Imaging-based prostate cancer screening among BRCA mutation carriers-results from the first round of screening.

BACKGROUND: Male-carriers of BRCA1/2 gene mutations have an increased risk of prostate cancer (PCa) with a more aggressive phenotype. Current screening-guidelines suggest the use of prostate-specific antigen (PSA) only among BRCA2 carriers. Female carriers have extensive guidelines that include imaging. Our objective was to test the prevalence of PCa among BRCA carriers and examine screening strategies, using PSA and multiparametric magnetic resonance imaging (mpMRI). PATIENTS AND METHODS: We recruited men aged 40-70 years with BRCA1/2 germline mutations and no prior history of prostate biopsy. All men underwent an initial round of screening which included PSA, and prostate mpMRI. PSA was considered elevated using an age-stratified threshold of ≥1 ng/ml for 40-50 years of age, ≥2 ng/ml for 50-60 years of age, and 2.5 ng/ml for 60-70 years of age. Men with elevated PSA and/or suspicious lesion on mpMRI were offered a prostate biopsy. PSA levels, MRI findings, PCa incidence, and tumor characteristics were evaluated. Decision curve analysis was used to compare screening strategies. RESULTS: We recruited 188 men (108 BRCA1, 80 BRCA2), mean age 54 years (9.8). One hundred and ten (57%) had either elevated age-stratified PSA (75; 40%), a suspicious MRI lesion (67; 36%), or both (32; 17%). Of these, 92 (85%) agreed to perform a prostate biopsy. Sixteen (8.5%) were diagnosed with PCa; 44% of the tumors were classified as intermediate- or high-risk disease. mpMRI-based screening missed only one of the cancers (6%), while age-stratified PSA would have missed five (31%). Decision curve analysis showed that mpMRI screening, regardless of PSA, had the highest net benefit for PCa diagnosis, especially among men younger than 55 years of age. We found no difference in the risk of PCa between BRCA1 and BRCA2 (8.3% versus 8.7%, P = 0.91). Ninety percent had a Jewish founder mutation, thus the results cannot be generalized to all ethnic groups. CONCLUSIONS: PCa is prevalent among BRCA carriers. Age may affect screening strategy for PCa in this population. Young carriers could benefit from initial MRI screening. BRCA carriers aged older than 55 years should use PSA and be referred to mpMRI if elevated. TRIAL REGISTRATION: ClinicalTrial.gov ID: NCT02053805.

NaCl concentration in the medium modulates the secretion of active EmpA protease in Vibrio anguillarum at post-transcriptional level.

AIMS: This study focused on the influence of different amounts of NaCl in the medium in Vibrio anguillarum EmpA protease production at both the transcriptional and post-transcriptional levels. METHODS AND RESULTS: Vibrio anguillarum 975/I was cultivated in cM9 medium with varying concentrations of NaCl: 0·5, 1·5, 3·0%. EmpA protease was monitored in the supernatants by the skim milk test, azocasein assay and Western blot analysis. The empA gene expression was measured by real-time PCR. A mutant strain 975/I defective for the empA gene confirmed the specificity of the response for EmpA protease. Active protease production was induced by 0·5 and 1·5% NaCl-amended media; however, the strain cultivated in 3·0% NaCl was unable to secrete EmpA protease. The quantitative expression of the empA gene was very similar in all tested conditions. CONCLUSIONS: The NaCl concentration in the medium modulates the secretion of active EmpA protease in V. anguillarum at a post-transcriptional level. SIGNIFICANCE AND IMPACT OF THE STUDY: EmpA protease is one of the most important virulence factors in V. anguillarum. We demonstrated the influence of osmotic changes in the regulation of EmpA protease in the V. anguillarum 975/I strain. This finding has an important impact on the evaluation of factors determining the onset of disease in fish.

Application of relative real-time PCR to detect differential expression of virulence genes in Vibrio anguillarum under standard and stressed growth conditions.

