177 research outputs found
The multicenter European Biological Variation Study (EuBIVAS): a new glance provided by the Principal Component Analysis (PCA), a machine learning unsupervised algorithms, based on the basic metabolic panel linked measurands
Abstract
Objectives
The European Biological Variation Study (EuBIVAS), which includes 91 healthy volunteers from five European countries, estimated high-quality biological variation (BV) data for several measurands. Previous EuBIVAS papers reported no significant differences among laboratories/population; however, they were focused on specific set of measurands, without a comprehensive general look. The aim of this paper is to evaluate the homogeneity of EuBIVAS data considering multivariate information applying the Principal Component Analysis (PCA), a machine learning unsupervised algorithm.
Methods
The EuBIVAS data for 13 basic metabolic panel linked measurands (glucose, albumin, total protein, electrolytes, urea, total bilirubin, creatinine, phosphatase alkaline, aminotransferases), age, sex, menopause, body mass index (BMI), country, alcohol, smoking habits, and physical activity, have been used to generate three databases developed using the traditional univariate and the multivariate Elliptic Envelope approaches to detect outliers, and different missing-value imputations. Two matrix of data for each database, reporting both mean values, and "within-person BV" (CVP) values for any measurand/subject, were analyzed using PCA.
Results
A clear clustering between males and females mean values has been identified, where the menopausal females are closer to the males. Data interpretations for the three databases are similar. No significant differences for both mean and CVPs values, for countries, alcohol, smoking habits, BMI and physical activity, have been found.
Conclusions
The absence of meaningful differences among countries confirms the EuBIVAS sample homogeneity and that the obtained data are widely applicable to deliver APS. Our data suggest that the use of PCA and the multivariate approach may be used to detect outliers, although further studies are required
Preliminary Study of the Effects of Pulsed Electric Field (PEF) Treatments in Wines Obtained from Early-Harvested Sangiovese Grapes.
In this experiment, the effect of pulsed electric field (PEF) technology on the extractability
of anthocyanins and polyphenols in early-harvested Sangiovese red grapes (16.9\ub0Bx sugar, 3.26 pH,
and 10.4 g/L titratable acidity) from Emilia Romagna (Italy) was investigated. Electric field strengths
were in the range of 0.9\u20133 kV/cm, generated by the application of short, high-voltage pulses, and the
grapes were subjected to specific energies from 10.4 to 32.5 kJ/kg immediately after crushing and
destemming to produce a pre-fermentative pulsed electric field treatment on a pilot scale. Grape
musts and wines were analyzed for color components and polyphenols content from pressing of juices
up to 3 months from the end of the fermentation of wines. Furthermore, the freshly-fermented wines
were subjected to accelerated aging conditions (i.e., warming under 40\ub0C for 32 days) to simulate the
evolution of color parameters with time. The color intensity was generally higher in treated musts
and wines compared to the control, further increased by raising the intensity of the electric field.
