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The contribution of oxic methane production to greenhouse gas emissions from lakes is globally relevant, yet uncertainties remain about the levels up to which methanogenesis can counterbalance methanotrophy by leading to CH4 oversaturation in productive surface waters. Here, we explored the biogeochemical and microbial community variation patterns in a meromictic soda lake, in the East African Rift Valley (Kenya), showing an extraordinarily high concentration of methane in oxic waters (up to 156 µmol L−1). Vertical profiles of dissolved gases and their isotopic signature indicated a biogenic origin of CH4. A bloom of Oxyphotobacteria co-occurred with abundant hydrogenotrophic and acetoclastic methanogens, mostly found within suspended aggregates promoting the interactions between Bacteria, Cyanobacteria, and Archaea. Moreover, aggregate sedimentation appeared critical in connecting the lake compartments through biomass and organic matter transfer. Our findings provide insights into understanding how hydrogeochemical features of a meromictic soda lake, the origin of carbon sources, and the microbial community profiles, could promote methane oversaturation and production up to exceptionally high rates., Fazi et al. report on an extraordinarily high biogenic methane concentration detected in the surface water of Lake Sonachi, Kenya. Using gas chromatography and microbiome profiling, they determine that these high concentrations are associated with cyanobacterial blooms and help provide insight to methanogenesis in meromictic soda lakes.

Head and neck cancer (HNC) has frequently an aggressive course for the development of resistance to standard chemotherapy. Thus, the use of innovative therapeutic drugs is being assessed. Bortezomib is a proteasome inhibitor with strong in vitro and in vivo anticancer effects. In vitro antitumoral activity of Bortezomib was investigated employing human pharynx (FaDu), tongue (SCC-15, CAL-27), salivary gland (A-253) cancer cell lines and a murine cell line (SALTO-5) originated from a salivary gland adenocarcinoma arising in BALB-neuT male mice transgenic for the oncogene neu. Bortezomib in vivo effects in BALB-neuT mice transplanted with murine SALTO-5 cells were also examined. Bortezomib inhibited cells proliferation, triggered apoptosis, modulated the expression and activation of pro-survival signal transduction pathways proteins activated by ErbB receptors and inhibited proteasome activity in vitro. Furthermore, intraperitoneal administration of Bortezomib delayed tumor growth of SALTO-5 cells transplanted in BALB-neuT mice and protracted mice survival. Our findings further support the use of Bortezomib for the treatment of HNC and reveal its ineffectiveness in counteracting the activation of deregulated specific signaling pathways in HNC cell lines when resistance to proteasome inhibition is developed.

Il progetto di ricerca ANT-Biolm riguardava lo studio dei processi di colonizzazione microbica in ambienti bentonici della Baia Terra Nova (Mare di Ross), attraverso l'analisi del biolm microbico (batteri, microalghe) e dell'insediamento macrobentonico su substrati articiali, nell'intento di determinarne possibili variazioni causate da disturbi naturali o antropogenici (variazioni di salinità o presenza di contaminanti). I biolms microbici, che giocano un ruolo chiave come substrato per l'insediamento larvale di molte specie di invertebrati, costituiscono hot-spots di diversità microbica; è inoltre noto che le comunità microbiche sono capaci di rispondere rapidamente a mutevoli condizioni ambientali, agendo come potenziali \sentinelle" di perturbazioni naturali o antropiche che negli ultimi anni stanno minacciando il biota che popola gli ecosistemi antartici. Il report raccoglie i risultati salienti delle attività scientifiche condotte nel corso del progetto (dati chimico-fisici acquisiti sulla colonna d'acqua , misure di abbondanza, struttura e metabolismo della comunità microbica associata ai substrati artificiali, abbondanze e tassonomia delle comunità fitoplanctonica e fitobentonica, profili di antibiotico-suscettibilità sui ceppi batterici isolati e delle loro attività enzimatiche, caratterizzazione degli invertebrati bentonici del biofouling)

Bioindication has become an indispensable part of water quality monitoring in most countries of the world, with the presence and abundance of bioindicator taxa, mostly multicellular eukaryotes, used for biotic indices. In contrast, microbes (bacteria, archaea and protists) are seldom used as bioindicators in routine assessments, although they have been recognized for their importance in environmental processes. Recently, the use of molecular methods has revealed unexpected diversity within known functional groups and novel metabolic pathways that are particularly important in energy and nutrient cycling. In various habitats, microbial communities respond to eutrophication, metals, and natural or anthropogenic organic pollutants through changes in diversity and function. In this review, we evaluated the common trends in these changes, documenting that they have value as bioindicators and can be used not only for monitoring but also for improving our understanding of the major processes in lotic and lentic environments. Current knowledge provides a solid foundation for exploiting microbial taxa, community structures and diversity, as well as functional genes, in novel monitoring programs. These microbial community measures can also be combined into biotic indices, improving the resolution of individual bioindicators. Here, we assess particular molecular approaches complemented by advanced bioinformatic analysis, as these are the most promising with respect to detailed bioindication value. We conclude that microbial community dynamics are a missing link important for our understanding of rapid changes in the structure and function of aquatic ecosystems, and should be addressed in the future environmental monitoring of freshwater ecosystems.

