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The sequencing of the full transcriptome (RNA-seq) has become the preferred choice for the measurement of genome-wide gene expression. Despite its widespread use, challenges remain in RNA-seq data analysis. One often-overlooked aspect is normalization. Despite the fact that a variety of factors or 'batch effects' can contribute unwanted variation to the data, commonly used RNA-seq normalization methods only correct for sequencing depth. The study of gene expression is particularly problematic when it is influenced simultaneously by a variety of biological factors in addition to the one of interest. Using examples from experimental neuroscience, we show that batch effects can dominate the signal of interest; and that the choice of normalization method affects the power and reproducibility of the results. While commonly used global normalization methods are not able to adequately normalize the data, more recently developed RNA-seq normalization can. We focus on one particular method, RUVSeq and show that it is able to increase power and biological insight of the results. Finally, we provide a tutorial outlining the implementation of RUVSeq normalization that is applicable to a broad range of studies as well as meta-analysis of publicly available data., (© The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.)

The shear viscosity in the dilute regime of a model for confined granular matter is studied by simulations and kinetic theory. The model consists on projecting into two dimensions the motion of vibrofluidized granular matter in shallow boxes by modifying the collision rule: besides the restitution coefficient that accounts for the energy dissipation, there is a separation velocity that is added in each collision in the normal direction. The two mechanisms balance on average, producing stationary homogeneous states. Molecular dynamics simulations show that in the steady state the distribution function departs from a Maxwellian, with cumulants that remain small in the whole range of inelasticities. The shear viscosity normalized with stationary temperature presents a clear dependence with the inelasticity, taking smaller values compared to the elastic case. A Boltzmann-like equation is built and analyzed using linear response theory. It is found that the predictions show an excellent agreement with the simulations when the correct stationary distribution is used but a Maxwellian approximation fails in predicting the inelasticity dependence of the viscosity. These results confirm that transport coefficients depend strongly on the mechanisms that drive them to stationary states.

Background: Human bitter taste receptors are encoded by a gene family consisting of 25 functional TAS2R loci. In addition, humans carry 11 TAS2R pseudogenes, some of which display evidence for substantial diversification among species, showing lineage-specific loss of function. Since bitter taste is thought to help prevent the intake of toxic substances, diversity at TAS2R genes could reflect the action of natural selection on the ability to recognize some bitter compounds rather than others. Whether species-specific variation in TAS2R pseudogenes is solely the result of genetic drift or whether it may have been influenced by selection due to different feeding behaviors has been an open question., Results: In this study, we analyzed patterns of variation at human TAS2R pseudogenes in both African and non-African populations, and compared them to those observable in nonhuman primates and archaic human species. Our results showed a similar worldwide distribution of allelic variation for most of the pseudogenes, with the exception of the TAS2R6P and TAS2R18P loci, both of which presented an unexpected higher frequency of derived alleles outside Africa. At the TAS2R6P locus, two SNPs were found in strong linkage disequilibrium (r2 > 0.9) with variants in the functional TAS2R5 gene, which showed signatures of selection. The human TAS2R18P carried a species-specific stop-codon upstream of four polymorphic insertions in the reading frame. SNPs at this locus showed significant positive values in a number of neutrality statistics, and age estimates indicated that they arose after the homo-chimp divergence., Conclusions: The similar distribution of variation of many human bitter receptor pseudogenes among human populations suggests that they arose from the ancestral forms by a unidirectional loss of function. However we explain the higher frequency of TAS2R6P derived alleles outside Africa as the effect of the balancing selection acting on the closely linked TAS2R5 gene. In contrast, TAS2R18P displayed a more complex history, suggesting an acquired function followed by a recent pseudogenization that predated the divergence of human modern and archaic species, which we hypothesize was associated with adaptions to dietary changes.

Normalization of RNA-sequencing (RNA-seq) data has proven essential to ensure accurate inference of expression levels. Here, we show that usual normalization approaches mostly account for sequencing depth and fail to correct for library preparation and other more complex unwanted technical effects. We evaluate the performance of the External RNA Control Consortium (ERCC) spike-in controls and investigate the possibility of using them directly for normalization. We show that the spike-ins are not reliable enough to be used in standard global-scaling or regression-based normalization procedures. We propose a normalization strategy, called remove unwanted variation (RUV), that adjusts for nuisance technical effects by performing factor analysis on suitable sets of control genes (e.g., ERCC spike-ins) or samples (e.g., replicate libraries). Our approach leads to more accurate estimates of expression fold-changes and tests of differential expression compared to state-of-the-art normalization methods. In particular, RUV promises to be valuable for large collaborative projects involving multiple laboratories, technicians, and/or sequencing platforms.

The demand for diet products is continuously increasing, together with that for natural food ingredients. Stevioside and other steviol glycosides extracted from the leaves of the plant Stevia rebaudiana Bertoni are the first natural high-potency sweeteners to be approved for consumption in the United States and the European Union. However, the sweetness of these compounds is generally accompanied by aversive sensations, such as bitter and off-tastes, which may constitute a limit to their consumption. Moreover, consumers' differences in sensitivity to high-potency sweeteners are well known, as well as difficulties in characterizing their aftertaste. Recently, TAS2R4 and TAS2R14 have been identified as the receptors that mediate the bitter off-taste of steviol glycosides in vitro. In the present study, we demonstrate that TAS2R4 gene polymorphism rs2234001 and TAS2R14 gene polymorphism rs3741843 are functional for stevioside bitterness perception.

Olfactory sensory neurons express just one out of a possible ∼ 1,000 odorant receptor genes, reflecting an exquisite mode of gene regulation. In one model, once an odorant receptor is chosen for expression, other receptor genes are suppressed by a negative feedback mechanism, ensuring a stable functional identity of the sensory neuron for the lifetime of the cell. The signal transduction mechanism subserving odorant receptor gene silencing remains obscure, however. Here, we demonstrate in the zebrafish that odorant receptor gene silencing is dependent on receptor activity. Moreover, we show that signaling through G protein βγ subunits is both necessary and sufficient to suppress the expression of odorant receptor genes and likely acts through histone methylation to maintain the silenced odorant receptor genes in transcriptionally inactive heterochromatin. These results link receptor activity with the epigenetic mechanisms responsible for ensuring the expression of one odorant receptor per olfactory sensory neuron., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Confined granular fluids, placed in a shallow box that is vibrated vertically, can achieve homogeneous stationary states due to energy injection mechanisms that take place throughout the system. These states can be stable even at high densities and inelasticities allowing for a detailed analysis of the hydrodynamic modes that govern the dynamics of granular fluids. By analyzing the decay of the time correlation functions it is shown that there is a crossover from a quasielastic regime in which energy evolves as a slow mode to an inelastic regime with energy slaved to the other conserved fields. The two regimes have well differentiated transport properties and in the inelastic regime the dynamics can be described by a reduced hydrodynamics with modified longitudinal viscosity and sound speed. The crossover between the two regimes takes place at a wave vector that is proportional to the inelasticity. A two-dimensional granular model, with collisions that mimic the energy transfers that take place in a confined system, is studied by means of microscopic simulations. The results show excellent agreement with the theoretical framework and allow validation of hydrodynamiclike models.

Introduction: Pain complicates hypertrophic post-burn pathologic scars (PPS) METHODS: To investigate the possible neuropathic origin of pain, 13 patients with painful PPS involving at least 1 hand underwent clinical examination, including the Douleur Neuropathique en 4 questions (DN4) questionnaire; median, ulnar, and radial nerve conduction studies (NCS); cold- (CDT) and heat-induced pain threshold evaluation by quantitative sensory testing; and cutaneous silent period (CSP) testing of the abductor pollicis brevis. Controls included 9 patients with non-painful PPS, 52 healthy subjects, and 28 patients with carpal tunnel syndrome (CTS)., Results: All patients with painful PPS had possible neuropathic pain (DN4 score ≥4). NCS signs of CTS were similarly present in PPS subjects with or without pain. Hands with painful PPS had lower CDT and CSP duration, more frequent cold- and heat-pain hypesthesia, and more thermal allodynia than controls., Conclusions: In PPS, possible neuropathic pain is associated with psychophysical and neurophysiological abnormalities suggestive of small-fiber damage., (Copyright © 2011 Wiley Periodicals, Inc.)