In this study, we aimed to understand whether abiotic factors affect the expression of virulence genes in Vibrio anguillarum. We observed the in vitro responses of two Mediterranean strains of V. anguillarum to temperature, NaCl and iron concentration changes. We monitored growth performance and gene transcription levels by comparing the results obtained under stressed conditions (temperatures of 5 °C, 15 °C and 37 °C; NaCl concentrations of 3% and 5%; and iron depletion and excess) with those obtained under standard growth conditions (25 °C, 1.5% NaCl and 0.6 µm of iron). The results showed that the strains respond differently. The strain 975/I was most strongly affected by conditions of 15 °C and iron depletion; these conditions induced increased transcription levels of empA, angR and fatA. Growth of the strain 17/I was inhibited at 15 °C and in iron depletion conditions; this strain also showed dramatic changes in the transcription levels of toxR and tonB2 under increased NaCl concentrations. These results demonstrate that environmental stress affects the expression of virulence genes in V. anguillarum that have implications for the competitiveness, stress tolerance and the ability of V. anguillarum to cause infection.

Bacterial biofilms on medical masks disposed in the marine environment: a hotspot of biological and functional diversity.

The present paper was aimed at investigating the role of disposable medical masks as a substrate for microbial biofilm growth and for the selection of specific microbial traits in highly impacted marine environments. In this view, we have immerged masks in a coastal area affected by a continuous input of artisanal fishery wastes and hydrocarbons pollution caused by intense maritime traffic. Masks maintained one month in the field were colonized by a bacterial community significantly different from that detected in the natural matrices from the same areas (seawater and sediments). The masks served as a viable substrate for the growth and enrichment of phototrophic microorganisms (Oxyphotobacteria), as well as Ruminococcaceae, Gracilibacteria, and Holophageae. In a follow-up investigation, masks previously colonized in the field were transferred in lab-scale microcosms which were supplemented with hydrocarbons and which contained also a piece of a virgin mask. After one month, a shift in the community composition, likely triggered by hydrocarbons addition, was observed in the previously colonized mask, with signatures characteristic of hydrocarbon-degrading microbial groups. Such hydrocarbon-degrading bacteria were also found to colonize the virgin mask. Remarkably, SEM micrographs provided indications of the occurrence of morphological modifications of the surface components of the virgin masks colonized by hydrocarbonoclastic bacteria. Overall, for the first time, we have demonstrated the potential risk for human and animal health determined by the uncorrected disposal of masks which are suitable substrates for pathogens colonization, permanence and spreading. Moreover, we have herein strengthened the knowledge on the role of hydrocarbon-degrading bacteria in the colonization and modification of fossil-based plastics in marine environment.

Populations of heavy fuel oil-degrading marine microbial community in presence of oil sorbent materials.

AIMS: To investigate the feasibility of applying sorbent material X-Oil in marine oil spill mitigation and to survey the interactions of oil, bacteria and sorbent. METHODS AND RESULTS: In a series of microcosms, 25 different treatments including nutrient amendment, bioaugmentation with Alcanivorax borkumensis and application of sorbent were tested. Microbial community dynamics were analysed by DNA fingerprinting methods, RISA and DGGE. Results of this study showed that the microbial communities in microcosms with highly active biodegradation were strongly selected in favour of A. borkumensis. Oxygen consumption measurements in microcosms and gas chromatography of oil samples indicated the fast and intense depletion of linear alkanes as well as high oxygen consumption within 1 week followed by consequent slower degradation of branched and polyaromatic hydrocarbons. CONCLUSION: Under given conditions, A. borkumensis was an essential organism for biodegradation, dominating the biofilm microbial community formation and was the reason of emulsification. SIGNIFICANCE AND IMPACT OF THE STUDY: This study strongly emphasizes the pivotal importance of A. borkumensis as an essential organism in the initial steps of marine hydrocarbon degradation. Interaction with the sorbent material X-Oil proved to be neutral to beneficial for biodegradation and also promoted the growth of yet unknown micro-organisms.

Combining electrokinetic transport and bioremediation for enhanced removal of crude oil from contaminated marine sediments: Results of a long-term, mesocosm-scale experiment.

Marine sediments represent an important sink of harmful petroleum hydrocarbons after an accidental oil spill. Electrobioremediation techniques, which combine electrokinetic transport and biodegradation processes, represent an emerging technological platform for a sustainable remediation of contaminated sediments. Here, we describe the results of a long-term mesocosm-scale electrobioremediation experiment for the treatment of marine sediments contaminated by crude oil. A dimensionally stable anode and a stainless-steel mesh cathode were employed to drive seawater electrolysis at a fixed current density of 11 A/m2. This approach allowed establishing conditions conducive to contaminants biodegradation, as confirmed by the enrichment of Alcanivorax borkumensis cells harboring the alkB-gene and other aerobic hydrocarbonoclastic bacteria. Oil chemistry analyses indicated that aromatic hydrocarbons were primarily removed from the sediment via electroosmosis and low molecular weight alkanes (nC6 to nC10) via biodegradation.

