In silico evaluation of the thermal stress induced by MRI switched gradient fields in patients with metallic hip implant

This work focuses on the in silico evaluation of the energy deposed by MRI switched gradient fields in bulk metallic implants and the consequent temperature increase in the surrounding tissues. An original computational strategy, based on the subdivision of the gradient coil switching sequences into sub-signals and on the time-harmonic electromagnetic field solution, allows to realistically simulate the evolution of the phenomena produced by the gradient coils fed according to any MRI sequence. Then, Pennes' bioheat equation is solved through a Douglas-Gunn time split scheme to compute the time-dependent temperature increase. The procedure is validated by comparison with laboratory results, using a component of a realistic hip implant embedded within a phantom, obtaining an agreement on the temperature increase better than 5%, lower than the overall measurement uncertainty. The heating generated inside the body of a patient with a unilateral hip implant when undergoing an Echo-Planar Imaging (EPI) MRI sequence is evaluated and the role of the parameters affecting the thermal results (body position, coil performing the frequency encoding, effects of thermoregulation) is discussed. The results show that the gradient coils can generate local increases of temperature up to some kelvin when acting without radiofrequency excitation. Hence, their contribution in general should not be disregarded when evaluating patients' safety

Structural characterization of phytotoxic terpenoids from Cestrum parqui.

Isolation, chemical characterization and phytotoxicity of nine polyhydroxylated terpenes (five C13 nor-isoprenoids, two sesquiterpenes, a spirostane and a pseudosapogenin) from Cestrum parqui LHerr are reported. In this work we completed the phytochemical investigation of the terpenic fraction of the plant and described the structural elucidation of polar isoprenoids using NMR methods. All the configurations of the compounds have been assigned by NOESY experiments. Four new structures have been identified as (3S,5R,6R,7E,9R)-5,6,9-trihydroxy-3-isopropyloxy-7-megastigmene, 5a-spirostan-3b,12b,15a-triol, and 26-O-(30-isopentanoyl)-b-Dglucopyranosyl- 5a-furost-20(22)-ene-3b,26-diol, and as an unusual tricyclic sesquiterpene. The compounds have been assayed for their phytotoxicity on lettuce at the concentrations ranging between 104 and 107 M. The activities of some compounds were similar to that of the herbicide pendimethalin

Italian Wikipedia and epilepsy: an infodemiological study of online information-seeking behavior

Wikipedia is the most commonly accessed source of health information by both healthcare professionals and the lay public worldwide. We aimed to evaluate information-seeking behavior of Internet users searching the Italian Wikipedia for articles related to epilepsy and its treatment. Using Pageviews Analysis, we assessed the total and mean monthly views of articles from the Italian Wikipedia devoted to epilepsy, epileptic syndromes, seizure type, and antiepileptic drugs (AEDs) from January 1, 2015 to October 31, 2017. We compared the views of the article on epilepsy with those of articles focusing on Alzheimer's disease, migraine, multiple sclerosis, syncope, and stroke and adjusted all results for crude disease prevalence. With the only exception of the article on multiple sclerosis, the adjusted views for the Italian Wikipedia article on epilepsy were higher than those for the other neurological disorders. The most viewed articles on seizure type were devoted to tonic-clonic seizure, typical absence seizure, tonic convulsive seizures, and clonic convulsive seizures. The most frequently accessed articles on epilepsy syndromes were about temporal lobe epilepsy and Lennox-Gastaut syndrome. The most frequently viewed articles on AEDs were devoted to valproic acid, carbamazepine, and levetiracetam. Wikipedia searches seem to mirror patients' fears and worries about epilepsy more than its actual epidemiology. The ultimate reasons for searching online remain unknown. Epileptologists and epilepsy scientific societies should make greater efforts to work jointly with Wikipedia to convey more accurate and up-to-date information about epilepsy

Optic nerve sheath diameter ultrasound evaluation in intensive care unit. possible role and clinical aspects in neurological critical patients' daily monitoring

Background. The increase of the optic nerve sheath diameter (ONSD) is a reliable, noninvasive sonographic marker of intracranial hypertension. Aim of the study was to demonstrate the efficacy of ONSD evaluation, when monitoring neurocritical patients, to early identify malignant intracranial hypertension in patients with brain death (BD). Methods. Data from ultrasound ONSD evaluation have been retrospectively analyzed in 21 sedated critical patients with neurological diseases who, during their clinical course, developed BD. 31 nonneurological controls were used for standard ONSD reference. Results. Patients with neurological diseases, before BD, showed higher ONSD values than control group (CTRL: RT  cm; LT  cm; pre-BD: RT  cm; LT  cm; ) even without intracranial hypertension, evaluated with invasive monitoring. ONSD was further significantly markedly increased in respect to the pre-BD evaluation in neurocritical patients after BD, with mean values above 0.7 cm (RT  cm; LT  cm; ), with a corresponding dramatic raise in intracranial pressure. Logistic regression analysis showed a strong correlation between ONSD and ICP ( 0,895, ). Conclusions. ONSD is a reliable marker of intracranial hypertension, easy to be performed with a minimal training. Routine ONSD daily monitoring could be of help in Intensive Care Units when invasive intracranial pressure monitoring is not available, to early recognize intracranial hypertension and to suspect BD in neurocritical patients