Varicella-zoster virus (VZV) meningoencephalomyelitis is a rare but severe neurological complication of VZV reactivation in immunocompromised patients. We report the case of an HIV-infected individual who developed an acute and severe meningoencephalomyelitis accompanied by a disseminated cutaneous eruption due to VZV. The presence of VZV DNA in cerebrospinal fluid was confirmed by polymerase chain reaction (PCR) technique. The patient started undergoing an intravenous acyclovir therapy with a mild recovery of neurological manifestations. Varicella-zoster virus should be included as a cause of acute meningoencephalomyelitis in patients with AIDS. Early diagnosis followed by specific therapy should modify the rapid and fulminant course for this kind of patients.

Objectives: To identify systemically detectable vascular inflammation associated to redox system unbalance, advanced oxidation protein products (AOPP), formed by HClO reaction with proteins, Thiol levels, and their ratio (AOPP/Thiol ratio) were measured in patients with acute coronary syndromes (ACS)., Design and Methods: We evaluated AOPP/Thiol ratio together with CRP and IL-1β in 18 acute myocardial infarction (AMI) and in 16 unstable angina (UA) patients at admission, and in 16 control subjects (CTR); the measurements were repeated at 1 and at 6 months., Results: At admission, AMI and UA patients displayed higher AOPP/Thiol ratio and CRP and IL-1β compared to CTR subjects. A correlation between AOPP/Thiols and IL-1β in AMI was found. At follow-up, in UA only, AOPP/Thiol ratio and IL-1β levels still remained high., Conclusions: The AOPP/Thiol ratio seems to affect the inflammatory process in ACS, and may represent a reliable marker of oxidative unbalance in this setting of patients., (Copyright © 2011 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Background: Strongyloides stercoralis is a nematode parasite, which is endemic in tropical and subtropical regions. Infection usually remains asymptomatic, but in immunocompromised hosts severe and life-threatening manifestations such as hyperinfection syndrome and disseminated disease might occur., Methods: We retrospectively analyzed the epidemiological and clinical characteristics, including HIV co-infection, microbiological findings, and outcome in 30 patients with strongyloidiasis, who attended in the Infectious Diseases F. J. Muñiz Hospital in Buenos Aires from January 2004 to December 2008., Results: The study included 20 men and 10 women with an average age of 33 years. HIV co-infection was present in 21 patients (70%) with a median CD4 T cell count of 50 cells/mm³ (range 7-355) (average 56 cells/mm³). Among HIV negative patients the following comorbidities were detected: tuberculosis (n = 3) and chronic alcoholism, leprosy treated with corticosteroids, immunosuppressive treatment for psoriasis, and diabetes mellitus (each in one patient). Two patients did not have any predisposing diseases or immunosuppressive treatments. Seventeen patients presented with diarrhea and were classified as chronic intestinal strongyloidiasis (57%), asymptomatic infection with peripheral eosinophilia was diagnosed in 7 (23%), and 6 patients (20%) developed hyperinfection syndrome. Seventeen patients (57%) presented peripheral eosinophilia. Diagnosis was achieved by direct visualization of larvae in feces by Baermann technique (n = 20), by multiple stool smears examinations (n = 2), by combination of both (n = 1), by visualization of the filariform larvae in duodenal fluid and stool (n = 1), and in fecal and bronchoalveolar lavage specimens (n = 6). Overall mortality in this series was 20% (6/30). There was no significant correlation between age and mortality. A significant inverse correlation between the survival rate and CD4 T-cell count as well as eosinophilia was observed. There was also a significant correlation between HIV co-infection and mortality. Twenty-two patients responded favorably to treatment with ivermectin.

Background: In the last decades, microarray technology has spread, leading to a dramatic increase of publicly available datasets. The first statistical tools developed were focused on the identification of significant differentially expressed genes. Later, researchers moved toward the systematic integration of gene expression profiles with additional biological information, such as chromosomal location, ontological annotations or sequence features. The analysis of gene expression linked to physical location of genes on chromosomes allows the identification of transcriptionally imbalanced regions, while, Gene Set Analysis focuses on the detection of coordinated changes in transcriptional levels among sets of biologically related genes. In this field, meta-analysis offers the possibility to compare different studies, addressing the same biological question to fully exploit public gene expression datasets., Results: We describe STEPath, a method that starts from gene expression profiles and integrates the analysis of imbalanced region as an a priori step before performing gene set analysis. The application of STEPath in individual studies produced gene set scores weighted by chromosomal activation. As a final step, we propose a way to compare these scores across different studies (meta-analysis) on related biological issues. One complication with meta-analysis is batch effects, which occur because molecular measurements are affected by laboratory conditions, reagent lots and personnel differences. Major problems occur when batch effects are correlated with an outcome of interest and lead to incorrect conclusions. We evaluated the power of combining chromosome mapping and gene set enrichment analysis, performing the analysis on a dataset of leukaemia (example of individual study) and on a dataset of skeletal muscle diseases (meta-analysis approach). In leukaemia, we identified the Hox gene set, a gene set closely related to the pathology that other algorithms of gene set analysis do not identify, while the meta-analysis approach on muscular disease discriminates between related pathologies and correlates similar ones from different studies., Conclusions: STEPath is a new method that integrates gene expression profiles, genomic co-expressed regions and the information about the biological function of genes. The usage of the STEPath-computed gene set scores overcomes batch effects in the meta-analysis approaches allowing the direct comparison of different pathologies and different studies on a gene set activation level.

In a mixture of two species of grains of equal size but different mass, placed in a vertically vibrated shallow box, there is spontaneous segregation. Once the system is at least partly segregated and clusters of the heavy particles have formed, there are sudden peaks of the horizontal kinetic energy of the heavy particles, that is otherwise small. Together with the energy peaks the clusters rapidly expand and the segregation is partially lost. The process repeats once segregation has taken place again, either randomly or with some regularity in time depending on the experimental or numerical parameters. An explanation for these events is provided based on the existence of a fixed point for an isolated particle bouncing with only vertical motion. The horizontal energy peaks occur when the energy stored in the vertical motion is partly transferred into horizontal energy through a chain reaction of collisions between heavy particles., (© 2011 American Physical Society)

Background: Cluster analysis is a crucial tool in several biological and medical studies dealing with microarray data. Such studies pose challenging statistical problems due to dimensionality issues, since the number of variables can be much higher than the number of observations., Results: Here, we present a general framework to deal with the clustering of microarray data, based on a three-step procedure: (i) gene filtering; (ii) dimensionality reduction; (iii) clustering of observations in the reduced space. Via a nonparametric model-based clustering approach we obtain promising results both in simulated and real data., Conclusions: The proposed algorithm is a simple and effective tool for the clustering of microarray data, in an unsupervised setting.

Background: Chronic hepatitis B virus (HBV) infection is one of the most frequent aetiological factors associated with the development of hepatocellular carcinoma (HCC)., Aim: This study evaluated the temporal trend in the aetiological role played by HBV infection alone in patients diagnosed with HCC during the last 20 years in Italy., Methods: Among the 2042 HCC patients included in the Italian Liver Cancer (ITA.LI.CA.) database, 346 had chronic HBV infection alone. We assessed the proportion of HCC patients with HBV infection in four quinquennia (1987-1991, 1992-1996, 1997-2001, 2002-2006) and evaluated their main clinical, virological and oncological characteristics across these periods., Results: Although the absolute number increased, the proportion of HBV-related HCC relatively decreased over time from 26.7% (47/176 patients) in 1987-1991 to 14.7% (127/862 patients) in 2002-2006 (P=0.0005). Patients' demographical, clinical and virological characteristics were similar across the four quinquennia. A greater proportion of patients was diagnosed with non-advanced HCC in more recent years (from 26% in 1987-1991 to 48% in 2002-2006, P=0.025), likely owing to a growing use of semiannual surveillance (from 63% in 1987-1991 to 80% in 2002-2006)., Conclusions: We observed a significant, relative decrease in the role played by chronic HBV infection alone in the determinism of HCC during the last 20 years. In recent years, more patients are diagnosed with non-advanced HCC probably owing to improvements in HCC detection., (© 2010 John Wiley & Sons A/S.)