Bioremediation of benzene, toluene, ethylbenzene, xylenes-contaminated soil: a biopile pilot experiment.

AIMS: In this study, we evaluated the removal efficiency of fuel hydrocarbons from a jet fuel contaminated area using bioaugmentation treatment in biopile. METHODS AND RESULTS: The hydrocarbon analysis of the sample revealed total hydrocarbons mainly constituted by benzene, toluene, ethylbenzene, xylenes (BTEX) and heavy aliphatic hydrocarbons. Enrichments of soil sample were performed with BTEX, pristane and fuel JP-5, respectively, selected hydrocarbon-degrading strains, namely Acinetobacter sp., Pseudomonas sp. and Rhodococcus sp. Three hundred litres of culture containing 10(8) cell ml(-1) of each strain and nutrients sprayed on the biopile allowed a removal of 90% of total hydrocarbons in 15 days. Bioremediation process was monitored by observation of the respiration rate and the bacterial abundance and GC-MS analysis. CONCLUSIONS: The efficiency of the treatment in the biopile was considerable. The assessment of microbial activity during the experiment is necessary for interventions targeted to improve environmental parameters such as humidity, temperature, pH and nutrients for optimization of the bioremediation process. SIGNIFICANCE AND IMPACT OF THE STUDY: A better knowledge of microbial successions at oil-polluted sites is essential for environmental bioremediation. Data obtained in biopile study improve our understanding of processes occurring during oil pollution.

Ferrous iron- and ammonium-rich diffuse vents support habitat-specific communities in a shallow hydrothermal field off the Basiluzzo Islet (Aeolian Volcanic Archipelago).

Ammonium- and Fe(II)-rich fluid flows, known from deep-sea hydrothermal systems, have been extensively studied in the last decades and are considered as sites with high microbial diversity and activity. Their shallow-submarine counterparts, despite their easier accessibility, have so far been under-investigated, and as a consequence, much less is known about microbial communities inhabiting these ecosystems. A field of shallow expulsion of hydrothermal fluids has been discovered at depths of 170-400 meters off the base of the Basiluzzo Islet (Aeolian Volcanic Archipelago, Southern Tyrrhenian Sea). This area consists predominantly of both actively diffusing and inactive 1-3 meters-high structures in the form of vertical pinnacles, steeples and mounds covered by a thick orange to brown crust deposits hosting rich benthic fauna. Integrated morphological, mineralogical, and geochemical analyses revealed that, above all, these crusts are formed by ferrihydrite-type Fe3+ oxyhydroxides. Two cruises in 2013 allowed us to monitor and sampled this novel ecosystem, certainly interesting in terms of shallow-water iron-rich site. The main objective of this work was to characterize the composition of extant communities of iron microbial mats in relation to the environmental setting and the observed patterns of macrofaunal colonization. We demonstrated that iron-rich deposits contain complex and stratified microbial communities with a high proportion of prokaryotes akin to ammonium- and iron-oxidizing chemoautotrophs, belonging to Thaumarchaeota, Nitrospira, and Zetaproteobacteria. Colonizers of iron-rich mounds, while composed of the common macrobenthic grazers, predators, filter-feeders, and tube-dwellers with no representatives of vent endemic fauna, differed from the surrounding populations. Thus, it is very likely that reduced electron donors (Fe2+ and NH4+ ) are important energy sources in supporting primary production in microbial mats, which form a habitat-specific trophic base of the whole Basiluzzo hydrothermal ecosystem, including macrobenthic fauna.

Bioremediation technologies for polluted seawater sampled after an oil-spill in Taranto Gulf (Italy): A comparison of biostimulation, bioaugmentation and use of a washing agent in microcosm studies.

