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Purpose: To investigate the influence of germline succinate dehydrogenase (SDHx) pathogenic variants on 6-[18F]-fluoro-3,4-dihydroxyphenylalanine (18F-DOPA) Positron Emission Tomography (PET) radiomic signature of head and neck paragangliomas (HNPGLs). Methods: Forty-seven patients (20 SDHpathogenic variants carriers) harboring 55 HNPGLs were retrospectively included. HNPGLs were delineated using Nestle adaptive threshold. 128 radiomic features were extracted and harmonized to correct for batch effects. Principal Component Analysis (PCA) was performed to remove redundancy and avoid collinearity. The most representative feature of each component was tested with multivariate stepwise logistic binary regression analysis (LBRA) to identify variables predictive of genetic status. Results: 18F-DOPA Positron Emission Tomography/Computed Tomography (PET/CT) detected 28/29 carotid body HNPGLs, 23/23 jugulotympanic HNPGLs, and 4/4 vagal HNPGLs. SUVmax was significantly higher in SDH-related HNPGLs (p= 0.003). PCA allowed identification of 4 Components. The most representative variables of Component 1 and 2 (including intensity and intensity-related textural features, and not intensity-related textural features, respectively) were Intensity-based (IB)-SUVmedian and Grey Level Run Length Matrix-Long Run Low Gray Level Emphasis (GLRLM-LRLGLE). SDHxHNPGLs exhibited higher activity scores and more homogeneous texture. At patient level, SDHxcases showed significantly higher IB-SUVmedian values (p< 0.001), and lower GLRLM-LRLGLE than sporadic patients (p= 0.005). IB-SUVmedian was found to be an independent predictor of genetic status at lesion (71.0%) and patient level (77.8%). Conclusion: The present study pioneers the application of 18F-DOPA PET radiomics for HNPGLs, suggesting the influence of germline SDHpathogenic variants on 18F-FDOPA uptake intensity and textural heterogeneity. Integrating radiomics with genetic data provides new insights into the correlation between PET features and underlying molecular dysregulation.

This article introduces a sequential Monte-Carlo simulation method (MCS) based on flow networks to represent decentralized power systems and evaluate the reliability and availability of their topologies. It can be used to provide a comparison basis during the system design phase. The method can be employed to simulate a variety of types of decentralized local power systems. It is able to simulate bidirectional, radial, and meshed systems with both repairable and nonrepairable elements. Examples of elements that can be simulated include power sources, loads, and energy-storage units. The determination of system success is performed using a minimum-cost-maximum-flow graph algorithm that calculates the power delivered to the system loads given the state of the system components. If the loads are being properly supplied, the system is deemed functional. The simulation can accommodate additional sets of rules for system success if needed. The method can generate a variety of indices for system availability and reliability based on the system topology and the parameters of its individual components. Three example systems are presented and simulated to showcase the method's capabilities.

The effects of size, toasting degree, and time of contact on the release of volatile compounds from Quercus alba(L.) chips during a simulated fermentation and post-fermentative process were studied. The results obtained indicated that the large-size chips favored the release of furfural and furfuryl alcohol, while the small ones increased the concentration of cyclotene and maltol. The interaction between chip size and time of contact showed that the small-size chips are more sensitive to the increase of ethanol concentration for the extraction rate of some compounds (furfural, vanillin, maltol, cyclotene, whiskey lactones, and eugenol) compared to the large-size ones, increasing their concentrations at the end of maceration. The toasting degree of oak chips had a different influence on the volatile compounds studied. Cyclotene and guaiacol concentrations increased with the toasting intensity, whereas the extracted concentration of all compounds increased from light to medium-toasted chips, except for eugenol, and then decreased by further increasing the toasting level for 5-methylfurfural, whiskey lactones, eugenol, and only using high-level toasted chips for furfuryl alcohol, maltol, and vanillin. A possible protection effect of the chip size toward the possible degradation or volatilization losses of furfural for high toasting degrees was observed.

Transforaminal lumbar interbody fusion (TLIF) cages are used to reduce compression on the neural tissue of the spine and to restore the intervertebral space. Today, these medical devices can be advantageously obtained by additive manufacturing and consist of one or more lattice structures, which allow for a substantial improvement of the osseointegration process. Due to the small sizes and, above all, the fine level of detail of the lattice structure, traditional investigation methods applied for evaluating the mechanical behavior of such components are difficult to employ. A promising alternative is noncontact optical measurement techniques. This work aims to evaluate the feasibility of digital image correlation (DIC) to study the mechanical response of small and complex 3-D medical protheses, specifically of the TLIF cages structures. A cage was loaded statically, using two dedicated coupling elements, to reproduce the physiological mechanical behavior of the lumbar area of the spine. Both the displacement and the strain fields were measured on three regions of the sample. Load-deflection curves, computed by DIC, have been compared with those obtained by a testing machine, and a good agreement was observed. The results highlighted a severe overstress of the lattice structure, which eventually might lead to local failure of the trabeculae, causing injury to the vertebrae, the bones, and the connective tissues of the spine.

