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The Antarctic environment offers a unique opportunity to study the interactions between Porifera and their microbial symbionts. Reports on the association between prokaryotes and Antarctic sponges are increasing. However, a comparison of the bacterial communities associated to the same sponge species but inhabiting different Antarctic areas has seldom been addressed. This study explored the prokaryotes associated with the sponge species Mycale (Oxymycale) acerata (Kirkpatrick, 1907) and Dendrilla antarctica (Topsent, 1905) collected from South Cove at Rothera Point (Antarctic Peninsula) and Thetys Bay (Ross Sea). In D. antarctica , some groups were equally represented at both sites (e.g., Amylibacter , Cutibacterium , Yoonia-Loktanella), whereas members in the genera Polaribacter and Kistimonas were more abundant in Rothera. Similarly, M. acerata individuals collected from Rothera showed a higher relative abundance of some bacterial genera, such as Polaribacter , Sulfitobacter , and Ulvibacter. The results allowed us to identify some taxa common to sponges belonging to the same species and highlighted the possible influence of site-specific environmental conditions in shaping symbionts. • The prokaryotic communities associated with two common Antarctic sponge species is reported. • Mycale acerata and Dendrilla antarctica specimens were collected from two distant Antarctic sectors. • Site-specific environmental conditions prevailed in shaping the sponge-associated prokaryotic communities. • Some distinct microbial features characterized the two sponge species. [ABSTRACT FROM AUTHOR]

Abstract Heavy metals (HMs) and polychlorobiphenyls (PCBs) enter the Arctic environment through a variety of anthropogenic sources with deleterious effects towards biota and public health. Bacteria first transfer toxic compounds to higher trophic levels and, due to the tight link existing between prokaryotic community functions and the type and concentration of contaminants, they may be useful indicator of pollution events and potential toxicity to other forms of life. The occurrence and abundance of HM-tolerant and PCB-oxidizing bacteria in the sub-Arctic Pasvik river area, heavily impacted by anthropogenic modifications, was related to HM and PCB contamination. This latter more likely derived from local inputs rather than a global contamination with higher PCB and HM amounts (and higher bacterial viable counts) that were determined in inner and middle sections of the River. Finally, a panel of bacteria with potential applications in the bioremediation of cold environments were selected and phylogenetically identified. Graphical abstract Unlabelled Image Highlights • The Pasvik River was contaminated by heavy metals and polychlorobiphenyls. • Bacterial heavy metal tolerance was in the order Cu>Zn>Cd>Hg. • Bacterial viable counts were higher in highest contaminated samples. • Bacteria may be used as bioindicators of human impact in Arctic areas. • Bacteria could be exploited in the bioremediation of contaminated cold areas. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The occurrence and distribution of heavy metals (HMs) in sediments was evaluated. • Deep sea microbial communities have the capacity to tolerate HMs. • HM-tolerance of benthic microbial communities was in the order Zn > Cu > Hg > Cd. • HM-tolerant deep sea microbes could be used for the decontamination of marine areas. • HM-tolerant microbes may be used as bioindicators of human impact on the deep sea. Abstract Heavy metals (HMs) enter the marine environment through a variety of sources, especially in areas such as submarine canyons acting as conduits for terrigenous pollutants to the deep sea. HMs exert toxic effects at different levels of biological organization, yet several marine microbes have the capacity to tolerate HMs. However, the relationships between microbes, their tolerance mechanisms and the concentration of HMs in the marine environment are poorly investigated. We evaluated the occurrence and distribution of HMs and culturable HM-resistant microorganisms in sediments collected in two submarine canyons and the adjacent slope in the NE Ligurian margin (Mediterranean Sea), down to 2000 m depth, and explored the role of contaminants in modulating community adaptation to metals. HM concentrations exhibited wide spatial variability across the whole study area, without showing significant differences between canyon and open slope environments, exception made for higher Cd concentrations recorded in one canyon. Benthic microbial abundance was negatively correlated with Cd concentration, while viable counts of HM-resistant microorganisms indicated tolerance of HMs in the order Zn2+ > Cu2+ > Hg2+ > Cd2+. Differences in the tolerance patterns were observed among sampling stations, with microbial communities generally tolerating up to three HMs. Cd2+ was the less tolerated metal, with microbial growth in the presence of this metal observed only for 50 ppm, and only at five of the eleven sampled stations. Our results show the existence of complex multitolerance patterns in deepsea sediments subjected to anthropogenic influence, suggesting that microbial HM tolerance develops under different ways and mechanisms that have to be elicited. Also, they highlight the opportunity for further exploitation of the potential of HM-resistant deep sea microbes for the remediation of contaminated marine areas, or for their use as bioindicators of human impact down to the deep sea. [ABSTRACT FROM AUTHOR]