The Peach RGF/GLV Signaling Peptide pCTG134 Is Involved in a Regulatory Circuit That Sustains Auxin and Ethylene Actions

In vascular plants the cell-to-cell interactions coordinating morphogenetic and physiological processes are mediated, among others, by the action of hormones, among which also short mobile peptides were recognized to have roles as signals. Such peptide hormones (PHs) are involved in defense responses, shoot and root growth, meristem homeostasis, organ abscission, nutrient signaling, hormone crosstalk and other developmental processes and act as both short and long distant ligands. In this work, the function of CTG134, a peach gene encoding a ROOT GROWTH FACTOR/GOLVEN-like PH expressed in mesocarp at the onset of ripening, was investigated for its role in mediating an auxin-ethylene crosstalk. In peach fruit, where an auxin-ethylene crosstalk mechanism is necessary to support climacteric ethylene synthesis, CTG134 expression peaked before that of ACS1 and was induced by auxin and 1-methylcyclopropene (1-MCP) treatments, whereas it was minimally affected by ethylene. In addition, the promoter of CTG134 fused with the GUS reporter highlighted activity in plant parts in which the auxin-ethylene interplay is known to occur. Arabidopsis and tobacco plants overexpressing CTG134 showed abnormal root hair growth, similar to wild-type plants treated with a synthetic form of the sulfated peptide. Moreover, in tobacco, lateral root emergence and capsule size were also affected. In Arabidopsis overexpressing lines, molecular surveys demonstrated an impaired hormonal crosstalk, resulting in a re-modulated expression of a set of genes involved in both ethylene and auxin synthesis, transport and perception. These data support the role of pCTG134 as a mediator in an auxin-ethylene regulatory circuit and open the possibility to exploit this class of ligands for the rational design of new and environmental friendly agrochemicals able to cope with a rapidly changing environment

Neurological, psychological, and cognitive disorders in patients with chronic kidney disease on conservative and replacement therapy

Chronic kidney disease (CKD) is a highly prevalent condition in the world. Neurological, psychological, and cognitive disorders, related to CKD, could contribute to the morbidity, mortality, and poor quality of life of these patients. The aim of this study was to assess the neurological, psychological, and cognitive imbalance in patients with CKD on conservative and replacement therapy. Seventy-four clinically stable patients affected by CKD on conservative therapy, replacement therapy (hemodialysis (HD), peritoneal dialysis (PD)), or with kidney transplantation (KT) and 25 healthy controls (HC), matched for age and sex were enrolled. Clinical, laboratory, and instrumental examinations, as renal function, inflammation and mineral metabolism indexes, electroencephalogram (EEG), psychological (MMPI-2, Sat P), and cognitive tests (neuropsychological tests, NPZ5) were carried out. The results showed a significant differences in the absolute and relative power of delta band and relative power of theta band of EEG (P=0.008, P<0.001, P=0.051), a positive correlation between relative power of delta band and C-reactive protein (CRP) (P< 0.001) and a negative correlation between estimated glomerular filtration rate (eGFR) (P<0.001) and 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) (P<0.001), in all the samples. Qualitative analysis of EEG showed alterations of Grade 2 (according to Parsons-Smith classification) in patients on conservative therapy, and Grade 2-3 in KT patients. The scales of MMPI-2 hysteria and paranoia, are significantly correlated with creatinine, eGFR, serum nitrogen, CRP, 1,25-(OH)2D3, intact parathyroid hormone (iPTH), phosphorus, and cynical and hysterical personality, are correlated with higher relative power of delta (P=0.016) and theta band (P= 0.016). Moreover, all NPZ5 scores showed a significant difference between the means of nephropathic patients and the means of the HC, and a positive correlation with eGFR, serum nitrogen, CRP, iPTH, and vitamin D. In CKD patients, simple and noninvasive instruments, as EEG, and cognitive-psychological tests, should be performed and careful and constant monitoring of renal risk factors, probably involved in neuropsychological complications (inflammation, disorders of mineral metabolism, electrolyte disorders, etc.), should be carried out. Early identification and adequate therapy of neuropsychological, and cognitive disorders, might enable a better quality of life and a major compliance with a probable reduction in the healthcare costs