Motivation: Microarray normalization is a fundamental step in removing systematic bias and noise variability caused by technical and experimental artefacts. Several approaches, suitable for large-scale genome arrays, have been proposed and shown to be effective in the reduction of systematic errors. Most of these methodologies are based on specific assumptions that are reasonable for whole-genome arrays, but possibly unsuitable for small microRNA (miRNA) platforms. In this work, we propose a novel normalization (loessM), and we investigate, through simulated and real datasets, the influence that normalizations for two-colour miRNA arrays have on the identification of differentially expressed genes., Results: We show that normalizations usually applied to large-scale arrays, in several cases, modify the actual structure of miRNA data, leading to large portions of false positives and false negatives. Nevertheless, loessM is able to outperform other techniques in most experimental scenarios. Moreover, when usual assumptions on differential expression distribution are missed, channel effect has a strikingly negative influence on small arrays, bias that cannot be removed by normalizations but rather by an appropriate experimental design. We find that the combination of loessM with eCADS, an experimental design based on biological replicates dye-swap recently proposed for channel-effect reduction, gives better results in most of the experimental conditions in terms of specificity/sensitivity both on simulated and real data., Availability: LoessM R function is freely available at http://gefu.cribi.unipd.it/papers/miRNA-simulation/

Background: Publicly available datasets of microarray gene expression signals represent an unprecedented opportunity for extracting genomic relevant information and validating biological hypotheses. However, the exploitation of this exceptionally rich mine of information is still hampered by the lack of appropriate computational tools, able to overcome the critical issues raised by meta-analysis., Results: This work presents A-MADMAN, an open source web application which allows the retrieval, annotation, organization and meta-analysis of gene expression datasets obtained from Gene Expression Omnibus. A-MADMAN addresses and resolves several open issues in the meta-analysis of gene expression data., Conclusion: A-MADMAN allows i) the batch retrieval from Gene Expression Omnibus and the local organization of raw data files and of any related meta-information, ii) the re-annotation of samples to fix incomplete, or otherwise inadequate, metadata and to create user-defined batches of data, iii) the integrative analysis of data obtained from different Affymetrix platforms through custom chip definition files and meta-normalization. Software and documentation are available on-line at http://compgen.bio.unipd.it/bioinfo/amadman/.

Background: Various normalisation techniques have been developed in the context of microarray analysis to try to correct expression measurements for experimental bias and random fluctuations. Major techniques include: total intensity normalisation; intensity dependent normalisation; and variance stabilising normalisation. The aim of this paper is to discuss the impact of normalisation techniques for two-channel array technology on the process of identification of differentially expressed genes., Results: Through three precise simulation plans, we quantify the impact of normalisations: (a) on the sensitivity and specificity of a specified test statistic for the identification of deregulated genes, (b) on the gene ranking induced by the statistic., Conclusion: Although we found a limited difference of sensitivities and specificities for the test after each normalisation, the study highlights a strong impact in terms of gene ranking agreement, resulting in different levels of agreement between competing normalisations. However, we show that the combination of two normalisations, such as glog and lowess, that handle different aspects of microarray data, is able to outperform other individual techniques.

Using molecular dynamics we study the behavior of a large particle immersed in a bed of smaller ones. The system is bidimensional, consisting of many rough inelastic hard disks of equal size plus a larger one: the intruder. All possible parameters of the system are kept fixed except for two dimensionless parameters determining the frequency and amplitude of the vibrating base. A systematic exploration of this parameter space leads to determining a transition line separating a zone in which the Brazil nut effect is observed and one in which it is not. The results strongly suggest that, in the region of the parameter space in which the study is made, there is a minimum amplitude and a maximum frequency for the Brazil nut effect to take place. These results compare well with isolated results from other authors.

Objective: To describe the clinical characteristics of postburn scars and determine the independent risk factors specific to these patients. While burns may generate widespread and disfiguring scars and have a dramatic influence on patient quality of life, the prevalence of postburn pathologic scarring is not well documented, and the impact of certain risk factors is poorly understood., Methods: A retrospective analysis was conducted of the clinical records of 703 patients (2440 anatomic burn sites) treated at the Turin Burn Outpatient Clinic between January 1994 and May 15, 2006. Prevalence and evolution time of postburn pathologic scarring were analyzed with univariate and multivariate risk factor analysis by sex, age, burn surface and full-thickness area, cause of the burn, wound healing time, type of burn treatment, number of surgical procedures, type of surgery, type of skin graft, and excision and graft timing., Results: Pathologic scarring was diagnosed in 540 patients (77%): 310 had hypertrophic scars (44%); 34, contractures (5%); and 196, hypertrophic-contracted scars (28%). The hypertrophic induction was assessed at a median of 23 days after reepithelialization and lasted 15 months (median). A nomogram, based on the multivariate regression model, showed that female sex, young age, burn sites on the neck and/or upper limbs, multiple surgical procedures, and meshed skin grafts were independent risk factors for postburn pathologic scarring (Dxy 0.30)., Conclusion: The identification of the principal risk factors for postburn pathologic scarring not only would be a valuable aid in early risk stratification but also might help in assessing outcomes adjusted for patient risk.

Background: Rapid and reliable bed-side determination of blood glucose concentration is very important in the management of acutely ill infants and especially in premature newborns. HemoCue is an easy-to-use glucose analyser. The aim of the present study was to examine the usefulness of the HemoCue glucose analyser compared to a reference plasma glucose method (SYS, BM/Hitachi 747/737) in a neonatal intensive care unit (NICU)., Methods: Seventy-eight consecutive neonates admitted to our NICU were enrolled in the study. At the time of the study all patients were grouped according to nutritional management (parenteral or enteral nutrition), haematocrit values and birth weight. The effects of feeding management, haematocrit values, and birth weight on accuracy and precision of the device were evaluated., Results: Overall data linear regression analysis yielded an r-value of 0.905 and the Bland-Altman method demonstrated that HemoCue overestimates plasma glucose by 0.932 mmol/L. Evaluation of our data by receiver operating characteristic curve demonstrated 100% sensitivity cutoff at 4.1 mmol/L., Conclusions: HemoCue cannot be used satisfactorily in the management of glycaemia in the NICU. In the preterm population, birth weight had a dramatic influence on HemoCue accuracy. Low haematocrit and parenteral feeding further contributed to a decrease in the accuracy of this device.

Background & Aims: It has been suggested that clinically relevant portal hypertension may affect the therapeutic management and prognosis of cirrhotic patients with hepatocellular carcinoma (HCC). Nevertheless, the importance of the presence of esophageal varices in these patients has not yet been addressed formally. In this study our aim was to evaluate the prevalence and prognostic relevance of the presence of esophageal varices in a large series of patients with HCC., Methods: The prevalence of esophageal varices was evaluated in 1153 HCC patients who were consecutively referred to 10 Italian centers (the Italian Liver Cancer group). Survival was calculated from the time of HCC diagnosis until death or until the most recent follow-up visit, and was evaluated according to the presence or absence of esophageal varices. The independent prognostic meaning of the presence of esophageal varices was evaluated further in a multivariate regression analysis., Results: Esophageal varices were found in 730 patients (63.3%). Patients with varices showed significantly shorter survival times (P < .0001) as compared with patients without varices. Death as a result of bleeding was more common in patients with varices (P = .0127). In multivariate analysis, the presence of esophageal varices was associated independently with poorer survival (adjusted relative risk, 1.25; 95% confidence interval, 1.06-1.48; P = .0095)., Conclusions: More than half of the patients with HCC have esophageal varices. The presence of esophageal varices is associated with a higher risk of death from bleeding, and is an independent determinant of the patient's prognosis. This variable should be taken into account in the diagnostic and therapeutic work-up of HCC patients.

