were observed in both sexes with regard to mortality due to all respiratory diseases (RD) and chronic obstructive pulmonary disease (COPD), with the highest Standardized Mortality Ratio (SMR) values in women in the high deprivation group of women (1.81, p < 0.05 RD; 1.79, p < 0.05 COPD). The SMRs for influenza and pneumonia showed a positive linear trend in women (p < 0.05) with the highest value in the high deprivation group (1.97, p < 0.05), while in men the trend was NL (p < 0.05). A positive linear trend (p < 0.05) was found with regard to vaccination coverage, which grew weakly as deprivation increased, up to the medium-high deprived group (from 34.6% to 44.4%). However, the high deprivation group showed the lowest value (33.3%). CONCLUSIONS: The results revealed a relationship between deprivation and influenza vaccination coverage in the elderly. This finding should be taken into account in the organization of vaccination campaigns and should prompt differentiated intervention in each local area.

Functional study of T lymphocyte responsiveness in patients with dementia of the Alzheimer type.

The autologous mixed lymphocyte reaction (AMLR) was used to study T lymphocytes in a group of patients with dementia of the Alzheimer type (DAT) in order to confirm the observation that their T cell proliferation in AMLR was greater than in age-matched controls, and to investigate other pathways of T cell activation, searching for correlations between immunologic and clinical findings in DAT. The mean proliferative response in AMLR was increased in patients with DAT. No differences between patients and age-matched controls were detected when other pathways of T cell activation were investigated. The degree of response in the AMLR varied among patients with DAT. This fits with the suggestion that the disorder may be a heterogeneous syndrome.

Assessment of severity of coronary narrowings by quantitative exercise echocardiography and comparison with quantitative arteriography.

To determine the correlation of quantitative assessment of coronary narrowings with left ventricular functional impairment induced by exercise, 57 patients with 1-vessel coronary artery disease and without evidence of collateral flow were studied. A significant relation was observed between minimal cross-sectional area, percent area stenosis, minimal lumen diameter, percent diameter stenosis and the percentage of segmental area change from rest to peak exercise in a vascular distribution territory (r = 0.76, p less than 0.001; r = -0.55, p less than 0.001; r = 0.56, p less than 0.001; r = -0.75, p less than 0.001, respectively). For minimal cross-sectional area, the best cut-off value to separate significantly patients who had a decrease in contractility at peak exercise testing from those who had a normal response was 2 mm2 (p less than 0.001); for percent cross-sectional area stenosis, it was 75% (p less than 0.001); for minimal lumen diameter, it was 0.7 mm (p less than 0.001); and, for percent diameter stenosis, it was 85% (p less than 0.001). High cut-off values for angiographic variables are necessary to separate significantly patients who have a decrease in contractility at peak exercise testing from those who have a normal response. Several patients with mild coronary stenoses may have either normal or abnormal wall motion during exercise. Thus, exercise echocardiography is a useful tool in detecting the presence of fairly severe anatomic narrowing, whereas it is of limited clinical use in the assessment of intermediate coronary atherosclerotic lesions.

Usefulness of the dipyridamole-Doppler test for diagnosis of coronary artery disease.

Two-dimensional and Doppler echocardiographic studies and a hemodynamic investigation were performed during dipyridamole testing in 42 subjects (13 control subjects and 29 patients with coronary artery disease [CAD]), to evaluate the ability of dipyridamole Doppler echocardiography in identifying patients with ischemic left ventricular dysfunction. In the control group, after dipyridamole infusion, Doppler-derived parameters increased significantly from baseline (p less than 0.001). In patients with CAD, peak flow velocity, flow velocity integral and stroke volume failed to increase after dipyridamole infusion (0.89 +/- 0.21 to 0.85 +/- 0.18 m/s, difference not significant; 14 +/- 3 to 12 +/- 4 cm, difference not significant, and 56 +/- 13 to 50 +/- 14 ml/beat, p less than 0.05, respectively). Heart rate, rate pressure product, systemic vascular resistance and mean right atrial pressure had similar variations in the 2 groups. Changes in the 3 Doppler-derived parameters are closely related to the variations of peak positive dP/dt, stroke volume (thermodilution) and left ventricular end-diastolic pressure and are closely related to the coronary angiography jeopardy score and to the appearance of wall motion abnormalities. Thus, by combining Doppler and 2-dimensional echocardiography, dipyridamole-induced myocardial ischemia may be detected in a high percentage of CAD patients, providing a sensitive tool for identifying patients with high-risk coronary artery anatomy.

A simple method to detect intrathecal production of specific antimeasles antibodies in cerebrospinal fluid during subacute sclerosing panencephalitis.

