15 research outputs found
Valutare la comprensione lessicale in età prescolare: Un confronto tra la BVL_4-12 e il PPVT-R
No full textl presente lavoro di ricerca mira a valutare l’efficacia della prova di Comprensione Lessicale in Età Prescolare della Batteria per la Valutazione del Linguaggio in Bambini dai 4 ai 12 anni (BVL_4-12; Marini et al., 2015) confrontando la prestazione di un gruppo di bambini a questo test con quella ottenuta somministrando una prova, il Peabody Picture Vocabulary Test – Revised (PPVT-R; Dunn & Dunn, 1981, versione italiana a cura di Stella, Pizzoli & Tressoldi, 2001) per bambini dai 3 ai 12 anni di età, di consolidato uso nella pratica clinica. La differenza più evidente tra i due test risiede nella maggiore rapidità di somministrazione del test della BVL_4-12 e nella sua maggiore semplicità di scoring. Per questo studio sono stati reclutati 20 bambini frequentanti il primo anno della scuola dell’infanzia. Di questi, 15 bambini erano caratterizzati da uno sviluppo tipico del linguaggio, mentre i rimanenti 5 erano sottoposti a trattamento logopedico. I risultati di analisi quantitative e qualitative confermano che i due test forniscono informazioni equivalenti in bambini in età prescolare
MBL2 polymorphisms and the choice of controls for association studies: just another story?
No full textGenerative AI as a support tool for the histopathological diagnosis of Hirschsprung disease
No full textopenBackground: La diagnosi di malattia di Hirschsprung (HD) viene confermata attraverso l'analisi istopatologica delle biopsie rettali. Tuttavia, l'esame manuale dei vetrini istologici è un processo laborioso e soggetto ad errori, il che evidenzia la necessità di utilizzare l'Intelligenza Artificiale (AI) come strumento di supporto decisionale. L'applicazione del Machine Learning (ML) nella patologia digitale è spesso limitata dalla ridotta disponibilità di ampi set di immagini di alta qualità.
Scopo: Questo studio propone un approccio innovativo il cui scopo è la creazione di un dataset ottimizzato di immagini istologiche reali da usare come base per la definizione di un modello generativo di immagini sintetiche analoghe al fine di aumentare il numero di immagini disponibili e migliorare indirettamente le prestazioni diagnostiche dei modelli di ML nella malattia di Hirschsprung.
Materiali e metodi: I campioni fissati in formalina sono stati annotati manualmente evidenziando le cellule gangliari e le strutture nervose. Successivamente, sono state applicate tecniche di preprocessing standard, come lo spatial filtering, la normalizzazione dei colori e la segmentazione, per migliorare la qualità delle immagini e creare le maschere. Successivamente, è stato addestrato un modello generativo basato sulla diffusione denoising con l'obiettivo di sintetizzare immagini contenenti cellule gangliari.
Risultati: Abbiamo visionato, selezionato e digitalizzato 108 slides provenienti da pazienti sottoposti ad intervento tra gennaio 2010 e gennaio 2022. Successivamente queste immagini sono state annotate e segmentate per allenare la Generative AI. Il dataset è stato ampliato, grazie all’augumentation, ed è stato suddiviso in piccole sezioni che corrispondono alle dimensioni di ingresso della rete. La rete generativa ha prodotto immagini inedite contenenti cellule gangliari.
Conclusione: L’integrazione di immagini sintetiche e reali, insieme a un’ottimizzazione del preprocessing e della segmentazione, rappresenta una possibile strategia per migliorare le prestazioni del modello nell’identificazione delle caratteristiche diagnostiche di HD. Questo studio evidenzia il potenziale dell’uso combinato di immagini istologiche sintetiche nel training dei sistemi automatici con l’obiettivo di accelerare l’analisi nella diagnosi di HD e ridurre il carico della valutazione manuale.Background: The diagnosis of Hirschsprung disease (HD) is definitively confirmed through the histopathological analysis of rectal biopsies. However, the manual examination of histological slides is a labor-intensive process prone to errors, highlighting the need to utilize Artificial Intelligence (AI) as a decision- support tool. The application of Machine Learning (ML) in digital pathology is often limited by the scarcity of large datasets of high-quality images.
Aim: This study proposes an innovative approach whose aim is to create an optimized dataset of real histological images to be used as the basis for establishing a generative model of similar synthetic images in order to increase the number of available images and indirectly improve the diagnostic performance of ML models in Hirschsprung's disease.