Background: Identification of the presence of significant fibrosis is an important part of the diagnostic work-up of patients with chronic hepatitis C (CHC)., Aim: To evaluate the performance of the aspartate to alanine aminotransferase ratio (AST/ALT ratio) and platelet count in reducing the number of liver biopsies and diagnosing the presence/absence of significant fibrosis in a large cohort of patients with CHC seen at 2 tertiary referral centers., Methods: Liver biopsies of 409 patients with CHC were evaluated. Staging was carried out by means of the Ishak and METAVIR scores in the Italian and US series, respectively. Prevalence of significant fibrosis was 43%. Receiver operating characteristic curves were used to identify AST/ALT ratio and platelet count cutoffs with the highest accuracy for the diagnosis of significant fibrosis. These cutoffs were used to devise a diagnostic algorithm for reducing the number of liver biopsies and diagnosing/ruling out significant fibrosis., Results: AST/ALT ratios increased and platelet counts decreased as liver fibrosis worsened. Both AST/ALT ratio (c-index=0.747) and platelet count (c-index=0.733) had high accuracy for the diagnosis of significant fibrosis. The use of AST/ALT ratio and platelet count cutoffs in a diagnostic algorithm would have avoided liver biopsy in 68.9% of the patients and would have correctly identified the absence/presence of significant fibrosis in 80.5% of these cases., Conclusions: In clinical practice, the use of simple, reproducible, and inexpensive parameters such as the AST/ALT ratio and platelet count can reduce the need for liver biopsy in a substantial proportion of patients with CHC.

Background/aim: To evaluate the relationship between hyaluronic acid/aminopyrine breath test (HA/ABT) ratio and fibrosis score in chronic hepatitis, and between HA/ABT and clinical staging (child-turcotte-pugh'score, CTP; and model for end stage liver disease, MELD) in cirrhosis, as well as to evaluate the aspartate aminotransferase (AST)/ABT in relation to the HA/ABT., Methods: We studied 48 patients with histologically proven chronic hepatitis C (CHC) and 35 patients with compensated cirrhosis (CIR)., Results: HA/ABT and AST/ABT showed a more significant correlation with the fibrosis score than HA or ABT or AST alone in the 48 CHC patients: r=0.568 (P<0.0001), r=0.610 (P<0.0001), r=0.450 (P=0.0021), r=-0.449 (P=0.0021), and r=0.472(P=0.0012), respectively. Progressive liver damage (fibrosis 1-2 vs fibrosis 3-6 vs cirrhosis) was significantly (P<0.05) reflected by both HA/ABT (mean+/-SEM: 4.0+/-0.9 vs 18.1+/-4.2 vs 149.9+/-33.1) and AST/ABT (6.3+/-1.8 vs 12.7+/-1.6 vs 42.1+/-14.6). A strong relationship was found between HA/ABT and AST/ABT (r=0.755 P<0.0001). In cirrhotic patients, the most significant relationship was observed between HA/ABT and CTP r=0.483 and P=0.0049, and MELD r=0.523 and P=0.0023., Conclusion: Considering that HA levels in chronic hepatitis depend on the progressive impairment of sinusoidal endothelial cells (SEC), related to progressive fibrosis, HA/ABT ratio would seem to be the most specific reflection of progressive impairment of the SEC. AST/ABT could be used as a possible surrogate of HA in identifying SEC impairment in chronic hepatitis.

Substitutive treatment of sepsis associated acute renal failure is an emergent challenge in the intensive care unit due to the number of cases and to the high mortality rate. Standard hemofiltration is unable to improve survival, since a high mortality rate is sustained by the septic process. New therapeutic approaches currently available are based on the increased clearance of molecules ranging 10-30 kDa considered important in the physiopathology of sepsis and multiorgan failure. Clinical experiences in progress are: (1) adsorption resins able to bind bacterial products, cytokines, anaphylotoxins and several inflammation mediators; (2) the bioartificial kidney, that is the addition to hemofilter of human tubular cell culture grown in devices in order to mimic metabolic tubular function to a traditional hemofilter; (3) increased exchange volumes (high volume hemofiltration), up to 0-100 L/24 hr and; (4) increased membrane permeability associated with either discarded ultrafiltrate (high cut-off membranes) or plasma substitution plasmapheresis with regeneration by sorbents technology (C FA). Generally, by applying these new technologies to septic shock patients, the observed survival was higher than that predicted by the gravity score. While these results are encouraging, they are not conclusive and need further study.

Objective: The aim of this study was to assess the diagnostic value and the usefulness of sonohysterography (SHG) in the detection of uterine anomalies, compared with other diagnostic methods., Study Design: From January 2002 to December 2003, we collected 54 patients with a history of primary or secondary infertility or repeated spontaneous abortion and with a clinically or sonographically suspected abnormal uterus. All patients had previously undergone hysterosalpingography (ISG). All patients were examined by standard transvaginal ultrasound. Sonohysterography was then carried out by the intrauterine injection of an isotonic saline solution. Suspected uterine anomalies were also confirmed by hysteroscopy (HS) and/or laparoscopy., Results: Sonohysterography was able to detect all the anomalies. The sensitivity and specificity of sonohysterography were the same as for hysteroscopy. However, there was no significant difference between the diagnostic capabilities of the methods analyzed., Conclusions: Transvaginal sonohysterography with saline solution is a low-cost, easy, and helpful examination method for uterine malformations. We propose that sonohysterography should be performed for the primary investigation of infertility and repeated miscarriages.

Background: The Model for End-Stage Liver Disease (MELD) score is an important and well established tool for assessing prognosis in patients with liver cirrhosis. It has been suggested that the longitudinal evaluation of the MELD score may reflect the progression of liver failure more reliably and therefore be more useful in prognostic assessment., Aim: To assess the prognostic meaning of MELD score modifications in a cohort of cirrhotic patients in whom clinical and biochemical workup was carried out at least twice during a minimum interval of 30 days., Methods: Forty-six cirrhotic patients were longitudinally evaluated for a median follow-up of 365 days. After initial assessment, all the patients had at least one clinical and biochemical reevaluation during follow-up, which was performed no less than 1 month after initial evaluation. MELD was calculated at entry and at second evaluation. DeltaMELD was calculated as MELD at second evaluation minus MELD at entry. DeltaMELD/time was calculated as DeltaMELD divided by time elapsed between initial assessment and second evaluation expressed in months., Results: During follow-up, 13 patients died (28%). The median interval between clinical evaluations was 120 days. MELD scores at entry (13 +/- 4 vs 16 +/- 6, P = 0.0516) and DeltaMELD (0 +/- 4 vs 4 +/- 2, P = 0.0028) were significantly different between patients who died and those who survived during the 1-year follow-up. All the patients who died during follow-up showed an increase of at least 1 unit in DeltaMELD/time (sensitivity = 100%), and all the patients who survived showed a decrease of more than 1 unit in DeltaMELD/time (specificity = 100%)., Conclusions: Longitudinal evaluation of the MELD score provides important prognostic information that seems to complete the prognostic definition provided by "static" MELD. Prospective studies in larger series are needed to validate the prognostic use of MELD modifications over time.