Results suggested the potentialities of pulsed electric fields (PEFs) as a mild pre-fermentative process
to assist maceration and to increase the polyphenolic content of musts obtained by early-harvested
Sangiovese grapes
A novel mutation in SACS gene in a family from southern Italy
A form of autosomal recessive spastic ataxia (ARSACS) has been described in the
Charlevoix and Saguenay regions of Quebec. So far a frameshift and a nonsense
mutation have been identified in the SACS gene. The authors report a new mutation
(1859insC), leading to a frameshift with a premature termination of the gene
product sacsin, in two sisters from consanguineous parents. The phenotype is
similar to previously described patients with ARSACS
Twenty-four or Four-and-twenty : Language Modulates Cross-Modal Matching for Multi-Digit Numbers in Children and Adults
Does number–word structure have a long-lasting impact on transcoding? Contrary to English, German number words comprise decade–unit inversion (e.g., vierundzwanzig is literally translated as four-and-twenty). To investigate the mental representation of numbers, we tested the effect of visual and linguistic–morphological characteristics on the development of verbal–visual transcoding. In a longitudinal cross-linguistic design, response times (RTs) in a number-matching experiment were analyzed in Grade 2 (119 German-speaking and 179 English-speaking children) and in Grade 3 (131 German-speaking and 160 English-speaking children). To test for long-term effects, the same experiment was given to 38 German-speaking and 42 English-speaking adults. Participants needed to decide whether a spoken number matched a subsequent visual Arabic number. Systematic variation of digits in the nonmatching distractors allowed comparison of three different transcoding accounts (lexicalization, visual, and linguistic–morphological). German speakers were generally slower in rejecting inverted number distractors than English speakers. Across age groups, German speakers were more distracted by Arabic numbers that included the correct unit digit, whereas English speakers showed stronger distraction when the correct decade digit was included. These RT patterns reflect differences in number–word morphology. The individual cost of rejecting an inverted distractor (inversion effect) predicted arithmetic skills in German-speaking second-graders only. The moderate relationship between the efficiency to identify a matching number and arithmetic performance could be observed cross-linguistically in all age groups but was not significant in German-speaking adults. Thus, findings provide consistent evidence of a persistent impact of number–word structure on number processing, whereas the relationship with arithmetic performance was particularly pronounced in young children
European Biological Variation Study (EuBIVAS): Within- and between-subject biological variation estimates for serum thyroid biomarkers based on weekly samplings from 91 healthy participants
Objectives: Thyroid biomarkers are fundamental for the diagnosis of thyroid disorders and for the monitoring and treatment of patients with these diseases. The knowledge of biological variation (BV) is important to define analytical performance specifications (APS) and reference change values (RCV). The aim of this study was to deliver BV estimates for thyroid stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), thyroglobulin (TG), and calcitonin (CT).
Methods: Analyses were performed on serum samples obtained from the European Biological Variation Study population (91 healthy individuals from six European laboratories; 21–69 years) on the Roche Cobas e801 at the San Raffaele Hospital (Milan, Italy). All samples from each individual were evaluated in duplicate within a single run. The BV estimates with 95% CIs were obtained by CV-ANOVA, after analysis of variance homogeneity and outliers.
Results: The within-subject (CV I ) BV estimates were for TSH 17.7%, FT3 5.0%, FT4 4.8%, TG 10.3, and CT 13.0%, all significantly lower than those reported in the literature. No significant differences were observed for BV estimates between men and women.
Conclusions: The availability of updated, in the case of CT not previously published, BV estimates for thyroid markers based on the large scale EuBIVAS study allows for refined APS and associated RCV applicable in the diagnosis and management of thyroid and related diseases.publishedVersio
An Exploratory Study of Field Failures
Field failures, that is, failures caused by faults that escape the testing
phase leading to failures in the field, are unavoidable. Improving verification
and validation activities before deployment can identify and timely remove many
but not all faults, and users may still experience a number of annoying
problems while using their software systems. This paper investigates the nature
of field failures, to understand to what extent further improving in-house
verification and validation activities can reduce the number of failures in the
field, and frames the need of new approaches that operate in the field. We
report the results of the analysis of the bug reports of five applications
belonging to three different ecosystems, propose a taxonomy of field failures,
and discuss the reasons why failures belonging to the identified classes cannot
be detected at design time but shall be addressed at runtime. We observe that
many faults (70%) are intrinsically hard to detect at design-time
Molecular epidemiology of Usher syndrome in Italy
Purpose: Usher syndrome is an autosomal recessive disorder characterized by hearing and vision loss. Usher syndrome
is divided into three clinical subclasses (type 1, type 2, and type 3), which differ in terms of the severity and progression
of hearing loss and the presence or absence of vestibular symptoms. Usher syndrome is defined by significant genetic
heterogeneity, with at least 12 distinct loci described and 9 genes identified. This study aims to provide a molecular
epidemiology report of Usher syndrome in Italy.
Methods: Molecular data have been obtained on 75 unrelated Italian patients using the most up-to date technology
available for the screening of Usher syndrome gene mutations, i.e., the genotyping microarray developed by Asper Biotech
(Tartu, Estonia), which simultaneously investigates 612 different marker positions using the well established arrayed
primer extension methodology (APEX).
