Translocation pathways for inhaled asbestos fibers

We discuss the translocation of inhaled asbestos fibers based on pulmonary and pleuro-pulmonary interstitial fluid dynamics. Fibers can pass the alveolar barrier and reach the lung interstitium via the paracellular route down a mass water flow due to combined osmotic (active Na+ absorption) and hydraulic (interstitial pressure is subatmospheric) pressure gradient. Fibers can be dragged from the lung interstitium by pulmonary lymph flow (primary translocation) wherefrom they can reach the blood stream and subsequently distribute to the whole body (secondary translocation). Primary translocation across the visceral pleura and towards pulmonary capillaries may also occur if the asbestos-induced lung inflammation increases pulmonary interstitial pressure so as to reverse the trans-mesothelial and trans-endothelial pressure gradients. Secondary translocation to the pleural space may occur via the physiological route of pleural fluid formation across the parietal pleura; fibers accumulation in parietal pleura stomata (black spots) reflects the role of parietal lymphatics in draining pleural fluid. Asbestos fibers are found in all organs of subjects either occupationally exposed or not exposed to asbestos. Fibers concentration correlates with specific conditions of interstitial fluid dynamics, in line with the notion that in all organs microvascular filtration occurs from capillaries to the extravascular spaces. Concentration is high in the kidney (reflecting high perfusion pressure and flow) and in the liver (reflecting high microvascular permeability) while it is relatively low in the brain (due to low permeability of blood-brain barrier). Ultrafine fibers (length < 5 μm, diameter < 0.25 μm) can travel larger distances due to low steric hindrance (in mesothelioma about 90% of fibers are ultrafine). Fibers translocation is a slow process developing over decades of life: it is aided by high biopersistence, by inflammation-induced increase in permeability, by low steric hindrance and by fibers motion pattern at low Reynolds numbers; it is hindered by fibrosis that increases interstitial flow resistances

Late Summer Phytoplankton Blooms in the Changing Polar Environment of the Kongsfjorden (Svalbard, Arctic)

Kongsfjorden (Spitsbergen, Svalbard) is an inlet treated as a model site for studies on the impact of climate change in the Arctic due to its hydrological features. In this research, seven-days monitoring was carried out to evaluate the effects of hydrological variability on phytoplankton biomass and diversity in the late summer period. Temperature, salinity, nutrients, total suspended matter, phytoplankton abundance and biomass were determined for each sample. The thermo-haline properties of the column water seemed to affect phytoplankton communities. Their abundances and biomass were correlated with the amount of the total suspended matter. Moreover, species composition and biomass dramatically changed throughout the study period. Cold-water and Atlantic species were replaced by temperatewarm water dinoflagellates, including harmful species. An increase in phytoplankton biomass as well as the presence of dinoflagellate aggregations, mainly composed of Prorocentrum cf. gracile, were detected. This kind of algal accumulation is a new phenomenon in the Arctic and was probably related to the mobilization of sediment-rich glacial meltwaters. These findings, even if preliminary, suggest the need to study how additional biomass pulses and the increase of harmful species may alter the food web structure and the biogeochemical cycles, leading to major ecosystem changes

Water Masses Variability in Inner Kongsfjorden (Svalbard) During 2010–2020

Kongsfjorden is an Arctic fjord located in the Svalbard archipelago. Its hydrography is influenced by the warm and saline Atlantic Water (AW) in the West Spitsbergen Current and the cold and fresh Polar Water circulating on the shelf. We assess the so-called atlantification of Kongsfjorden in the 2010–2020 decade by inspecting modifications in water properties and water masses variability through moored data and summer CTD surveys. Atlantification in this fjord has emerged as an increasing temperature and salinity, resulting from enhanced advection of Atlantic waters from the West Spitsbergen Current. The water column in inner Kongsfjorden warmed by 0.13°C/yr at 35 m and 0.06°C/yr at 85 m depth from 2010 to 2020, while salinity increased by 0.3 PSU. Depth-averaged temperatures have increased by 0.26°C/yr in the warmest months of the year, whereas they appear relatively stable in the coldest months. Both temperature and salinity present a linear regression change point in January 2017, with latter years featuring decreasing values. Highly diluted AW is found at the beginning of the decade, which give way to more and more pure AW in latter years, culminating in extensive intrusions in 2016 and 2017 determining the warmest and saltiest conditions over the decade in inner Kongsfjorden. Observations in the 2010–2020 decade confirm that Kongsfjorden has transitioned to an Atlantic-type fjord, featuring depleted sea ice conditions and rather regular shallow intrusions of AW in summer and frequently also in winter. Although single intrusions of AW are associated with dynamical events on the shelf, we found that the long-term temperature evolution in the inner Kongsfjord is consistent with the meridional temperature transport of the West Spitsbergen Current. The AW current flowing northward from lower latitudes along the western Svalbard archipelago thus has profoundly driven local conditions in the inner fjord in this decade