The intrathecal production of antimeasles antibodies was studied using the enzyme-linked immunosorbent assay in eight specimens of serum and cerebrospinal fluid (CSF) from patients with clinical signs of subacute sclerosing panencephalitis (SSPE). The test was performed using a 1:5 dilution of CSF and a 1:2000 dilution of serum (ratio 1:400) in order to nullify the physiological gradient of immunoglobulins across the blood brain barrier (BBB). This procedure allowed a rapid and accurate assessment of the synthesis of specific immunoglobulins in the CSF and a good evaluation of the permeability of the BBB. A diagnosis of SSPE was provided in five out of eight patients with clinical signs of the disease. Clinical follow-up confirmed the diagnosis of SSPE in the group of patients with clear evidence of intrathecal synthesis of antimeasles antibodies.

Cerebrospinal fluid (CSF) findings in amyotrophic lateral sclerosis.

The cerebrospinal fluid (CSF) was examined in 90 amyotrophic lateral sclerosis (ALS) patients and in 50 age-matched normal controls. Total protein concentration was significantly higher in ALS patients than in normal controls. CSF IgG and albumin, quantitatively determined by single radial immunodiffusion, were significantly increased in ALS. No difference in serum concentrations was observed between ALS patients and normal controls. On isoelectric focusing a clearcut "fingerprint" pattern was observed in 11 of 12 cases. These findings support the hypothesis that blood-brain barrier damage occurs in ALS. The finding of a higher mononuclear cell count in young ALS patients is briefly discussed in the light of the hypothesis that an exogenous agent might be of some relevance in pathogenesis. An alteration of at least one of the CSF parameters considered was found in 45.5% of ALS cases.

The integrity of the blood-brain barrier in Alzheimer's type and multi-infarct dementia evaluated by the study of albumin and IgG in serum and cerebrospinal fluid.

Albumin and IgG have been determined in the serum and cerebrospinal fluid (CSF) of 64 patients affected by Alzheimer's disease and senile dementia of Alzheimer type (SDAT/AD), 17 multi-infarct dementia (MID) patients and 52 controls. The concentrations of albumin and IgG in the serum and CSF have been taken into account to evaluate the integrity of the blood-brain barrier (BBB) and the occurrence of intrathecal immunological activation in demented patients. Clear-cut signs of BBB damage have been shown only in the group of patients affected by MID, whilst none of the two groups of patients displayed signs of immunological activation, expressed by an increase in IgG index, nor abnormally low CSF/serum ratios for IgG, previously suggested as expressive of a "consumption" of IgG by the brain parenchyma.

Cerebrospinal fluid and neuropathological study in Devic's syndrome. Evidence of intrathecal immune activation.

Cerebrospinal fluid (CSF) was studied in 2 cases of Devic's syndrome (DS). In one of these cases autopsy was carried out. The main CSF feature in DS is the association of blood-brain barrier damage and intrathecal IgG synthesis. These findings are in keeping with our neuropathological observation of diffuse central nervous system vasculitis and leptomeningitis. As a whole, our CSF and neuropathological findings in DS are consistently different from those in multiple sclerosis.

Iterative Principal Axes Registration method for analysis of MR-PET brain images.

Computerized automatic registration of MR-PET images of the brain is of significant interest for multimodality brain image analysis. In this paper, we discuss the Principal Axes Transformation for registration of three-dimensional MR and PET images. A new brain phantom designed to test MR-PET registration accuracy determines that the Principal Axes Registration method is accurate to within an average of 1.37 mm with a standard deviation of 0.78 mm. Often the PET scans are not complete in the sense that the PET volume does not match the respective MR volume. We have developed an Iterative Principal Axes Registration (IPAR) algorithm for such cases. Partial volumes of PET can be accurately registered to the complete MR volume using the new iterative algorithm. The quantitative and qualitative analyses of MR-PET image registration are presented and discussed. Results show that the new Principal Axes Registration algorithm is accurate and practical in MR-PET correlation studies.

Three-dimensional anatomical model-based segmentation of MR brain images through Principal Axes Registration.

Model-based segmentation and analysis of brain images depends on anatomical knowledge which may be derived from conventional atlases. Classical anatomical atlases are based on the rigid spatial distribution provided by a single cadaver. Their use to segment internal anatomical brain structures in a high-resolution MR brain image does not provide any knowledge about the subject variability, and therefore they are not very efficient in analysis. We present a method to develop three-dimensional computerized composite models of brain structures to build a computerized anatomical atlas. The composite models are developed using the real MR brain images of human subjects which are registered through the Principal Axes Transformation. The composite models provide probabilistic spatial distributions, which represent the variability of brain structures and can be easily updated for additional subjects. We demonstrate the use of such a composite model of ventricular structure to help segmentation of the ventricles and Cerebrospinal Fluid (CSF) of MR brain images. In this paper, a composite model of ventricles using a set of 22 human subjects is developed and used in a model-based segmentation of ventricles, sulci, and white matter lesions. To illustrate the clinical usefulness, automatic volumetric measurements on ventricular size and cortical atrophy for an additional eight alcoholics and 10 normal subjects were made. The volumetric quantitative results indicated regional brain atrophy in chronic alcoholics.