Little is known about the quantity and quality of dissolved organic matter (DOM) in waters from continental geothermal systems, with only a few reports available from the Yellowstone US National Park. In this study, we explored the chemodiversity of DOM in water samples collected from two geothermal hot springs from the Kenyan East African Rift Valley, a region extremely rich in fumaroles, geysers, and spouting springs, located in close proximity to volcanic lakes. The DOM characterization included in-depth assessments performed by negative electrospray ionization Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). Reduced, saturated and little aromatic DOM compounds were dominant in the hot spring waters collected from either the Ol Njorowa gorge (ON) or the south shore of the soda-saline Lake Elementaita (ELM). Oxygen-poor and sulfur-bearing DOM molecules prevailed in ON, probably reflecting abiotic sulfurization from sulfide-rich geofluids. Nitrogen-bearing aliphatic and protein-like molecules were abundant in ELM, possibly perfusing through the organic-rich sediments of the adjacent Lake Elementaita. Notably, the heat-altered DOM of ancient autochthonous derivation could represent an overlooked source of aliphatic organic carbon for connected lentic environments, with a potential direct impact on nutrient cycling in lakes that receive geothermal water inputs.

Microbial enzyme activities on organic polymers were tested as possible sentinels of anthropic and natural forcings during a two-year study in two coastal Antarctic areas (Road Bay and Tethys Bay respectively). In Road Bay high proteolytic activity rates were measured at a site impacted by the Italian research station sewage, due to faecal wastes; in Tethys Bay low salinity waters related to glacier presence were characterized by high enzyme activities probably associated to detritus from ice melting.

Polyphenols are natural antioxidant compounds ubiquitously found in plants and, thus, ever present in human nutrition (tea, wine, chocolate, fruits and vegetables are typical examples of polyphenol-rich foods). Widespread evidence indicate that polyphenols exert strong antioxidant, anti-inflammatory, anti-microbial and anti-cancer activities, and thus, they are generally regarded to as all-purpose beneficial nutraceuticals or supplements whose use can only have a positive influence on the body. A closer look to the large body of results of years of investigations, however, present a more complex scenario where polyphenols exert different and, sometimes, paradoxical effects depending on dose, target system and cell type and the biological status of the target cell. Particularly, the immunomodulatory potential of polyphenols presents two opposite faces to researchers trying to evaluate their usability in future cancer therapies: on one hand, these compounds could be beneficial suppressors of peri-tumoral inflammation that fuels cancer growth. On the other hand, they might suppress immunotherapeutic approaches and give rise to immunosuppressive cell clones that, in turn, would aid tumor growth and dissemination. In this review, we summarize knowledge of the immunomodulatory effects of polyphenols with a particular focus on cancer microenvironment and immunotherapy, highlighting conceptual pitfalls and delicate cell-specific effects in order to aid the design of future therapies involving polyphenols as chemoadjuvants.

To date, microbial biofilm communities in Terra Nova Bay (Ross Sea, Antarctica)are still scarcely explored regarding their structure and function; moreover, no data are currently available regarding possible effects of environmental and/or anthropic forcing on microbial colonization. Funded by the Italian National Programme of Antarctic Research (PNRA16_00105), the project ANT-Biofilm started in November 2017 with the overall objective of studying microbial colonization of benthic environments, focusing on microbial abundance, activity and diversity, and larval settlement in response to natural or anthropogenic disturbances. Here we present the preliminary results on the structural characteristics and diversity of the microbial communities associated to two artificial substrates deployed in a coastal Antarctic environment of the Ross Sea, close to the Italian Research Station Mario Zucchelli. Polyethylene (PVC) panels and polyethylene (PE) coupons were placed at -5 and -20 m of depth in two sites in Terra Nova Bay (Road Bay and Tethys Bay, differently impacted by anthropic pressure) and collected after 3, 9 and 12 months during the 33 Italian Expedition. Bacterial community composition was studied at single cell level, by Catalysed Reporter Deposition Fluorescence In Situ Hybridization (CARD-FISH) combined with Confocal Laser Scanning Microscopy (CLSM). Moreover 16s rRNA gene sequencing was applied to compare the diversity of the planktonic and substrate-associated microbial communities.