A small slug from a tropical greenhouse reveals a new rathouisiid lineage with triaulic tritrematic genitalia (Gastropoda: Systellommatophora)

A small slug found in the tropical greenhouse of the Science Museum (MUSE) of Trento (Italy) turned out to be a species of the little-known systellommatophoran family Rathouisiidae. We undertook detailed comparative anatomical and molecular studies using specimens of the MUSE slug, Rathouisia sinensis, and sequences of other systellommatophoran species deposited in GenBank to conduct a systematic and phylogenetic assessment. Analysis of the genitalia of the MUSE slug and R. sinensis revealed an unusual triaulic tritrematic structure: two separate female ducts – one for egg release (oviduct), the other for intake of allosperm (vagina) – and a separate male duct for autosperm release. Analysis of the nucleotide sequences of several mitochondrial (COI, 16S rDNA) and nuclear (18S rDNA, ITS2 flanked by 5.8S and 28S rDNA fragments, H3) gene fragments supported assignation of the MUSE slug to Rathouisiidae, but also its distinction from the other rathouisiid genera Atopos, Granulilimax, Rathouisia and an undescribed genus from the Ryukyu Islands (Japan). Therefore, we decided to describe the MUSE slug as a new species in a new genus: Barkeriella museensis gen. et sp. nov. The species is certainly an alien introduced into the tropical greenhouse of MUSE, but its origin is unknown and calls for further investigation. © 2022 The Linnean Society of London

Breast cancer and communication: Monocentric experience of a self-assessment questionnaire

Background: The communication of the diagnosis of breast cancer induces to the patient a strong psychological trauma. Radiologists are at the forefront of communicating, either for a biopsy or the probable diagnosis of malignancy. This is a complex task, which requires the knowledge and application of correct “communicative models”, among which the SPIKES protocol rep-resents a fundamental reference. Design and methods: 110 patients, with a history of breast cancer, filled out a questionnaire consisting of six questions: five aimed at defining communication compliance with the SPIKES protocol, the sixth, consisting of six feelings, aimed at the knowledge of the next emotional state. Results: Regarding compliance with various “strategic points” of the SPIKES protocol, questionnaires show that 70% of patients reported no omissions, while the remaining 30% reported omissions relatively to perception (56%), emotions (23%), setting (13%), knowledge (6%) and invitation (2%). The results showed the existence of a correlation between the final emotional state and the correct application of the SPIKES protocol; in fact, patients who reacted with a positive final emotional state-reported greater adherence to the strategic points of the SPIKES protocol. Conclusions: In healthcare, knowing the communicative compliance of a team in giving “bad news” is fundamental, especially in breast cancer. The SPIKES protocol is recognized by the Literature as a fundamental reference able to affect “positively” the emotional state of patients. The proposed questionnaire is a valid tool to identify the weak points of communication and related criticalities, to improve clinical practice

Translocation pathways for inhaled asbestos fibers

We discuss the translocation of inhaled asbestos fibers based on pulmonary and pleuro-pulmonary interstitial fluid dynamics. Fibers can pass the alveolar barrier and reach the lung interstitium via the paracellular route down a mass water flow due to combined osmotic (active Na+ absorption) and hydraulic (interstitial pressure is subatmospheric) pressure gradient. Fibers can be dragged from the lung interstitium by pulmonary lymph flow (primary translocation) wherefrom they can reach the blood stream and subsequently distribute to the whole body (secondary translocation). Primary translocation across the visceral pleura and towards pulmonary capillaries may also occur if the asbestos-induced lung inflammation increases pulmonary interstitial pressure so as to reverse the trans-mesothelial and trans-endothelial pressure gradients. Secondary translocation to the pleural space may occur via the physiological route of pleural fluid formation across the parietal pleura; fibers accumulation in parietal pleura stomata (black spots) reflects the role of parietal lymphatics in draining pleural fluid. Asbestos fibers are found in all organs of subjects either occupationally exposed or not exposed to asbestos. Fibers concentration correlates with specific conditions of interstitial fluid dynamics, in line with the notion that in all organs microvascular filtration occurs from capillaries to the extravascular spaces. Concentration is high in the kidney (reflecting high perfusion pressure and flow) and in the liver (reflecting high microvascular permeability) while it is relatively low in the brain (due to low permeability of blood-brain barrier). Ultrafine fibers (length < 5 μm, diameter < 0.25 μm) can travel larger distances due to low steric hindrance (in mesothelioma about 90% of fibers are ultrafine). Fibers translocation is a slow process developing over decades of life: it is aided by high biopersistence, by inflammation-induced increase in permeability, by low steric hindrance and by fibers motion pattern at low Reynolds numbers; it is hindered by fibrosis that increases interstitial flow resistances