The objective of this study was to demonstrate the differences in the urethrovesical junction angle and urethral mobility by means of perineal ultrasounds in women following vaginal delivery with respect to nulliparous women. We have enrolled 34 women, 12 nulliparous (Group A) and 22 women in the post-partum period (Group B). The ultrasounds were employed to measure the urethrovesical junction angle ("urethro-pelvic" angle) and the urethral mobility. Data obtained show that the urethro-pelvic angle is narrower in Group A (97.3 degrees) with respect to Group B (112.5 degrees). Urethral mobility while coughing was significantly higher in Group B (30.4 degrees) with respect to Group A (-2 degrees). This study demonstrates the difference in the urethral support at rest and during cough in nulliparous versus recently delivered parous women.

The effect of friction in the thermal convection instability of granular fluids is studied by means of molecular dynamics simulations. It is found that the transitions between different convective states (zero, one, and two rolls) are primarily governed by the average energy loss per collisions and not by the friction and restitution coefficients separately, and can be roughly described in terms of a single effective restitution coefficient. The average energy loss per collisions, for a fixed value of the restitution coefficient, shows a maximum for a friction coefficient kappa approximately 0.3. The presence of this maximum manifests itself as a reentrant behavior in the transition lines in parameter space when the value of the friction coefficient is increased beyond 0.3.

Background: To check the hypothesis that the mobility of the urethrovesical junction in the preoperative phase is different in women that will undergo either vaginal, abdominal, or laparoscopic-assisted vaginal hysterectomy., Methods: Eighty-seven consecutive hysterectomies, carried out between January 1999 and December 2001 in our Department, were retrospectively considered. The type of surgical procedure as well as the approach was decided by the surgeon, according to personal experience. Each patient underwent a preoperative transperineal ultrasound, measuring urethral mobility. The ultrasounds were repeated 1 month and 1 year after surgery., Results: In 35 out of 36 women (97.2%) that underwent vaginal hysterectomy and in nine out of 12 (75%) that underwent laparoscopic-assisted vaginal hysterectomy, we detected a high level of urethral mobility in the preoperative phase, compared with nine out of 39 (23.1%) women that underwent transabdominal hysterectomy., Conclusions: The results of our study allow us to confirm our starting hypothesis. Statistical analysis highlights that preoperative data are significantly different for the three types of hysterectomies, both as urethral mobility values (analysis of variance P

Background and Aims: Liver biopsy examination is the gold standard to diagnose the presence of cirrhosis. The aim of this study was to evaluate the accuracy of both 13 C-aminopyrine breath test ( 13 C-ABT) and 13 C-galactose breath test ( 13 C-GBT) in the noninvasive assessment of the presence of cirrhosis in patients with chronic liver disease., Methods: We evaluated 61 patients with chronic liver disease of diverse etiologies (21 compensated cirrhosis). All patients underwent 13 C-GBT and 13 C-ABT, and the results were expressed as a percentage of the administered dose of 13 C recovered per hour (%dose/h) and as the cumulative percentage of administered dose of 13 C recovered over time (%dose cumulative). Results were analyzed according to absence vs presence of cirrhosis., Results: On average, 13 C-GBT %dose/h and %dose cumulative were decreased significantly in patients with compensated cirrhosis, and the same finding was observed for 13 C-ABT results from 30 to 120 minutes. 13 C-GBT %dose/h at 120 minutes had 71.4% sensitivity, 85.0% specificity, and 83.7% accuracy, whereas 13 C-ABT %dose cumulative at 30 minutes had 85.7% sensitivity, 67.5% specificity, and 77.1% accuracy for distinguishing between the 2 subgroups of patients. Combined assessment of 13 C-GBT and 13 C-ABT increased the diagnostic accuracy (80% positive predictive value) of either test alone and reached 92.5% specificity and 100% sensitivity for the diagnosis of cirrhosis., Conclusions: In patients with chronic liver disease, both 13 C-GBT and 13 C-ABT are useful for the diagnosis of cirrhosis. Combination of the tests increases the diagnostic yield of each test alone.

Purpose: The aim of the present work was to ascertain, through the administration of a psychosocial questionnaire, the difficulties that subjects with defective colour vision experience in carrying out everyday tasks and work, including driving a car with a driver's licence held for no more than 3 years., Methods: Subjects with defective colour vision (n = 151) and subjects with normal vision (n = 302) completed a psychosocial questionnaire regarding the difficulties associated with congenital colour vision deficiency in daily life, work and driving a car. Subjects were diagnosed as colour-blind using the Ishihara test., Results: Statistically significant differences between the two samples were found for daily life activities. Subjects with defective colour vision preferred daytime driving. At night, subjects with defective colour vision had difficulty identifying reflectors on the road and the rear signal lights of cars ahead of them., Conclusion: Colour-blind Calabrian subjects admitted to experiencing colour-related difficulties with a wide range of occupational tasks and leisure pursuits. In particular, colour-blind Calabrian subjects preferred daytime driving, and fewer drove regularly, compared to orthochromatics, who were indifferent to night or daytime driving.

Background: Epidemiological studies have foreseen an increase in the incidence of hepatocellular carcinoma (HCC) in the near future and it is estimated that this trend will mostly affect hepatitis C virus (HCV) positive cirrhotic patients. Therefore, accuracy of HCC staging is an important clinical issue., Aim: To investigate the prognostic usefulness of a series of newly proposed HCC prognostic systems such as the Cancer of the Liver Italian Program (CLIP) score, the Groupe d'Etude et de Traitement du Carcinome Hépatocellulaire (GRETCH) model and the Barcelona Clinic Liver Cancer (BCLC) staging classification when compared with the usefulness of a known staging system such as the Okuda staging system in a group of anti-HCV positive cirrhotic patients with HCC seen at a single centre., Methods: Okuda stage, CLIP score, GRETCH model and BCLC stages were retrospectively computed in 81 anti-HCV positive cirrhotic patients with HCC. We evaluated and compared the ability of these methods to assess survival prognosis., Results: As of December 2001, 51 patients had died and overall median survival was 18 months. All the staging systems were able to identify various patient subgroups with different survival. The CLIP score, the GRETCH model and the BCLC staging classification were better at characterizing the 1-year prognosis of the patients when compared with the Okuda staging system, whilst the 3-year prognostic evaluation was improved only by using the CLIP score or the BCLC staging classification., Conclusions: The prognostic value and usefulness of the CLIP score, the GRETCH model and the BCLC staging classification was reproduced in a single-centre analysis of anti-HCV positive HCC cirrhotic patients. These scores provided a prognostic assessment of our patients which is superior to what was obtained by the Okuda staging system.

Background and Aims: Cirrhotic patients frequently undergo screening endoscopy for the presence of oesophageal varices (OV). In the future, this social and medical burden will increase due to the greater number of patients with chronic liver disease and their improved survival. In this study, our aims were (1) to identify clinical, biochemical, and ultrasonographic parameters which might non-invasively predict the presence of OV in patients with liver cirrhosis; (2) to evaluate the reproducibility of the obtained results in a different, although related, further group of patients; and (3) to assess the predictiveness of the identified rules in patients with compensated cirrhosis., Methods: In the first part of the study we retrospectively evaluated the presence of OV in 145 cirrhotic patients, and in the second part we evaluated the reproducibility of the study results in a subsequent group of 121 patients. Finally, we evaluated these parameters in a subgroup of 145 patients with compensated disease. All 266 patients underwent a complete biochemical workup, upper digestive endoscopy, and ultrasonographic measurement of spleen bipolar diameter. Platelet count/spleen diameter ratio was calculated for all patients., Results: The prevalence rates of OV were 61% and 58% in the first and second groups of patients, respectively. In the first part of the study, we found that platelet count, spleen diameter, platelet count/spleen diameter ratio, and Child- Pugh class were significantly different among patients with or without OV, although the platelet count/spleen diameter ratio was the only parameter which was independently associated with the presence of OV in a multivariate analysis. A platelet count/spleen diameter ratio cut off value of 909 had 100% negative predictive value for a diagnosis of OV. This result was reproduced in the second group of patients as well as in patients with compensated disease. In a cost-benefit analysis, screening cirrhotic patients according to the "platelet count/spleen diameter ratio strategy" was far more cost effective compared with the "scope all strategy"., Conclusions: The platelet count/spleen diameter ratio is the only parameter which is independently associated with the presence of OV, and its negative predictive value is reproducible. Its use is of value even in the subgroup of patients with compensated disease, and it is also cost effective.

