Biology subjects

Pipitone, R.

Publications and source records attributed to Pipitone, R..

3 recordsLinked to original sources

bioRxiv2025

INFLAMMATORY ACTIVATION, EPIGENETIC SIGNATURE AND MORPHO-STRUCTURAL ALTERATION IN A COHORT OF PATIENTS WITH CHRONIC HEART FAILURE AND PERMANENT ATRIAL FIBRILLATION: A CROSS-SECTIONAL STUDY.

BackgroundAtrial fibrillation (AF) is a complex disorder involving inflammatory, morpho-structural, and genetic factors. Emerging evidence suggests inflammation plays a pivotal role in AF initiation, maintenance, and outcomes. MethodsWe conducted a cross-sectional case-control study to assess whether, among patients with chronic heart failure (CHF) and permanent AF, serum inflammatory cytokines, metabolic parameters, epigenetic factors, and echocardiographic markers of structural remodeling are interrelated. Eighty-two consecutive CHF patients with permanent AF and 82 CHF patients with sinus rhythm and no AF history were enrolled from the Internal Medicine and Stroke Care Unit at "P. Giaccone" Hospital, Palermo, between January 2020 and May 2022. ResultsAF patients were older and exhibited higher left atrial volume index (LAVI), reduced left atrial (LA) strain, increased relative wall thickness (RWT), and lower ejection fraction (EF%). Renal markers, including estimated glomerular filtration rate (eGFR) and microalbuminuria, were significantly different. Inflammatory markers such as C-reactive protein (CRP), interleukin 6 (IL-6), interleukin 8 (IL-8), and NT-proBNP were elevated in the AF group. Multivariable logistic regression identified LAVI, LA strain, microalbuminuria, albumin/creatinine ratio (ACr), and protein/creatinine ratio (PCr) as independent predictors of AF. Correlation analyses demonstrated strong associations between echocardiographic, inflammatory, and renal parameters. No significant differences in circulating miRNAs were observed. ConclusionsThese findings highlight the intricate interconnection between atrial remodeling, renal dysfunction, and systemic inflammation in AF pathogenesis. A better understanding of these mechanisms may inform future risk stratification strategies and support the development of more effective, targeted therapies in patients with CHF.

scientific communication and education↗

bioRxiv2022

Crosshair, semi-automated targeting for electron microscopy with a motorised ultramicrotome

Volume electron microscopy (EM) is a time consuming process - often requiring weeks or months of continuous acquisition for large samples. In order to compare the ultrastructure of a number of individuals or conditions, acquisition times must therefore be reduced. For resin-embedded samples, one solution is to selectively target smaller regions of interest by trimming with an ultramicrotome. This is a difficult and labour-intensive process, requiring manual positioning of the diamond knife and sample, and much time and training to master. Here, we have developed a semi-automated workflow for targeting with a modified ultramicrotome. We adapted two recent commercial systems to add motors for each rotational axis (and also each translational axis for one system), allowing precise and automated movement. We also developed a user-friendly software to convert X-ray images of resin-embedded samples into angles and cutting depths for the ultramicrotome. This is provided as an open-source Fiji plugin called Crosshair. This workflow is demonstrated by targeting regions of interest in a series of Platynereis dumerilii samples.

cell biology↗

bioRxiv2020

Two distinct phases of chloroplast biogenesis during de-etiolation in Arabidopsis thaliana

Light triggers chloroplast differentiation whereby the etioplast transforms into a photosynthesizing chloroplast and the thylakoid rapidly emerges. However, the sequence of events during chloroplast differentiation remains poorly understood. Using Serial Block Face Scanning Electron Microscopy (SBF-SEM), we generated a series of chloroplast 3D reconstructions during differentiation, revealing chloroplast number and volume and the extent of envelope and thylakoid membrane surfaces. Furthermore, we used quantitative lipid and whole proteome data to complement the (ultra)structural data, providing a time-resolved, multi-dimensional description of chloroplast differentiation. This showed two distinct phases of chloroplast biogenesis: an initial photosynthesis-enabling Structure Establishment Phase followed by a Chloroplast Proliferation Phase during cell expansion. Moreover, these data detail thylakoid membrane expansion during de-etiolation at the seedling level and the relative contribution and differential regulation of proteins and lipids at each developmental stage. Altogether, we establish a roadmap for chloroplast differentiation, a critical process for plant photoautotrophic growth and survival.

plant biology↗