The impact of prefermentative addition of five single-enzyme activities (pectin lyase, polygalacturonase, pectin methyl esterase, xylanase, and arabinase) on the phenolic content, colour characteristics, and volatile composition of grape musts resulting from pellicular maceration of Chardonnay, Arneis, Greco, and Falanghina white varieties was studied with the aim of enhancing aroma composition without negatively affecting colour perception. In addition, standard physicochemical parameters were determined. Pectin lyase, polygalacturonase, and arabinase enzymes reduced the must browning, when compared with untreated control, as reported by lower total polyphenol index, absorbance at 420 nm, and a* colour coordinate for all varieties tested. Regarding the volatile composition determined by solid-phase extraction and GC-MS analysis, variety effect was observed for the enzyme treatments studied. The concentration of free vanillin decreased significantly in these last three varieties using polygalacturonase and arabinase treatments whereas 4-vinylguaiacol increased in pectin lyase-treated samples. Free terpene compounds, such as furan linalool oxide, increased in Chardonnay and Falanghina varieties using polygalacturonase, xylanase, and arabinase for the second variety whereas pectin lyase for the first one. Contrarily, glycosylated terpenes, such us (Z)-8-hydroxylinalool, decreased when using pectin lyase and xylanase for Arneis; however, it also occurred for Falanghina using polygalacturonase treatment. The xylanase activity influenced mostly the volatile composition of the Arneis variety whereas arabinase did for Greco and Falanghina. The differences between enzyme-treated grape musts and control samples were less evident on the Chardonnay variety. Therefore, enzyme activity can affect the volatile composition of grape must differently depending on the target variety.

ABSTRACTThe paper examines the topic of identifying eggs freshness through an original approach based on pulsed thermography. The proposed method relies on a short thermal stimulation performed by means of a xenon flash, which rises up the temperature of the egg of less than 1°C. The entire process requires about 1 s, thus providing an effective quality control tool for assessing the freshness of eggs intended for human consumption. The identification and evaluation procedure has been automated by developing a dedicated image processing algorithm, based on a morphological operator with ‘white top hat’ transformation. The software performs a series of preliminary operations on the acquired thermograms and returns an estimation of the air chamber projections, that are correlated to egg degradation and weight reduction.

Convergence and subduction started in the Late Paleocene, to the east of New Caledonia in the South Loyalty Basin/Loyalty Basin, leading to the formation of the Subduction–Obduction Complex of Grande Terre. Convergence during the Eocene consumed the oceanic South Loyalty Basin and the northeasternmost margin of Zealandia (the Norfolk Ridge). The attempted subduction of the Norfolk Ridge eventually led to the end-Eocene obduction. Intra-oceanic subduction started in the South Loyalty Basin, as indicated by high-temperature amphibolite (56 Ma), boninite and adakite series dykes (55–50 Ma) and changes in the sedimentation regime (55 Ma). The South Loyalty Basin and its margin were dragged to a maximum depth of 70 km, forming the high-pressure–low-temperature Pouébo Terrane and the Diahot–Panié Metamorphic Complex, before being exhumed at 38–34 Ma. The obduction complex was formed by the stacking from NE to SW of several allochthonous units over autochthonous Zealandia, including the Montagnes Blanches Nappe (Norfolk Ridge crust), the Poya Terrane (the crust of the South Loyalty Basin) and the Peridotite Nappe (the mantle lithosphere of the Loyalty Basin). A model of continental subduction accepted by most researchers is proposed and discussed. Offshore continuations and comparable units in Papua New Guinea and New Zealand are presented.

Bacterial resistance represents a major health threat worldwide, and the development of new therapeutics, including innovative antibiotics, is urgently needed. We describe a discovery platform, centered on in silicoscreening and in vivobioluminescence resonance energy transfer in yeast cells, for the identification of new antimicrobials that, by targeting the protein–protein interaction between the β′-subunit and the initiation factor σ70of bacterial RNA polymerase, inhibit holoenzyme assembly and promoter-specific transcription. Out of 34 000 candidate compounds, we identified seven hits capable of interfering with this interaction. Two derivatives of one of these hits proved to be effective in inhibiting transcription in vitroand growth of the Gram-positive pathogens Staphylococcus aureusand Listeria monocytogenes. Upon supplementation of a permeability adjuvant, one derivative also effectively inhibited Escherichia coligrowth. On the basis of the chemical structures of these inhibitors, we generated a ligand-based pharmacophore model that will guide the rational discovery of increasingly effective antibacterial agents.