One of the main challenges of bioremediation is to define efficient protocols having a low environmental impact. We have investigated the effect of three treatments in oily-seawater after a real oil-spill occurred in the Gulf of Taranto (Italy). Biostimulation with inorganic nutrients allowed the biodegradation of the 73±2.4% of hydrocarbons, bioaugmentation with a selected hydrocarbonoclastic consortium consisting of Alcanivorax borkumensis, Alcanivorax dieselolei, Marinobacter hydrocarbonoclasticus, Cycloclasticus sp. 78-ME and Thalassolituus oleivorans degraded 79±3.2%, while the addition of nutrients and a washing agent has allowed the degradation of the 69±2.6%. On the other hand, microbial community was severely affected by the addition of the washing agent and the same product seemed to inhibit the growth of the majority of strains composing the selected consortium at the tested concentration. The use of dispersant should be accurately evaluated also considering its effect on the principal actors of biodegradation.

Complete voltage recovery in quantum dot solar cells due to suppression of electron capture.

Extensive investigations in recent years have shown that addition of quantum dots (QDs) to a single-junction solar cell decreases the open circuit voltage, VOC, with respect to the reference cell without QDs. Despite numerous efforts, the complete voltage recovery in QD cells has been demonstrated only at low temperatures. To minimize the VOC reduction, we propose and investigate a new approach that combines nanoscale engineering of the band structure and the potential profile. Our studies of GaAs solar cells with various InAs QD media demonstrate that the main cause of the VOC reduction is the fast capture of photoelectrons from the GaAs conduction band (CB) to the localized states in QDs. As the photoelectron capture into QDs is mainly realized via the wetting layers (WLs), we substantially reduced the WLs using two monolayer AlAs capping of QDs. In the structures with reduced WLs, the direct CB-to-QD capture is further suppressed due to charging of QDs via doping of the interdot space. The QD devices with suppressed photoelectron capture show the same VOC as the GaAs reference cell together with some improvements in the short circuit current.

Biodegradation potentiality of psychrophilic bacterial strain Oleispira antarctica RB-8(T).

The present study is focused on assessing the growth and hydrocarbon-degrading capability of the psychrophilic strain Oleispira antarctica RB-8(T). This study considered six hydrocarbon mixtures that were tested for 22days at two different cultivation temperatures (4 and 15°C). During the incubation period, six sub-aliquots of each culture at different times were processed for total bacterial abundance and GC-FID (gas chromatography-flame ionization detection) hydrocarbon analysis. Results from DNA extraction and DAPI (4',6-diamidino-2-phenylindole) staining showed a linear increase during the first 18days of the experiment in almost all the substrates used; both techniques showed a good match, but the difference in values obtained was approximately one order of magnitude. GC-FID results revealed a substantial hydrocarbon degradation rate in almost all hydrocarbon sources and in particular at 15°C rather than 4°C (for commercial oil engine, oily waste, fuel jet, and crude oil). A more efficient degradation was observed in cultures grown with diesel and bilge water at 4°C.

Novel glycine containing glucolipids from the alkane using bacterium Alcanivorax borkumensis.

The polar lipids from the hydrocarbon using and biosurfactant-producing bacterium Alcanivorax borkumensis were isolated and identified by mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy. The biosurfactant produced by this species is an anionic glucose lipid with a tetrameric oxyacyl side chain. The glycolipids extracted from the cell wall consist of this biosurfactant N-terminally esterified with glycine. Ten different derivatives of this lipid type were identified and their structures elucidated by MSMS. They vary by the chain length of one or two of the four beta-hydroxy fatty acids (C6, C8 and C10) and by the location of these different fatty acids within the molecule. All compounds are reported here for the first time. In addition to these glycolipids, three different phosphatidylglycerols were identified. While these lipids were found in all strains of A. borkumensis, the relative abundances of the different lipids vary between the strains.

Structural characterization of lichenysin A components by fast atom bombardment tandem mass spectrometry.

The structural characterization of the cyclic lipoheptapeptide surfactant lichenysin A components, produced by Bacillus licheniformis strains via the non-ribosomal pathway on a corresponding peptide synthetase, was carried out using a tandem mass spectrometry (MS/MS) under fast atom bombardment (FAB) conditions. Based on the analysis of the collision-induced fragment-ion spectrum of the single charged molecular ions of both native and partially hydrolyzed forms of lipopeptide, a new general structure of lichenysin A components was elucidated. It varies from previously proposed structure by having in the peptide portion of lipopeptide the L-Gln-1 and L-Asp-5 residues instead of L-Glu-1 and L-Asn-5. The verified chemical structure of lichenysin A was found to be reflected in the structural organization of the corresponding lichenysin A synthetase, LchA, described recently.