Materials and Methods: Formalin-fixed samples were manually annotated to highlight ganglion cells and nerve structures. Subsequently, standard preprocessing techniques such as spatial filtering, color normalization, and segmentation were applied to improve image quality and create masks. A denoising diffusion-based generative model was then trained with the objective of synthesizing images containing ganglion cells.
Results: We reviewed, selected, and digitized 108 slides from patients who underwent surgery between January 2010 and January 2022. These images were then annotated and segmented to train the Generative AI. The dataset was expanded through augmentation, which were divided into smaller sections corresponding to the input size of the network. The generative network produced novel images containing ganglion cells.
Conclusion: The integration of synthetic and real images, coupled with optimized preprocessing and segmentation, represents a potential strategy to improve the model's performance in detecting the diagnostic features of HD. This study highlights the potential of using synthetic histological images in training automated systems with the goal of accelerating analysis in HD diagnosis and reducing the burden of manual evaluation
Efficacy of ozonation on microbial counts in used brines for cheesemaking
No full textDue to their prolonged use, cheese brines are progressively enriched with organic substances, which allows microorganisms arising from the curds to achieve high concentrations. In this study, the feasibility of using gaseous ozone to reduce the microbial contamination of used brines was evaluated. The antimicrobial effect of ozone increases with the concentration and treatment time, reducing the total bacterial counts by 4.61logcfumL-1, the microstaphylococci counts by 3.37logcfumL-1 and the yeast counts by 2.70logcfumL-1, in the case of the stronger treatments. The antimicrobial effect of ozone was influenced by the protein content of brines. However, in brines that contain high amounts of protein, the inactivation effect of ozone was still significant. The Weibull model accurately estimated both the inactivation and the concavity exhibited in the survival curves for treatments at a concentration of 0.40mgL-1 of ozone for 240min. © 2015 Elsevier Ltd
Occupational Risk Factors for SARS-CoV-2 Infection in Hospital Health Care Workers: A Prospective Nested Case-Control Study
No full textIntroduction: Health Care Workers (HCWs) are at a particular high risk of SARS-CoV-2 infection due to direct and indirect exposure to COVID-19 patients and Aerosol-Generating Procedures (AGPs). The aim of the study was to assess the risk factors for SARS-CoV-2 infection in HCWs exposed to COVID-19 patients, to evaluate the adherence and effectiveness of Infection Prevention and Control (IPC) measures, to describe the clinical presentation for SARS-CoV-2 infection in HCWs and to determine serological responses in HCWs. Methods: HCWs exposed to COVID-19 patients during the previous 14 days with a confirmed case status were recruited as cases; HCWs exposed to COVID-19 patients during the previous 14 days in the same ward without a suspected/probable/confirmed case status were recruited as controls. Serum samples were collected as soon as possible and after 21–28 days from all participants. Data were collected with a WHO standardized questionnaire as soon as possible and after 21–28 days. Results: All social, occupational and personal variables considered were not associated with an increased risk of SARS-CoV-2 infection. Conclusions: Our study showed a high knowledge of IPC measures and very high PPE use among HCWs
Determination of pentraxin 3 levels in cerebrospinal fluid during central nervous system infections
No full textPentraxin 3 (PTX3) is an acute phase protein; its plasmatic levels significantly rise during severe infections. Data on PTX3 levels in cerebrospinal fluid (CSF) of patients with central nervous system (CNS) infections are lacking. We aimed (a) to assess the diagnostic potential of measuring CSF PTX3 levels in patients with CNS infections and (b) to establish CSF PTX3 cutoffs to distinguish between bacterial and aseptic meningoencephalitis (ROC curve). PTX3 levels were measured in CSF from 19 patients admitted to Trieste Hospital, Italy, with CNS infection. A diagnosis of bacterial infection and aseptic meningoencephalitis was made in 7 (37%) and 12 (63%) patients, respectively. Subjects with bacterial infections showed significantly higher PTX3 levels (13.5 vs 1.27 ng/mL in aseptic meningoencephalitis, p = 0.010). We identified two different CSF PTX3 levels cutoffs. (1) The best cutoff to maximise Youden's J was 9.6 ng/mL with a sensitivity, specificity, positive predictive value and negative predictive value (NPV) of 71.4%, 91.4%, 83.3%, 84.6%, respectively. (2) The cutoff with higher NPV (100%) was 3.6 ng/mL; a diagnosis of bacterial infections was obtained in 0% patients with CSF PTX3 levels < 3.6 ng/mL vs 58% of those with CSF PTX3 levels ≥ 3.6 ng/mL (p = 0.017). CSF PTX3 levels are higher in bacterial meningitis than aseptic meningoencephalitis. A cutoff of 3.6 ng/mL of CSF PTX3 has a high NPV and can be used to exclude bacterial CNS infections