This study was aimed at gaining insights on the prokaryotic community (in terms of both taxonomic composition and activities) inhabiting the active layer at Edmonson Point, an ice-free area on the eastern slope at the foot of Mount Melbourne (Northern Victoria Land, Antarctica). Samples were collected during the thawing period, when microbial physiological activities are restored to utilize previously frozen organic substrates. Despite the very small cell sizes (<0.1 μm 3 ), indicating the occurrence of stressed, dormant and/or starved cells, the prokaryotic communities appeared to be metabolically active in the decomposition of high molecular weight (>600 Da) substrates, as indicated also by the obtained rates of enzymatic hydrolytic activities over proteolytic, glycolitic and phosphoric compounds. Taxonomical composition showed that Proteobacteria, Actinobacteria and Firmicutes dominated the prokaryotic community, with most of their members playing crucial roles in organic matter turnover, as well as nitrogen cycling, or entering a viable but not cultivable state to cope with continuously changing environmental conditions, such as in the case of the active layer. Finally, non-autochthonous bacteria (mainly of marine origin) were detected and they probably contribute to the organic matter turnover within such cold terrestrial habitat. This research provides the first comprehensive account of the prokaryotic communities inhabiting the Antarctic permafrost and contributes to existing information on the response of their abundance and metabolism in a permafrost area that undergoes to seasonal changes (e.g. in terms of temperature, water availability and ice presence). [ABSTRACT FROM AUTHOR]

Open fjords are subject to contrasting environmental conditions, owing to meltwater glacial inputs, terrestrial runoff, and marine water mass exchanges, which are exacerbated by anthropogenic and climate perturbations. Following a slope-dependent water circulation, the subtidal sandy sediment belt regulates the convergent transport of nutrients downward the fjord depths, and the effective entrapment of suspended particles and microorganisms. In this study, we aimed at testing how glacial and seawater inputs may influence the bacterial community structure of subtidal sand deposits in the Kongsfjorden. Through total and viable cell counting and an amplicon sequencing approach, we found relevant differences in bacterial community structure along the glacio-marine sampling transect. Viable and high nucleic acid content (HNA) cells represented an important fraction of the total community, generally decreasing toward the glacier front. Besides the predominance of Alpha- and Gammaproteobacteria , Bacteroidetes , Firmicutes and Parcubacteria , the bacterial community structure was likely affected by the glacial activity in the inner fjord, with the occurrence of distinctive phylotypes belonging to Gemmatimonadates , Nitrospirae , Acidobacteria , and Chloroflexi . Overall, our outcomes highlighted that exploring the bacterial community distribution and structure can provide new insights into the active role of sand deposits in coastal cold environments. [ABSTRACT FROM AUTHOR]

Fecal calprotectin (FC) is used to asses the presence of intestinal inflammation also in patients with Cystic Fibrosis (CF) and recent studies showed a correlation between bowel and lung disease in these patients. The aim of this study was to analyze the levels of FC in CF and correlate them with different phenotypes of disease. We enrolled a cohort of 54 CF patients and 50 healthy controls. In these patients, calprotectin has been assayed on a stools sample using an ELISA kit. In all patients we analyzed, FC levels were elevated above the cut-off value and significantly higher than in healthy controls. Among CF patients, FC was significantly higher in patients older than 18 years, with pancreatic insufficiency, underweight status, Pseudomonas Aeruginosa airways colonization, CF-related diabetes mellitus, reduced lung function, or high number of pulmonary exacerbations. These results suggest that in patients with CF, FC levels are not only influenced by the CF enteropathy but also by the severity of the genetic disease. Since we found higher FC levels in patients with a severe phenotype ( P. Aeruginosa airways colonization, FEV1 < 50% of predicted, pancreatic insufficiency, underweight status,) we suggest that this marker could be useful to monitor longitudinally a clinical worsening. [ABSTRACT FROM AUTHOR]

Persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), have been detected in abiotic Arctic matrices: surface sediments and seawater from coastal areas in the Kongsfjorden were collected and analyzed. Levels of PCBs varied depending on the sampling site. Total PCB concentrations were between 11.63 (site C2W) and 27.69 pg l − 1 (site AW). These levels were comparable to those reported previously in lake sediments from the northern Svalbard. The occurrence and biodegradation potential of cold-adapted PCB-oxidizing bacteria in seawater and sediment along the fjord was also evaluated. After enrichment with biphenyl, 246 isolates were obtained with 45 of them that were able to grow in the presence of the PCB mixture Aroclor 1242, as the sole carbon source. The catabolic gene bph A was harbored by 17 isolates with affiliates to the genera Algoriphagus , Devosia and Salinibacterium that have been never reported as able to utilize PCBs, thus deserving further investigation. The total removal of Aroclor 1242 and selected PCB congeners was evaluated at 4 and 15 °C for eight bph A-harboring isolates and Gelidibacter sp. DS-10. With few exceptions, tested strains showed greater efficiency at 15 than at 4 °C. Isolates were able to reduce most chromatographic peaks by > 50%, with some di- and trichlorobiphenyls that were quite totally removed (> 90%). [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 (COVID-19) caused more than 52.775.271 million confirmed cases, 1.293.106 deaths, globally, and afflicted 208 countries, areas, or territories; and almost three months have passed since the World Health Organisation (WHO) declared COVID-19 as a pandemic. Despite the dramatic and global impact of the Coronavirus, the knowledge about the SARS-CoV-2 infection has been improved remarkably. Herein, we provided the rationale for SARS-CoV-2 infection as endothelial dysfunction rather than respiratory disease. Accordingly, we strongly invited the researchers to look beyond pulmonary injury and shift their attention from respiratory disease to endothelial disorder. This strategy could be particularly relevant to identifying therapeutic weapons stabilizing the endothelium rather than the lungs. [ABSTRACT FROM AUTHOR]

17-β-estradiol, involved in mesothelioma pathogenesis, and its precursors were explored as potential biomarkers for the early diagnosis of mesothelioma. Using enzyme-linked immunosorbent assay(ELISA) for 17-β-estradiol and ultra-high performance liquid chromatography/tandem mass spectrometry(UHPLC-MS/MS) for 19 17-β-estradiol precursors, a comprehensive analysis of 20steroid hormones was conducted in the serum of mesothelioma patients(n=67), asbestos-exposed healthy subjects(n=39), and non-asbestos-exposed healthy subjects(n=35). Bioinformatics analysis explored three potential serum biomarkers: 17-β-estradiol, DHEA-S, and androstenedione. The results revealed significant differences in 17-β-estradiol levels between mesothelioma patients and both non-asbestos-exposed and asbestos-exposed healthy subjects. No significant variations in serum 17-β-estradiol levels were observed among mesothelioma patients at different stages, suggesting its potential as an early diagnostic marker. 17-β-estradiol levels were similar in mesothelioma patients with environmental and occupational asbestos exposure, while males with occupational asbestos exposure exhibited significantly higher levels of 17-β-estradiol compared to females. Significant reduction in androstenedione and an increase in DHEA-S were observed in asbestos-exposed individuals compared to non-asbestos-exposed individuals. The analysis of DHEA-S-androstenedione-17-β-estradiol signature score showed an increase in asbestos-exposed individuals and mesothelioma patients compared to non-asbestos-exposed individuals, and this score effectively distinguished between the groups. The Cancer Genome Atlas data was utilized to analyze the expression of 5-α-reductase1 and hydroxysteroid-17β-dehydrogenase2 genes. The findings indicated that mesothelioma patients with elevated gene values for 5-α-reductase1 and hydroxysteroid-17β-dehydrogenase2 have a worse or better prognosis on overall survival, respectively. In conclusion, this study suggests 17-β-estradiol, DHEA-S, and androstenedione as biomarkers for mesothelioma risk and early diagnosis of mesothelioma in asbestos-exposed individuals, aiding timely intervention and improved care. [Display omitted] • E2 increased in healthy asbestos-exposed subjects and MPM patients. • DHEA-S-androstenedione-E2 signature score increased in asbestos-exposed subjects. • The signature differentiates subjects exposed to asbestos from those not exposed. • DHEA-S-androstenedione-E2 as biomarkers of MPM risk and early diagnosis of MPM. [ABSTRACT FROM AUTHOR]