A putative lichenysin A synthetase operon in Bacillus licheniformis: initial characterization.

Certain Bacillus licheniformis strains isolated from oil wells have been shown to produce a very effective biosurfactant, lichenysin A, which is structurally similar to another less active lipopeptide, surfactin. Surfactin, like many small peptides in prokaryotes and lower eukaryotes, is synthesized non-ribosomally by multi-enzyme peptide synthetase complex. Analysis of several peptide synthetases of bacterial and fungal origin has revealed a high degree of sequence conservation. Two 35-mer oligonucleotides derived from highly conserved motifs ('core I' and 'core II') of surfactin synthetase were used to identify the cloned putative operon of lichenysin A synthetase lchA from B. licheniformis BNP29, a strain not amenable to genetic manipulation in a BAC system (F-plasmid-based bacterial artificial chromosome) based on Escherichia coli and its single-copy plasmid F-factor. A 32.4 kb fragment containing lichenysin A biosynthesis locus was sequenced and analysed. The structural architecture of putative lichenysin A synthetase protein containing seven amino acid (aa) activation-thiolation, two epimerization and one thioesterase domains is discussed in terms of its similarity to surfactin and other peptide synthetases. The 100 aa peptide chain situated between the highly conserved signature sequences FDXX and NXYGPTE(IV)X within amino acid binding domains of peptide synthetases is proposed to be a minimal block dictating the substrate specificity of the enzymes. A new operon-type structure has been localized directly upstream from the lichenysin A synthetase genes which, on the basis of sequence determination, potentially encode a four-member ABC-type transport system involved in product secretion.

ComA-dependent transcriptional activation of lichenysin A synthetase promoter in Bacillus subtilis cells.

ComA is a DNA-binding activator protein which is required for the transcription of several late-growth phase expressed genes including srfA, an operon needed for the development of genetic competence, efficient sporulation, and surfactin production in Bacillus subtilis (B. subtilis). We show here that the ComA protein can also recognize the promoter regulatory region of the lchA, lichenysin A synthetase operon, found in. Bacillus licheniformis (B. licheniformis) when introduced into B. subtilis cells. Mutational analysis of this region suggests that a palindromic sequence upstream of the lchA promoter may be the target for ComA-dependent transcriptional activation. Considering that the comA operon is present in the B. licheniformis chromosome, we propose the similar mechanism of transcriptional activation of the lichenysin A synthetase operon.

Hemorrhagic moyamoya disease during pregnancy.

BACKGROUND: Intracranial hemorrhage in pregnant patients with Moyamoya disease is rare. We review the case of one such patient who presented with pre-eclampsia and a catastrophic intracerebral hemorrhage in order to highlight the associated management difficulties. METHODS: A case of a pregnant (31 weeks) female brought to the emergency department with hypertension and a progressive decrease in her level of consciousness is presented. She rapidly developed a dilated right pupil and left extensor posturing. A CT scan of her head showed a large putamenal intracerebral hemorrhage. She was intubated, ventilated and given intravenous mannitol and magnesium sulfate. She underwent a simultaneous craniotomy and Cesarean section. Post-operatively the patient's ICP and jugular venous saturation were monitored in the intensive care unit. RESULTS: The patient delivered a 1185 g infant who did well. The patient's ICP was well controlled until the tenth post-operative day when she developed malignant brain edema and died. CONCLUSION: This case highlights three important points. First, simultaneous craniotomy and Cesarean section can be performed. Second, intraoperative control of bleeding Moyamoya vessels is described. Third, the difficult post-operative management of these cases is highlighted. The literature regarding Moyamoya disease and pregnancy is reviewed and some recommendations for the management of this rare but potentially deadly condition are presented.

Characterization of antarctic hydrocarbon-degrading bacteria capable of producing bioemulsifiers.