Low sensitivity of rapid tests detecting anti-CoV-2 IgG and IgM in health care workers’ serum for COVID-19 screening
No full textBackground: the sensitivity and specificity of a rapid antibody test were investigated for the screening of healthcare workers. Methods: the serum of 389 health care workers exposed to COVID-19 patients or with symptoms, were analysed. All workers underwent monthly the screening for SARS-CoV-2 with detection of viral RNA in nasopharyngeal swabs by RT-PCR. IgG antibody detection in serum was performed by Chemiluminescence Immunoassay (CLIA) and by the Rapid test (KHB diagnostic kit for SARS CoV-2 IgM/IgG antibody after a median of 7.6 weeks (25°-75° percentiles 6.6-11.5). Results: the rapid test resulted positive in 31/132 (23.5%), 16/135 (11.8%) and 0/122 cases in COVID-19 positive individuals, in those with only SARS-CoV-2 IgG antibodies and in those negative for both tests, respectively. Sensitivity was 17.6% (CI95% 13.2-22.7) and 23.5% (CI95% 16.5-31.6), and specificity was 100% (CI95% 97-100) and 100% (CI95% 97-100) considering Rapid test vs CLIA IgG or Rapid test vs SARS-CoV-2 positive RNA detection, respectively. Conclusion: the KHB Rapid test is not suitable for the
screening of workers with previous COVID-19 infection
Monoamine oxidase A-dependent ROS formation modulates human cardiomyocyte differentiation through AKT and WNT activation
No full textDuring embryonic development, cardiomyocytes undergo differentiation and maturation, processes that are tightly regulated by tissue-specific signaling cascades. Although redox signaling pathways involved in cardiomyogenesis are established, the exact sources responsible for reactive oxygen species (ROS) formation remain elusive. The present study investigates whether ROS produced by the mitochondrial flavoenzyme monoamine oxidase A (MAO-A) play a role in cardiomyocyte differentiation from human induced pluripotent stem cells (hiPSCs). Wild type (WT) and MAO-A knock out (KO) hiPSCs were generated by CRISPR/Cas9 genome editing and subjected to cardiomyocyte differentiation. Mitochondrial ROS levels were lower in MAO-A KO compared to the WT cells throughout the differentiation process. MAO-A KO hiPSC-derived cardiomyocytes (hiPSC-CMs) displayed sarcomere disarray, reduced α- to β-myosin heavy chain ratio, GATA4 upregulation and lower macroautophagy levels. Functionally, genetic ablation of MAO-A negatively affected intracellular Ca(2+) homeostasis in hiPSC-CMs. Mechanistically, MAO-A generated ROS contributed to the activation of AKT signaling that was considerably attenuated in KO cells. In addition, MAO-A ablation caused a reduction in WNT pathway gene expression consistent with its reported stimulation by ROS. As a result of WNT downregulation, expression of MESP1 and NKX2.5 was significantly decreased in MAO-A KO cells. Finally, MAO-A re-expression during differentiation rescued expression levels of cardiac transcription factors, contractile structure, and intracellular Ca(2+) homeostasis. Taken together, these results suggest that MAO-A mediated ROS generation is necessary for the activation of AKT and WNT signaling pathways during cardiac lineage commitment and for the differentiation of fully functional human cardiomyocytes. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00395-023-00977-4
Targeted delivery of photosensitizers: efficacy and selectivity issues revealed by multifunctional ORMOSIL nanovectors in cellular systems
No full textPEGylated and non-PEGylated ORMOSIL nanoparticles prepared by microemulsion condensation of vinyltriethoxy-silane (VTES) were investigated in detail for their micro-structure and ability to deliver photoactive agents. With respect to pure silica nanoparticles, organic modification substantially changes the microstructure and the surface properties. This in turn leads to a modulation of both the photophysical properties of embedded photosensitizers and the interaction of the nanoparticles with biological entities such as serum proteins. The flexibility of the synthetic procedure allows the rapid preparation and screening of multifunctional nanosystems for photodynamic therapy (PDT). Selective targeting of model cancer cells was tested by using folate, an integrin specific RGD peptide and anti-EGFR antibodies. Data suggest the interference of the stealth-conferring layer (PEG) with small targeting agents, but not with bulky antibodies. Moreover, we showed that selective photokilling of tumour cells may be limited even in the case of efficient targeting because of intrinsic transport limitations of active cellular uptake mechanisms or suboptimum localization