Knowledge-based 3D analysis from 2D medical images.

An anatomical knowledge-based system for image analysis that interprets CT/MR (computed tomography/magnetic resonance) images of the human chest cavity is reported. The approach utilizes a low-level image analysis system with the ability to analyze the data in bottom-up (or data-driven) and top-down (or model-driven) modes to improve the high-level recognition process. Several image segmentation algorithms, including K-means clustering, pyramid-based region extraction, and rule-based merging, are used for obtaining the segmented regions. To obtain a reasonable number of well-segmented regions that have a good correlation with the anatomy, a priori knowledge in the form of masks is used to guide the segmentation process. Segmentation of the brain is also considered.

Polymorphisms in genes involved in folate metabolism as risk factors for NTDs.

Moderate hyperhomocysteinemia in pregnant women has been associated with an increased risk of neural tube defects (NTDs). Periconceptional supplementation with multi-vitamins containing folic acid may normalize homocysteine metabolism and decrease the NTD risk. The C677 T variant of the MTHFR gene coding for a thermolabile enzyme has been described as the first genetic risk factor that accounts for a group of NTDs characterized by low maternal folate status and high homocysteine concentrations. Another common mutation of the same MTHFR gene, A1298 C, has also been described as an NTD risk factor. In addition to abnormal folate metabolism, anything that compromises the internalization of folate into the cell may be involved in the pathogenesis of NTDs. For this reason, a common polymorphism in the RFC-1 gene encoding the reduced folate carrier protein (A80 G) could also be an additional NTD risk factor. In the present study we examined the genotypic distributions and the allele frequencies of MTHFR A1298 C and RFC-1 A80 G polymorphisms in DNA samples from healthy Italian individuals and compared them to the frequencies observed in NTD cases and their parents. By means of restriction enzymatic analysis, we determined that the frequency of the mutated C allele of the A1298 C mutation was 0.25 among control individuals, which is in the range of that recently reported in other ethnic groups. However, we report that the mutant C allele frequencies are significantly higher among NTD cases and case mothers than among controls (0.39, 0.44, 0.25). Furthermore, for the RFC-1 A80 G mutation, we found that the frequency of the G allele of the RFC-1 mutation was 0.46 in the control population, suggesting that this is a common polymorphism in the Italian population. In spite of the high prevalence of the 80 G/G genotype among healthy subjects, we observed an increased frequency of the G allele in NTD-affected children, and their mothers and fathers. These preliminary results indicate that both the MTHFR and RFC-1 polymorphisms may play a role in NTD risk, at least in the Italian population. Further studies should be directed toward the evaluation of the level of risk conferred by the mutant MTHFR and RFC-1 genotypes, as well as the interaction between these genetic determinants and other nutritional and environmental factors.

Segmentation of medical images through competitive learning.

In image analysis applications, segmentation of gray-level images into meaningful regions is an important low-level processing step. Various approaches to segmentation investigated in the literature, in general, use either local information of gray-level values of pixels (region growing based methods, for example) or the global information (histogram thresholding based methods, for example). Application of these approaches for segmenting medical images often does not provide satisfactory results. Medical images are usually characterized by low local contrast and noisy or faded features causing unacceptable performance of local information based segmentation methods. In addition, because of a large amount of structural information found in medical images, global information based segmentation methods yield inadequate results in region extraction. We present a novel approach to image segmentation that combines local contrast as well as global gray-level distribution information. The presented method adaptively learns useful features and regions through the use of a normalized contrast function as a measure of local information and a competitive learning based method to update region segmentation incorporating global information about the gray-level distribution of the image. In this paper, we present the framework of such a self organizing feature map, and show the results on simulated as well as real medical images.

[Effect of changes of the left ventricular diastolic pressure on the coronary circulation hemodynamics]. / Ruolo delle modificazioni della pressione telediastolica ventricolare sinistra sull'emodinamica del circolo coronarico.

In order to understand the effect of LVEDP changes caused by contrast injection during angiography on coronary hemodynamics we studied 15 patients (5 congestive CMP, 5 mixed angina and 5 controls). Our results do not cope with an important negative role played from LVEDP changes on coronary hemodynamics and cardiac metabolism. Actually LVEDP increase after ventriculography was balanced by coronary flow increase and impedance reduction even when the latter has been matched with LVEDP. We also observed lactate metabolism changes which are not likely to be provoked by myocardial ischemia, since there was not a definite negativization of % lactate extraction and delta A-VO2 always turned to reduction; this is apparently not in agreement with other Authors who had reported metabolic alterations suggestive for myocardial ischemia, even if they did not calculate delta A-VO2 and coronary flow. This difference could be related to the different populations studied, specially when considering the different functional meaning of coronary stenoses of the same degree at angiography. Is thus the Authors' thought that, when coronary reserve is still adequate, is it possible not to take into account LVEDP, which becomes important in patients with a more advanced coronary disease as in those cases this extravascular impedance factor to coronary flow could take his own worsening role.