Multi-year particle fluxes in Kongsfjorden, Svalbard

Abstract. High-latitude regions are warming faster than other areas due to reduction of snow cover and sea ice loss and changes in atmospheric and ocean circulation. The combination of these processes, collectively known as polar amplification, provides an extraordinary opportunity to document the ongoing thermal destabilisation of the terrestrial cryosphere and the release of land-derived material into the aquatic environment. This study presents a 6-year time series (2010–2016) of physical parameters and particle fluxes collected by an oceanographic mooring in Kongsfjorden (Spitsbergen, Svalbard). In recent decades, Kongsfjorden has been experiencing rapid loss of sea ice coverage and retreat of local glaciers as a result of the progressive increase in ocean and air temperatures. The overarching goal of this study was to continuously monitor the inner fjord particle sinking and to understand to what extent the temporal evolution of particulate fluxes was linked to the progressive changes in both Atlantic and freshwater input. Our data show high peaks of settling particles during warm seasons, in terms of both organic and inorganic matter. The different sources of suspended particles were described as a mixing of glacier carbonate, glacier siliciclastic and autochthonous marine input. The glacier releasing sediments into the fjord was the predominant source, while the sediment input by rivers was reduced at the mooring site. Our time series showed that the seasonal sunlight exerted first-order control on the particulate fluxes in the inner fjord. The marine fraction peaked when the solar radiation was at a maximum in May–June while the land-derived fluxes exhibited a 1–2-month lag consistent with the maximum air temperature and glacier melting. The inter-annual time-weighted total mass fluxes varied by 2 orders of magnitude over time, with relatively higher values in 2011, 2013, and 2015. Our results suggest that the land-derived input will remarkably increase over time in a warming scenario. Further studies are therefore needed to understand the future response of the Kongsfjorden ecosystem alterations with respect to the enhanced release of glacier-derived material

A generative model of hyperelastic strain energy density functions for multiple tissue brain deformation

PURPOSE: Estimation of brain deformation is crucial during neurosurgery. Whilst mechanical characterisation captures stress-strain relationships of tissue, biomechanical models are limited by experimental conditions. This results in variability reported in the literature. The aim of this work was to demonstrate a generative model of strain energy density functions can estimate the elastic properties of tissue using observed brain deformation. METHODS: For the generative model a Gaussian Process regression learns elastic potentials from 73 manuscripts. We evaluate the use of neo-Hookean, Mooney-Rivlin and 1-term Ogden meta-models to guarantee stability. Single and multiple tissue experiments validate the ability of our generative model to estimate tissue properties on a synthetic brain model and in eight temporal lobe resection cases where deformation is observed between pre- and post-operative images. RESULTS: Estimated parameters on a synthetic model are close to the known reference with a root-mean-square error (RMSE) of 0.1 mm and 0.2 mm between surface nodes for single and multiple tissue experiments. In clinical cases, we were able to recover brain deformation from pre- to post-operative images reducing RMSE of differences from 1.37 to 1.08 mm on the ventricle surface and from 5.89 to 4.84 mm on the resection cavity surface. CONCLUSION: Our generative model can capture uncertainties related to mechanical characterisation of tissue. When fitting samples from elastography and linear studies, all meta-models performed similarly. The Ogden meta-model performed the best on hyperelastic studies. We were able to predict elastic parameters in a reference model on a synthetic phantom. However, deformation observed in clinical cases is only partly explained using our generative model

Safety and efficacy of brain biopsy: Results from a single institution retrospective cohort study

INTRODUCTION: Brain biopsy provides important histopathological diagnostic information for patients with new intracranial lesions. Although a minimally invasive technique, previous studies report an associated morbidity and mortality between 0.6% and 6.8%. We sought to characterise the risk linked to this procedure, and to establish the feasibility of instigating a day-case brain biopsy pathway at our institution. MATERIALS AND METHODS: This single-centre retrospective case series study included neuronavigation guided mini craniotomy and frameless stereotactic brain biopsies carried out between April 2019 and December 2021. Exclusion criteria were interventions performed for non-neoplastic lesions. Demographic data, clinical and radiological presentation, type of biopsy, histology and complications in the post-operative period were recorded. RESULTS: Data from 196 patients with a mean age of 58.7 years (SD+/-14.4 years) was analysed. 79% (n=155) were frameless stereotactic biopsies and 21% (n=41) neuronavigation guided mini craniotomy biopsies. Complications resulting in acute intracerebral haemorrhage and death, or new persistent neurological deficits were observed in 2% of patients (n=4; 2 frameless stereotactic; 2 open). Less severe complications or transient symptoms were noted in 2.5% of cases (n=5). 8 patients had minor haemorrhages in the biopsy tract with no clinical ramifications. Biopsy was non-diagnostic in 2.5% (n=5) of cases. Two cases were subsequently identified as lymphoma. Other reasons included insufficient sampling, necrotic tissue, and target error. DISCUSSION AND CONCLUSION: This study demonstrates that brain biopsy is a procedure with an acceptably low rate of severe complications and mortality, in line with previously published literature. This supports the development of day-case pathway allowing improved patient flow, reducing the risk of iatrogenic complications associated with hospital stay, such as infection and thrombosis