How to Process Sputum Samples and Extract Bacterial DNA for Microbiota Analysis

Different steps and conditions for DNA extraction for microbiota analysis in sputum have been reported in the literature. We aimed at testing both dithiothreitol (DTT) and enzymatic treatments of sputum samples and identifying the most suitable DNA extraction technique for the microbiota analysis of sputum. Sputum treatments with and without DTT were compared in terms of their median levels and the coefficient of variation between replicates of both DNA extraction yield and real-time PCR for the 16S rRNA gene. Treatments with and without lysozyme and lysostaphin were compared in terms of their median levels of real-time PCR for S. aureus. Two enzyme-based and three beads-based techniques for DNA extraction were compared in terms of their DNA extraction yield, real-time PCR for the 16S rRNA gene and microbiota analysis. DTT treatment decreased the coefficient of variation between replicates of both DNA extraction yield and real-time PCR. Lysostaphin (either 0.18 or 0.36 mg/mL) and lysozyme treatments increased S. aureus detection. One enzyme-based kit offered the highest DNA yield and 16S rRNA gene real-time PCR with no significant differences in terms of alpha-diversity indexes. A condition using both DTT and lysostaphin/lysozyme treatments along with an enzymatic kit seems to be preferred for the microbiota analysis of sputum samples

Electromagnetic phenomena in heterogeneous media: Effective properties and local behavior

The purpose of this paper is the use of a mathematical homogenization approach based on the multiple scale expansion theory for modeling the electromagnetic phenomena arising in heterogeneous media under an imposed magnetic flux. The attention is focused on the analysis and discussion of the merits and limits of this theoretical approach in reproducing not only the effective macroscopic properties but also the local behavior, under a wide frequency range and considering different constitutive and geometrical parameters. The results show that the proposed method is able to predict local and integral physical quantities, ranging from a substantially global behavior in the whole media to significantly localized effects determined by the microscopic structure

Airway microbiome and host inflammatory response in bronchiectasis

Non-cystic fibrosis bronchiectasis (hereby referred to as bronchiectasis) is a chronic respiratory disease characterized by irreversible dilation of bronchi in the context of chronic syndrome mainly represented by daily cough, sputum production and frequent pulmonary exacerbations. Bronchiectasis pathophysiology is recognised in the development of a vicious circle of infection, inflammation, mucous clearance and pulmonary damage. Although microbial community and inflammation have a very important role in respiratory diseases, few is known in bronchiectasis. The aim of this PhD project was to evaluate sputum microbiome and its interaction with the local host inflammatory response in adults with bronchiectasis during their stable state. Several studies were conducted to explore this research question. In the second chapter, we report the methodological selection of techniques for both microbiome and active neutrophil elastase (aNE) analysis in sputum. The third chapter is divided into three different sections. In the first, we identified two groups of adult bronchiectasis patients with different microbiome diversity levels. The low microbiome diversity group was found to be enriched in Pseudomonas, Staphylococcus and Streptococcus. Multivariate analysis identified FEV1%predict.<50, radiology and primary ciliary dyskinesia (PCD) to be independently associated with low microbiome diversity. The following section represents a preliminary study focused on bronchiectasis aetiologies, more specifically PCD and immunodeficiency. The study concerning PCD did not identify a clear association between aetiology, microbiome and inflammation comparing a group of matched PCD with idiopathic or post infective bronchiectasis, although, a trend could be observed.Subsequently, immunodeficiency was comparedto idiopathic bronchiectasis. These two groupsidentified, primary immunodeficiency and idiopathic differed in terms of alpha diversity and quantification of H. influenzae which was higher in the immunodeficiency group. Chapter fourfocuses on neutrophilic inflammation looking at the association of aNE in bronchiectasis with microbiome analysis. We found evidences of low microbiome diversity and P. aeruginosa identification in patients with high levels of aNE. The following study focused on active Cathepsin G (Cat-G) which is a putative biomarker for bronchiectasis. Cat-G was associated with disease severity, radiological severity, quality of life and chronic infection. It was also associated with low microbiome diversity and P. aeruginosa molecular detection. Finally, Cat-G and aNE resulted to be similar in predicting bronchiectasis severity (bronchiectasis severity index -BSI), severe exacerbation and chronic infection in bronchiectasis patients during stable state. Finally, in chapter five, we analyse microbiome and inflammation among adult bronchiectasis patients with chronic P. aeruginosa infection. Association network analysis identified differences in terms of number of interactions of Pseudomonas with other genera and interactions between cytokines and microbial effectors in patients with different exacerbations/year. We hope that this thesis may be a step forward in better understanding the role of both microbiome and inflammation in bronchiectasis that may lead to unravelling of endotypes and the identification of therapeutic targets. This will finally result in advances in a precise medicine approach for bronchiectasis patients