Background: Trans-catheter arterial chemoembolisation (TACE) is the most common palliative treatment for hepatocellular carcinoma (HCC). The therapeutic options depend both on the characteristics of the tumour and on functional staging of the cirrhosis., Aim: To evaluate the effects of TACE on the survival of cirrhotic patients with HCC according to different staging systems [Okuda score, Cancer Liver Italian Program (CLIP) score, Model for End-stage Liver Disease (MELD) score] and in relation to the side-effects of TACE., Methods: Fifty cirrhotic patients, 36 CTP class A and 14 class B, underwent 106 TACE treatments with mitoxantrone. Survival at 12, 24, and 36 months was evaluated., Results: MELD at 12 months and CLIP at 24 months were identified as significant variables associated with survival. Combined cut-offs of CLIP and of MELD identified four subgroups of patients with different survivals, at 12, 24 and 36 months, respectively: CLIP >or= 2 and MELD >or= 10 (63%, 20% and 0%), CLIP < 2 and MELD >or= 10 (73%, 40% and 22%), CLIP >or= 2 and MELD < 10 (73%, 40% and 22%) and CLIP < 2 and MELD < 10 (100%, 63% and 50%). Post-TACE side-effects proved to have no influence on survival., Conclusion: In patients with poor probability of survival (CLIP >or= 2 and MELD >or= 10), TACE must be planned with a great deal of caution, while in patients with possibly good outcomes (CLIP < 2 and MELD < 10), more 'aggressive' therapy should be taken into consideration.

Background: Anti-hepatitis C virus (anti-HCV) patients with chronic liver disease (CLD) frequently show markers of previous hepatitis B virus (HBV) infection. Moreover, they may carry occult HBV infection. These features might influence clinical and biochemical features as well as stage of disease., Aim: To assess the prevalence and clinical associations of previous (positivity for anti-HBs and/or anti-HBc antibodies) and occult HBV infection (positivity for HBV-DNA by nested-PCR) in the serum of anti-HCV-positive, HCV-RNA-positive, HBsAg-negative patients with various degrees of CLD seen at a tertiary referral centre., Patients: A total of 119 patients fulfilled the inclusion criteria (84 chronic hepatitis and 35 liver cirrhosis)., Results: Forty-eight patients (40.3%) showed markers of previous HBV infection. This feature was more frequent (P = 0.02) among cirrhotics (57%) as compared to chronic hepatitis patients (33%). Chronic hepatitis patients positive for markers of previous HBV infection had worse histology as compared to negative ones (grading: 6.4 +/- 2.7 versus 4.6 +/- 3.0, P = 0.004; staging: 1.6 +/- 1.2 versus 1.0 +/- 1.0, P = 0.01). Eight patients were positive for HBV-DNA in serum (6.7%). No difference in the presence of occult HBV infection was seen between various degrees of liver disease (7.1% of chronic hepatitis, 5.7% of cirrhosis) and among patients who were positive (10.4%) or negative (4.2%) for markers of previous HBV infection. No significant biochemical, virological, or histological difference was observed between age, age at infection, duration of infection, marker patterns of previous HBV infection-matched HBV-DNA-positive and negative chronic hepatitis patients., Conclusions: Our findings suggest that previous HBV infection among anti-HCV patients is associated with worse disease stage. In these patients, the prevalence of occult HBV infection is low and there is no difference in distribution among patients with or without markers of previous HBV infection. Furthermore, it does not seem to be associated with disease stage. Lastly, at least among patients with chronic hepatitis, it does not seem to affect the severity of disease.

Background: The aspartate aminotransferase-alanine aminotransferase ratio (AST/ALT ratio) has been used to noninvasively assess the severity of disease in patients with chronic liver disease (CLD). We previously demonstrated that progressive liver functional impairment is associated with an increase in the AST/ALT ratio., Objectives: To evaluate the reproducibility and transportability of the AST/ALT ratio in a large cohort of patients with different degrees of hepatitis C virus (HCV)-related CLD, to confirm the correlation between progressive impairment of liver function and increase in the AST/ALT ratio, to evaluate whether diagnostic accuracy of the ALT/AST ratio can be improved by using it with other biochemical variables, and to assess the 1-year prognostic capability of the AST/ALT ratio in patients with liver cirrhosis., Patients and Methods: We retrospectively evaluated 252 patients with HCV-related CLD. The AST/ALT ratio was correlated with the degree of liver fibrosis in patients with chronic hepatitis and with the Child-Pugh score in patients with cirrhosis. All patients had undergone monoethylglycinexylidide (MEGX) testing to evaluate liver function. We assessed the prognostic ability of the AST/ALT ratio in a subset of 63 cirrhotic patients who were followed up for at least 1 year., Results: The AST/ALT ratio was more frequently 1 or higher in cirrhotic patients (P<.001). There was a significant correlation between MEGX values and the AST/ALT ratio (r(s) = -0.621, P<.001). Multivariate stepwise logistic analysis showed that AST/ALT ratio, platelet count (PLT), MEGX values, and prothrombin activity were independently associated with the presence of cirrhosis. Combined assessment of the AST/ALT ratio and/or PLT obtained 97.0% positive predictive value and 97.9% negative predictive value for the diagnosis of cirrhosis. The AST/ALT ratio had 81.3% sensitivity and 55.3% specificity in identifying cirrhotic patients who died within 1-year of follow-up., Conclusions: The AST/ALT ratio is both reproducible and transportable in patients with HCV-related CLD. The AST/ALT ratio is correlated with both histologic stage and clinical evaluation. Progressive liver functional impairment is reflected by an increase in the AST/ALT ratio. Noninvasive evaluation by means of the combined AST/ALT ratio and PLT assessment misclassifies only a few cirrhotic patients. In cirrhotic patients, the AST/ALT ratio provides medium-term prognostic information that is no different from that provided by established prognostic scores.

Background: Indices for predicting survival are essential for assessing prognosis and assigning priority for liver transplantation in patients with liver cirrhosis. The model for end stage liver disease (MELD) has been proposed as a tool to predict mortality risk in cirrhotic patients. However, this model has not been validated beyond its original setting., Aim: To evaluate the short and medium term survival prognosis of a European series of cirrhotic patients by means of MELD compared with the Child-Pugh score. We also assessed correlations between the MELD scoring system and the degree of impairment of liver function, as evaluated by the monoethylglycinexylidide (MEGX) test., Patients and Methods: We retrospectively evaluated survival of a cohort of 129 cirrhotic patients with a follow up period of at least one year. The Child-Pugh score was calculated and the MELD score was computed according to the original formula for each patient. All patients had undergone a MEGX test. Multivariate analysis was performed on all variables to identify the parameters independently associated with one year and six month survival. MELD values were correlated with both Child-Pugh scores and MEGX test results., Results: Thirty one patients died within the first year of follow up. Child-Pugh and MELD scores, and MEGX serum levels were significantly different among patients who survived and those who died. Serum creatinine, international normalised ratio, and MEGX(60) were independently associated with six month mortality while the same variables and the presence of ascites were associated with one year mortality. MELD scores showed significant correlations with both MEGX values and Child-Pugh scores., Conclusions: In a European series of cirrhotic patients the MELD score is an excellent predictor of both short and medium term survival, and performs at least as well as the Child-Pugh score. An increase in MELD score is associated with a decrease in residual liver function.