Microbial biofilms play a key role in substrate colonization in aquatic environments, as hot spots of biodiversity and sources of secondary metabolites with biotechnological potential. In Terra Nova Bay (Ross Sea, Antarctica), microbial biofilm communities are under-explored in their structure and functions; particularly, their response to environmental and/or anthropogenic forcings remains to be elucidated yet. Funded by National Antarctic Research Program (XXXIII Italian expedition), the ANT-Biofilm project "Microbial colonization of benthic ANTarctic environments: response of microbial abundances, diversity, activities and larval settlement to natural or anthropogenic disturbances and search for secondary metabolites" (PNRA16_00105) includes short and long term (3-12 months) experiments in two bays (Road Bay and Tethys Bay) characterized by anthropogenic (i.e. sewage) and natural (i.e. low salinity) stressors, respectively. Total, viable and respiring prokaryotes, culturable bacteria, potential enzymatic activity rates, physiological community profiles, microalgae and macrobenthic community are studied. Selected biofilm samples will be sequenced and analyzed by hybridization (i.e. Card-FISH) and bacterial isolates screened for antibiotic resistance and metabolite production. Physical-chemical environmental characterization will be performed. This contribution reports the preliminary results obtained by the four Research Units during the short term experiments.

Volcanic lakes are characterized by physicochemical favorable conditions for the development of reservoirs of C-bearing greenhouse gases that can be dispersed to air during occasional rollover events. By combining a microbiological and geochemical approach, we showed that the chemistry of the CO2- and CH4-rich gas reservoir hosted within the meromictic Lake Averno (Campi Flegrei, southern Italy) are related to the microbial niche differentiation along the vertical water column. The simultaneous occurrence of diverse functional groups of microbes operating under different conditions suggests that these habitats harbor complex microbial consortia that impact on the production and consumption of greenhouse gases. In the epilimnion, the activity of aerobic methanotrophic bacteria and photosynthetic biota, together with CO2 dissolution at relatively high pH, enhanced CO2- and CH4 consumption, which also occurred in the hypolimnion. Moreover, results from computations carried out to evaluate the dependence of the lake stability on the CO2/CH4 ratios, suggested that the water density vertical gradient was mainly controlled by salinity and temperature, whereas the effect of dissolved gases was minor, excepting if extremely high increases of CH4 are admitted. Therefore, biological processes, controlling the composition of CO2 and CH4, contributed to stabilize the lake stratification of the lake. Overall, Lake Averno, and supposedly the numerous worldwide distributed volcanic lakes having similar features (namely bio-activity lakes), acts as a sink for the CO2 supplied from the hydrothermal/magmatic system, displaying a significant influence on the local carbon budget.

Guidelines established preoperative cardiac management of the patient undergoing non-cardiac surgery in hospitalization. Regarding the patients undergoing the surgery in DS, the management is not defined. Aim of this study was to evaluate the appropriateness of the cardiological consultation requested by the patients undergoing surgery with this method.We examined the request of cardiological evaluation for patient admitted to DS of Sant'Andrea Hospital in Rome. We have considered: age, sex, clinic history, simpthomatology, electrocardiogram, cardiovascular objectivity, hemodynamic stability, comorbidity, therapy, type of the surgery, the motivation of the request.Of 2350 patients, 495 patients (21%) have been undergone the preoperative cardiologic consultation. The request was resulted as unnecessary for 432 (87.2%) patients, appropriate for 63 (12.7%): 4 that had the ischemic heart disease without knowing this, 6 with severe hypertension; 2 with mitral valve prolapse and valvular regurgitation; 34 with congestive heart failure; 6 with the alterations in EKG : 3 with "Brugada pattern"; 1 with Pace Maker (PMK) that had to be reprogrammed before the operation; 3 under dual antiplatelet therapy; 7 that were taking the oral anticoagulant therapy. Cardiac complications occurred just in one case with patient suffering dilated cardiomyopathy, diabetes and hypertension; during the cataract surgery was presented the abrupt increase of blood pressure and left ventricular failure.Preoperative cardiologic evaluation results as useless in most patients. However, in some particular situations had allowed the diagnosis of heart disease for the patients who did not know to have it.