During screening for biosurfactant-producing, n-alkane-degrading marine bacteria, two heterotrophic bacterial strains were isolated from enriched mixed cultures, obtained from Terra Nova Bay (Ross sea, Antarctica) by using aliphatic and artomatic hydrocarbons as the principal carbon source. These gram-positive, aerobic, cocci-shaped bacteria use a various number of organic compounds, including aliphatic hydrocarbons, volatile fatty acids, and biphenyl. During cultivation on n-alkanes as sole source of carbon and energy, all strains produced both an extracellular and cell-bound surface-active mixture of trehalose lipids which reduced the surface tension of water from 72 mN/m to 32mN/m. This class of glycolipids was found to be produced only by marine rhodococci. The 16S-rRNA gene sequence analysis showed that both strains are members of the G + C rich gram-positive group of the phylum Proteobacteria and was found to be almost identical to that of Rhodococcus fascians DSM 20669. The potential of these strains for in situ bioremediation of contaminated cold marine environment is discussed in the present study.

Effect of novel biosurfactants on biodegradation of polychlorinated biphenyls by pure and mixed bacterial cultures.

A study was conducted to determine the potential positive effect of novel biosurfactants on the enhancement of Aroclor 1248 metabolization in both in vitro and in situ experiments. Among two lipopeptides tested the highest activity was found in experiments with a hydrolytically opened form of lichenysin A. Lichenysin A itself did not enhance the degradation activity of chosen microorganism-degraders and in most cases inhibited their PCB mineralization rates. Glucolipid surfactant from marine bacterium Alcanivorax borkumensis showed in several tests a strong enhancing effect on microbial metabolization of Aroclor 1248 congeners. Biosurfactants appeared to act very specifically, i.e. depending on strain and concentration used. Experiments set up with soil samples did not give a clear answer whether bioemulsifiers applied at low concentration could sufficiently increase the rates of biodegradation in situ. Only A. borkumiensis glucose lipid caused the most marked enhancement of Aroclor 1248 metabolization in soil microcosm. We suggest that taking into account the specificity of surface- and biological activities of various biosurfactants they may promote the mineralization of sorbed PCBs in polluted soils, when the optimized biosurfactant-degrader combination is used.

Tumefactive demyelination and a malignant course in an MS patient during and following fingolimod therapy.

Finglimod, a sphingosine 1-phosphate receptor modulator, is the first orally administered therapy approved for prophylaxis in multiple sclerosis (MS). Several reports in the last two years suggested that it might be associated with severe augmentation of disease activity upon initiation or discontinuation of therapy. We present an MS patient who developed a giant cavitating brain lesion under fingolimod and in whom cessation of therapy was associated with a very active course. Brain biopsy revealed the lesion to be due to an active demyelinating inflammatory process. With the current wave of immunosuppressive treatments for MS, there is a need to be vigilant to side effects and risks not identified in large multicenter trials, collect the data and set guidelines and precautions for present and future medications.

Alcanivorax borkumensis produces an extracellular siderophore in iron-limitation condition maintaining the hydrocarbon-degradation efficiency.

Obligate marine hydrocarbonoclastic bacteria possess genetic and physiological features to use hydrocarbons as sole source of carbon and to compete for the uptake of nutrients in usually nutrient-depleted marine habitats. In the present work we have studied the siderophore-based iron uptake systems in Alcanivorax borkumensis SK2 and their functioning during biodegradation of an aliphatic hydrocarbon, tetradecane, under iron limitation conditions. The antiSMASH analysis of SK2 genome revealed the presence of two different putative operons of siderophore synthetases. Search for the predicted core structures indicated that one siderophore is clearly affiliated to the family of complex oligopeptidic siderophores possessing an Orn-Ser-Orn carboxyl motif whereas the second one is likely to belong to the family of SA (salicylic acid)-based siderophores. Analyzing the supernatant of SK2 culture, an extracellular siderophore was identified and its structure was resolved. Thus, along with the recently described membrane-associated amphiphilic tetrapeptidic siderophore amphibactin, strain SK2 additionally produces an extracellular type of iron-chelating molecule with structural similarity to pseudomonins. Comparative Q-PCR analysis of siderophore synthetases demonstrated their significant up-regulation in iron-depleted medium. Different expression patterns were recorded for two operons during the early and late exponential phases of growth, suggesting a different function of these two siderophores under iron-depleted conditions.