Background: Hepatitis C virus infection-related cirrhosis is a major risk factor for the development of hepatocellular carcinoma. Hepatocellular carcinoma in anti-hepatitis C virus positive cirrhotics shows an increasing prevalence with ageing, although it is not clear whether the age of the patients can be considered a critical factor in the overall assessment of severity of disease or in the choice of therapeutic procedures and prognosis., Objective: To evaluate the influence of older age on modality of presentation, therapeutic choices, outcome, and survival in anti-hepatitis C virus patients with hepatocellular carcinoma., Methods: We retrospectively evaluated 75 anti-hepatitis C virus positive cirrhotic patients with hepatocellular carcinoma consecutively referred to our unit. Patients were sub-divided into two sub-groups according to their age (<65 or >or=65 years) at tumor diagnosis. The characteristics of the patients and of hepatocellular carcinoma, therapeutic procedures, and survival were then analyzed., Results: Median age of the patients was 68 years and mean duration of infection was 24 years. Clinical characteristics of older hepatocellular carcinoma patients were no different from those of younger ones. Hepatocellular carcinoma was more frequently of diffuse type in patients aged <65 years. However, therapeutic options were no different between the two sub-groups of patients, and a similar proportion of patients did not undergo therapy in either group. Overall, 1- and 2-year survival rates were 73% and 51%, respectively. After a mean follow-up of 21 months a higher number of patients aged <65 years died (p=0.002). Moreover, Kaplan-Meier curves showed longer survival in patients aged >or=65 years (p=0.002). Lastly, diffuse type of hepatocellular carcinoma and tumor staging were the variables independently associated with worse survival in multivariate regression analysis., Conclusions: Hepatocellular carcinoma appears in older anti-hepatitis C virus positive cirrhotic patients showing long duration of infection. Older age of the patients does not seem to influence therapeutic options, and more importantly does not exclude patients from treatment. Lastly, older patients seem to have better prognosis most likely due to hepatocellular carcinoma characteristics, since hepatocellular carcinoma seems to present with more unfavourable characteristics in younger cirrhotic patients.

Objectives: The AST/ALT ratio has shown good diagnostic accuracy in patients with chronic viral liver disease. However, its prognostic utility has never been tested. Recently, the Model for End-Stage Liver Disease (MELD) has been proposed as a simple and effective tool to predict survival in patients with liver cirrhosis. The aims of this study were to assess the 3-month and 1-yr prognostic ability of the AST/ALT ratio in a series of patients with virus-related liver cirrhosis, and to evaluate the relationship between the AST/ALT ratio and the MELD score and to compare their prognostic ability., Methods: The AST/ALT ratios and MELD scores of 99 patients with liver cirrhosis of viral etiology (73 patients with hepatitis C virus and 26 with hepatitis B virus) who had been followed-up for at least 1 yr were retrospectively calculated and correlated with the patients' 3-month and 1-yr prognosis. Receiver operating characteristic curves were used to determine the AST/ALT ratio and the MELD score cut-offs with the best sensitivity (SS) and specificity (SP) in discriminating between patients who survived and those who died. Univariate survival curves were estimated by the Kaplan-Meier method using the cut-offs identified by means of receiver operating characteristic curves., Results: AST/ALT ratios and MELD scores showed a significant correlation (r(s) = 0.503, p = 0.0001). In all, 8% and 30% of the patients had died after 3 months and 1 yr of follow-up, respectively. AST/ALT ratios and MELD scores were significantly higher among the patients who died during both 3-month and 1-yr follow-up. An AST/ALT ratio cut-off of 1.17 had 87% SS and 52% SP, whereas a MELD cut-off of 9 had 57% SS and 74% SP in discriminating between patients who survived and those who died after I yr. The combined assessment of the AST/ALT ratio and/or MELD score had 90% SS and 78% SP. Survival curves of the patients showed that both parameters clearly discriminated between patients who survived and those who died in the short term (AST/ALT ratio, p = 0.0094; MELD score, p = 0.0089) as well as in the long term (AST/ALT ratio, p < 0.0005; MELD score, p = 0.004)., Conclusions: In patients with virus-related cirrhosis, the AST/ALT ratio has prognostic capability that is not significantly different from that of an established prognostic score such as MELD. Combined assessment of the two parameters increases the medium-term prognostic accuracy.

Objectives: To calculate reference ranges for ductus venosus Doppler measurements obtained transabdominally at 10-14 weeks of gestation., Design: Two hundred and one normal fetuses with a crown-rump length (CRL) ranging from 38 to 88 mm were examined in a cross-sectional study. The pulsatility index for veins (PIV), peak velocity during ventricular systole (S-wave), lowest forward velocity during atrial contraction (A-wave) and time-averaged maximum velocity (TAMXV) were recorded from the ductus venosus. Flow velocity waveforms were also classified as normal or abnormal according to the presence (normal) or absence or reversal (abnormal) of frequencies during atrial contraction., Results: Three of 201 fetuses showed an abnormal flow pattern (1.5%; 95% exact confidence interval, 0.3-4.3%). In the 198 fetuses with a normal flow pattern, the mean PIV ranged from 1.07 at a CRL of 38 mm to 1.00 at a CRL of 88 mm (r = -0.093; P = 0.19). A significant increase in mean blood flow velocity with increasing CRL was noted for the S-wave (27.0 cm/s to 33.6 cm/s; r = 0.17; P = 0.02), the A-wave (5.9 cm/s to 7.8 cm/s; r = 0.14; P = 0.04) and the TAMXV (19.4 cm/s to 25.3 cm/s; r = 0.19; P < 0.01). Crown-rump length-specific reference ranges for each parameter were calculated using the method of scaled absolute residuals., Conclusions: Abnormal ductus venosus flow patterns could be observed in normal fetuses, even if they ocurred with a low prevalence. Reference values for Doppler measurements were established in fetuses with normal patterns of flow.

Background: We addressed the definition of limits of error of %CD4+ and CD4+ counts (AbsCD4+) typical of laboratories of excellence, as well as the grading of laboratories based on the decision to take these limits as boundaries of unacceptable data., Methods: We studied the 99.9% confidence intervals of the means of 24 human immunodeficiency virus (HIV)+ and HIV- blood samples analyzed by 18 laboratories of the Liguria Region Quality Assessment Program (Liguria Region QALI). Regression equations of lower (L1) and upper (L2) confidence limits over the means of data cleared of unusual results were used to interpolate limits of error for mean values in the tested range., Results: L1 and L2 were symmetric around the mean and a single absolute difference (Abs Res) between the limits and the mean was found. Abs Res significantly increased over mean values (P = 0.0005 for %CD4+, P < 0.0001 for AbsCD4+). Limits were compatible with errors shown with blind replicates. Unacceptable results, outside the limits, accounted for 25% and 30% of %CD4+ and for 18% and 35% AbsCD4+ in the Liguria Region QALI and in the Piemonte Region QA Program, respectively. Limits interpolated over the median showed a similar grading. A comparable fraction of unacceptable data was also found with the method used in the U.K. National External Quality Assessment Scheme (NEQAS) immune monitoring scheme., Conclusions: We propose the general use of these regression equations to determine bounds for unacceptable data in proficiency testing and to identify laboratories of excellence., (Published 2002 Wiley-Liss, Inc.)

This paper presents quite general bidimensional gas-dynamic equations--derived from kinetic theory-which include the fourth cumulant kappa(r,t) as a dynamic field. The dynamics describes a low-density system of inelastic hard spheres (disks) with normal restitution coefficient r. Two illustrative examples are given and the role of kappa in them is discussed. Our general gas-dynamic equations would deal with 9 hydrodynamic fields (which corresponds to 14 in three-dimension). These fields are the standard hydrodynamic fields plus the components p(ij) of the traceless part of the pressure tensor, the energy flux vector Q and the fourth cumulant kappa. The present formulation requires no constitutive equations. The two examples are: the well-known homogeneous cooling state and a system, with and without gravity, steadily heated by two parallel walls. In the first case, the dynamics yield a description of the homogeneous cooling state consistent with known results adding extra details mainly about the transient time behavior. The steadily heated system kept in a static state gives rise to quite simple but nontrivial equations. In the case with gravity, it is shown that when kappa is included as a dynamic field, the formalism leads to a non-Fourier law already to first order in dissipation. Setting gravity g=0 a perturbative solution is shown and favorably compared with observations obtained from molecular dynamics (MD). In both cases, with and without gravity, kappa is not homogeneous. An analytic extension suggests a divergent situation for a small negative value of q, which originates in the unavoidable extension of the formalism to exothermic collisions associated with a restitution coefficient larger than one. This divergent behavior is observed in MD.