We studied the diversity, community composition and activity of the primary microbial colonizers of the water above freshly re-wetted sediments from a temporary river. Dried sediments, collected from Mulargia River (Sardinia, Italy), were covered with sterile freshwater in triplicate microcosms, and changes of the planktonic microbial assemblage were monitored over a 48 h period. During the first 9 h bacterial abundance was low (1.5 ¥ 104 cells ml-1); it increased to 3.4 ¥ 106 cells ml-1 after 28 h and did not change thereafter. Approximately 20% of bacteria exhibited DNA de novo synthesis already after 9 h of incubation. Changes of the ratios of 3H-leucine to 3H-thymidine incorporation rates indicated a shift of growth patterns during the experiment. Extracellular enzyme activity showed a maximum at 48 h with aminopeptidase activity (430.8 22.6 nmol MCA l-1 h-1) significantly higher than alkaline phosphatase (98.6 4.3 nmol MUF l-1 h-1). The primary microbial colonizers of the overlaying water - as determined by 16S rRNA gene sequence analysis - were related to at least six different phylogenetic lineages of Bacilli and to Alphaproteobacteria (Brevundimonas spp. and Caulobacter spp.). Large bacterial cells affiliated to one clade of Bacillus sp. were rare in the dried sediments, but constituted the majority of the planktonic microbial assemblage and of cells with detectable DNA-synthesis until 28 h after re-wetting. Their community contribution decreased in parallel with a rise of flagellated and ciliated protists. Estimates based on cell production rates suggested that the rapidlyenriched Bacillus sp. suffered disproportionally high loss rates from selective predation, thus favouring the establishment of a more heterogenic assemblage of microbes (consisting of Proteobacteria, Actinobacteria and Cytophaga-Flavobacteria). Our results suggest that the primary microbial colonizers of the water above dried sediments are passively released into the plankton and that their high growth potential is counteracted by the activity of bacterivorous protists.

In Mediterranean intermittent streams, the hydrological fragmentation in summer and the successive water flow reconvergence in autumn allow exploring how local processes shape the microbial community within the same habitat. The objectives of this study were to determine how bacterial community composition responded to hydrological fragmentation in summer, and to evaluate whether the seasonal shifts in community composition predominate over the effects of episodic habitat fragmentation. The bacterial community was assessed along the intermittent stream Fuirosos (Spain), at different levels of phylogenetic resolution by in situ hybridization, fingerprinting, and 16S rRNA gene sequencing. The hydrological fragmentation of the stream network strongly altered the biogeochemical conditions with the depletion of oxidized solutes and caused changes in dissolved organic carbon characteristics. In the isolated ponds, beta-Proteobacteria and Actinobacteria increased their abundance with a gradual reduction of the alpha-diversity as pond isolation time increased. Moreover, fingerprinting analysis clearly showed a shift in community composition between summer and autumn. In the context of a seasonal shift, the temporary stream fragmentation simultaneously reduced the microbial dispersion and affected local environmental conditions (shift in redox regime and quality of the dissolved organic matter) tightly shaping the bacterioplankton community composition.

For a long time the bacterial phylum of Chlamydiae exclusively consisted of one family of obligate intracellular bacteria, the Chlamydiaceae, which encompassed causative agents of severe diseases. In the 1990s, environmental chlamydiae were discovered as symbionts of free-living amoebae and other eukaryotic hosts. During a sampling campaign in September 2008, while monitoring Planctomycetes, we retrieved 20 almost full-length 16S rRNA gene sequences affiliated with Chlamydiales from a lake at the Tyrrhenian coast of central Italy (Lago di Paola, Latium). Two main clusters were identified. The nine sequences within the tight cluster I shared ~98% identity, just like the six sequences of cluster II. The 16S rRNA sequence identity between the two novel groups was with 88% higher than with all known families of the order Chlamydiales. Four types of less frequent chlamydial 16S rRNA sequences were also detected. Two oligonucleotide probes were designed, and optimized. Chl282 targets the cluster I and almost all other Chlamydiales, while Chl282bis targets the cluster II and few other sequences. By catalysed reporter deposition fluorescence in situ hybridization (CARD-FISH), we identified in the Lago di Paola picoplankton abundant tiny cells with dot-shaped morphology and, interestingly, rarely also protists with intracellular pleomorphic chlamydiae. Abundances of the novel chlamydial clusters were up to 5 ¥ 104 cells per millilitre. The two clusters were also detected in similar numbers during a second sampling in October 2010. This confirmed the relevance of the two newly described clusters of chlamydiae in Lago di Paola, not only enlarging the knowledge on the biodiversity

In this paper, we extend the classical Variable Size Bin Packing Problem (VS-BPP) by adding time features to both bins and items. Speciffically, the bins act as machines that process the assigned batch of items with a fixed processing time. Hence, the items are available for processing at given times and are penalized for tardiness. Within this extension we also consider a stochastic variant, where the arrival times of the items have a discrete probability distribution. To solve these models, we build a Markov Chain Monte Carlo (MCMC) heuristic. We provide numerical tests to show the different decision making processes when time constraints and stochasticity are added to VSBPP instances. The results show that these new models entail safer and higher cost solutions. We also compare the performance of the MCMC heuristic and an industrial solver to show the effciency and the effcacy of our method.