Results: Using this method, we found that 12% of cases (9 out of 75) harbored homozygous or compound heterozygous
mutations in the gene positions analyzed, whereas 20% (15 out of 75) of the patients were characterized by the presence
of only one mutated allele based on the positions analyzed. One patient was found to be compound heterozygous for
mutations in two different genes and this represents an example of possible digenic inheritance in Usher syndrome. A
total of 66.6% of cases (50 out of 75) were found to be completely negative for the presence of Usher syndrome gene
mutations in the detected positions. Mutations detected by the array were confirmed by direct sequencing.
Conclusions: These findings highlight the efficacy of the APEX-based genotyping approach in the molecular assessment
of Usher patients, suggesting the presence of alleles not yet identified and/or the involvement of additional putative genes
that may account for the pathogenesis of Usher syndrome
Spontaneous In Vivo Chondrogenesis of Bone Marrow-Derived Mesenchymal Progenitor Cells by Blocking Vascular Endothelial Growth Factor Signaling
Chondrogenic differentiation of bone marrow-derived mesenchymal stromal/stem cells (MSCs) can be induced by presenting morphogenetic factors or soluble signals but typically suffers from limited efficiency, reproducibility across primary batches, and maintenance of phenotypic stability. Considering the avascular and hypoxic milieu of articular cartilage, we hypothesized that sole inhibition of angiogenesis can provide physiological cues to direct in vivo differentiation of uncommitted MSCs to stable cartilage formation. Human MSCs were retrovirally transduced to express a decoy soluble vascular endothelial growth factor (VEGF) receptor-2 (sFlk1), which efficiently sequesters endogenous VEGF in vivo, seeded on collagen sponges and immediately implanted ectopically in nude mice. Although naïve cells formed vascularized fibrous tissue, sFlk1-MSCs abolished vascular ingrowth into engineered constructs, which efficiently and reproducibly developed into hyaline cartilage. The generated cartilage was phenotypically stable and showed no sign of hypertrophic evolution up to 12 weeks. In vitro analyses indicated that spontaneous chondrogenic differentiation by blockade of angiogenesis was related to the generation of a hypoxic environment, in turn activating the transforming growth factor-β pathway. These findings suggest that VEGF blockade is a robust strategy to enhance cartilage repair by endogenous or grafted mesenchymal progenitors. This article outlines the general paradigm of controlling the fate of implanted stem/progenitor cells by engineering their ability to establish specific microenvironmental conditions rather than directly providing individual morphogenic cues.; Chondrogenic differentiation of mesenchymal stromal/stem cells (MSCs) is typically targeted by morphogen delivery, which is often associated with limited efficiency, stability, and robustness. This article proposes a strategy to engineer MSCs with the capacity to establish specific microenvironmental conditions, supporting their own targeted differentiation program. Sole blockade of angiogenesis mediated by transduction for sFlk-1, without delivery of additional morphogens, is sufficient for inducing MSC chondrogenic differentiation. The findings represent a relevant step forward in the field because the method allowed reducing interdonor variability in MSC differentiation efficiency and, importantly, onset of a stable, nonhypertrophic chondrocyte phenotype
From COVID-19 Pandemic to Patient Safety: A New "Spring" for Telemedicine or a Boomerang Effect?
During the Covid-19 health emergency, telemedicine was an essential asset through which health systems strengthened their response during the critical phase of the pandemic. According to the post-pandemic economic reform plans of many countries, telemedicine will not be limited to a tool for responding to an emergency condition but it will become a structural resource that will contribute to the reorganization of Healthcare Systems and enable the transfer of part of health care from the hospital to the home-based care. However, scientific evidences have shown that health care delivered through telemedicine can be burdened by numerous ethical and legal issues. Although there is an emerging discussion on patient safety issues related to the use of telemedicine, there is a lack of reseraches specifically designed to investigate patient safety. On the contrary, it would be necessary to determine standards and specific application rules in order to ensure safety. This paper examines the telemedicine-risk profiles and proposes a position statement for clinical risk management to support continuous improvement in the safety of health care delivered through telemedicine
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