A sun tan is considered a symbol of well-being in our society, but incorrect methods of sun exposure can create serious problems. We present two cases of severe sun-related burns caused by fig leaf decoction used as home-made tanning lotion. Twenty four-thirty six hours after application and sun exposure, patients developed a phytophotodermatitis characterised by erythema, and blister formation involving all the photoexposed areas (45-70% BSA). Their general conditions became rapidly critical and they were admitted to our Burn Centre. The patients were discharged after 11 and 26 days, respectively. Haemolytic anaemia and retinal haemorrhages presented as systemic complications due to the furocoumarins present in the fig leaf decoction.

Background: Host and viral factors have been suggested as possible causative factors for the presence of liver iron accumulation in chronic hepatitis C. However, there is no agreement regarding the influence of liver iron accumulation on the biochemical and histological severity of chronic hepatitis C. Moreover, data concerning the relationships between both viral load and genotype and liver iron accumulation are scanty., Aims: To evaluate the biochemical, histological and virological assessment of a group of chronic hepatitis C patients without risk factors for iron overload, on the basis of the presence, degree and distribution of liver iron accumulation., Methods: Fifty-three chronic hepatitis C patients (34 men, 19 women; age 44 +/- 11 years) with no risk factors for liver iron accumulation and showing no HFE mutations were chosen from a broader cohort of chronic hepatitis C patients. The presence, degree and distribution of liver iron accumulation were assessed using Deugnier's score. Relationships between the presence of liver iron accumulation and grading and staging were carried out separately. Hepatitis C virus RNA serum levels and viral genotype were compared in patients with or without liver iron accumulation. Alpha glutathione S-transferase serum levels were assessed in all patients., Results: Overall, liver iron accumulation was mild and was present in 19 patients (36%). It was associated with male gender (P = 0.0358), and was reflected by high serum iron levels (P = 0.001) and high ferritin levels (P < 0.0001). Hepatitis C virus RNA levels and genotype were not associated with the presence of liver iron accumulation. In multivariate analysis, ferritin was the only variable significantly associated with liver iron accumulation (P < 0.0001). Grading was higher in patients with liver iron accumulation regardless of the site of iron deposition. Fibrosis was present in all patients with iron overload; these patients were more frequently cirrhotic. Moreover, patients with mesenchymal or mixed deposition had higher staging than patients with hepatocytic or no iron deposition. This feature was reflected by higher alpha-glutathione S-transferase levels., Conclusions: Liver iron accumulation is mild in chronic hepatitis C patients without HFE mutations and is mainly reflected by serum ferritin levels. Viral characteristics do not seem to play a role in iron deposition. Liver iron accumulation is associated with higher grading, advanced fibrosis and cirrhosis. Moreover, higher staging is associated with mesenchymal or mixed iron deposition. In these patients, higher alpha-glutathione S-transferase levels seem to reflect more complex damage.

Maternal dietary fatty acids (FFAs) intake and corresponding human milk composition relationships have been assessed throughout the first month of lactation in 34 lactating women consecutively enrolled. All mothers were on their habitual diet. Food records (95 items) were administered to the mothers, six-times during the first month of lactation (1 day after delivery, 4, 7, 14, 21, and 28 days after colostrum appearance) and referred to maternal dietary intake of the day before. Milk collected on day 1 was considered as colostrum, day 4 and 7 samples as transitional milk, and day 14, 21 and 28 samples as mature milk. Five gas chromatographic analyses were performed on each sample. Statistics were made using Friedman's and Pearson's test. Maternal dietary saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) were significantly related to the corresponding milk pattern in the phase of transitional milk (P<0.01), while total polyunsaturated (PUFAs) content was significantly related only to the mature milk (P<0.01); in this phase about 42% of the variations occurring in PUFAs milk content can be related to variation of maternal PUFAs dietary intake. The results in the present study provide evidence of the relationships between maternal diet and milk composition. The degree of correlation between maternal diet and PUFAs milk content increases throughout milk maturational process and reaches significance only in mature milk. This would imply that advancing lactation, milk PUFAs provision sources gradually shift from adipose tissue catabolism to maternal diet., (Copyright 2001 Harcourt Publishers Ltd.)

Damage to bile ducts in chronic hepatitis C is a characteristic histological lesion. Moreover, the presence of abnormal levels of gammaGT in these patients is also a common finding. Assessing whether the presence of bile duct lesions is indicated by biochemical abnormalities or whether virological characteristics can influence their development may help in the definition of clinical-histological relationships in chronic hepatitis C. In this study we evaluated the relationships among routine biochemical parameters, serum bile acids, and pi-class glutathione S-transferase levels, and the presence of bile duct lesions in 60 patients with chronic hepatitis C. Furthermore, we assessed whether the presence of bile duct lesion might be related to HCV genotype, HCV-RNA serum levels, and positivity for HGV-RNA. We found that gammaGT was the only parameter related to the presence of bile duct lesions. Although a trend towards higher serum bile acids and pi-class glutathione S-transferase levels was observed in patients with bile duct lesions, this trend did not reach statistical significance. Different HCV genotypes and RNA levels, and HGV-RNA positivity did not seem to influence the presence of bile duct damage. In conclusion we found that gammaGT levels point out the presence of bile duct lesions in patients with chronic hepatitis C. Since we observed a different pattern of alteration of gammaGT, serum bile acids, and pi-class glutathione S-transferase, we suggest that these various biochemical alterations reflect a more complex damage to bile duct structures, which is not likely represented by the common assessment of bile duct lesions. Viral factors such as HCV genotype and RNA levels as well as HGV-RNA positivity are probably not the main cause of this histological damage.

Objective: Liver biopsy is mandatory for correctly grading and staging chronic hepatitis activity. Nevertheless, serum markers of fibrogenesis may be useful to help us understand the mechanisms of the fibrogenic process, to follow-up patients, and to establish the efficacy of therapy. In this study, our aim was to identify the relationships between pro-collagen III peptide (PIIIP) serum levels and detailed liver histology in a group of untreated patients with chronic hepatitis C (CHC)., Methods: We studied 147 CHC patients. Correlation analysis of PIIIP serum levels was performed in 109 patients, after having excluded those with alcohol abuse or concomitant hepatitis B virus infection. PIIIP serum levels were assessed using an assay that measures both Col 1-3 peptide (reflecting collagen synthesis) and Col 1 peptide (reflecting collagen degradation). Relationships of serum PIIIP with histology was carried out by evaluating grading and staging separately. Moreover, each component of the necro-inflammatory score was also taken into consideration., Results: PIIIP levels were abnormal in 101 patients (93%). Moreover, PIIIP levels were no different between patients with (12.1 +/- 6.3 ng/ml) or without (13 +/- 5.8 ng/ml) fibrosis. In univariate analysis, no relationship was observed with fibrosis (rs = 0.033, not significant), while PIIIP levels were significantly correlated with lobular necrosis only (rs = 0.295, P = 0.0020). Multivariate analysis confirmed this latter finding (P = 0.0150). Among biochemical parameters, PIIIP showed relationships with aminotransferase (AST, rS = 0.294, P = 0.0022; ALT, rs = 0.236, P = 0.0142) and alkaline phosphatase (rs = 0.146, P = 0.0223)., Conclusions: In patients with CHC, serum PIIIP levels reflect histological parameters strictly related to fibrogenesis. Therefore, PIIIP is a useful tool to evaluate ongoing fibrogenic activity of CHC. A complete histological score is needed in order to understand the relationships between biochemical markers of fibrogenesis and histology.