In the last two decades, we have witnessed an impressive crescendo of non-coding RNA studies, due to both the development of high-throughput RNA-sequencing strategies and an ever-increasing awareness of the involvement of newly discovered ncRNA classes in complex regulatory networks. Together with excitement for the possibility to explore previously unknown layers of gene regulation, these advancements led to the realization of the need for shared criteria of data collection and analysis and for novel integrative perspectives and tools aimed at making biological sense of very large bodies of molecular information. In the last few years, efforts to respond to this need have been devoted mainly to the regulatory interactions involving ncRNAs as direct or indirect regulators of protein-coding mRNAs. Such efforts resulted in the development of new computational tools, allowing the exploitation of the information spread in numerous different ncRNA data sets to interpret transcriptome changes under physiological and pathological cell responses. While experimental validation remains essential to identify key RNA regulatory interactions, the integration of ncRNA big data, in combination with systematic literature mining, is proving to be invaluable in identifying potential new players, biomarkers and therapeutic targets in cancer and other diseases.

OBJECTIVETo analyze the impact of the International Nosocomial Infection Control Consortium (INICC) Multidimensional Approach (IMA) and the INICC Surveillance Online System (ISOS) on central line-associated bloodstream infection (CLABSI) rates in 14 intensive care units (ICUs) in Argentina from January 2014 to April 2017.DESIGNThis prospective, pre–post surveillance study of 3,940 ICU patients was conducted in 11 hospitals in 5 cities in Argentina. During our baseline evaluation, we performed outcome and process surveillance of CLABSI applying Centers for Disease Control and Prevention/National Health Safety Network (CDC/NHSN) definitions. During the intervention, we implemented the IMA through ISOS: (1) a bundle of infection prevention practice interventions, (2) education, (3) outcome surveillance, (4) process surveillance, (5) feedback on CLABSI rates and consequences, and (6) performance feedback of process surveillance. Bivariate and multivariate regression analyses were performed using a logistic regression model to estimate the effect of the intervention on the CLABSI rate.RESULTSDuring the baseline period, 5,118 CL days and 49 CLABSIs were recorded, for a rate of 9.6 CLABSIs per 1,000 central-line (CL) days. During the intervention, 15,659 CL days and 68 CLABSIs were recorded, for a rate of 4.1 CLABSIs per 1,000 CL days. The CLABSI rate was reduced by 57% (incidence density rate: 0.43; 95% confidence interval, 0.34–0.6; P<.001).CONCLUSIONSImplementing IMA through ISOS was associated with a significant reduction in the CLABSI rate in ICUs in Argentina.Infect Control Hosp Epidemiol2018;39:445–451

The bioluminescence resonance energy transfer (BRET) technology is a widely used live cell-based method for monitoring protein-protein interactions as well as conformational changes within proteins or molecular complexes. Considering the emergence of protein-protein interactions as a new promising class of therapeutic targets, we have adapted the BRET method in budding yeast. In this technical note, we describe the advantages of using this simple eukaryotic model rather than mammalian cells to perform high-throughput screening of chemical compound collections: genetic tractability, tolerance to solvent, rapidity, and no need of expensive robotic systems. Here, the HDM2/p53 interaction, related to cancer, is used to highlight the interest of this technology in yeast. Sharing the protocol of this BRET-based assay with the scientific community will extend its application to other protein-protein interactions, even though it is toxic for mammalian cells, in order to discover promising therapeutic candidates.

The bioluminescence resonance energy transfer (BRET) technology is a widely used live cell-based method for monitoring protein-protein interactions as well as conformational changes within proteins or molecular complexes. Considering the emergence of protein-protein interactions as a new promising class of therapeutic targets, we have adapted the BRET method in budding yeast. In this technical note, we describe the advantages of using this simple eukaryotic model rather than mammalian cells to perform high-throughput screening of chemical compound collections: genetic tractability, tolerance to solvent, rapidity, and no need of expensive robotic systems. Here, the HDM2/p53 interaction, related to cancer, is used to highlight the interest of this technology in yeast. Sharing the protocol of this BRET-based assay with the scientific community will extend its application to other protein-protein interactions, even though it is toxic for mammalian cells, in order to discover promising therapeutic candidates.

Hepatitis B virus (HBV)-specific CD8 T cells are functionally exhausted in chronic hepatitis B infection, and this condition can be corrected only partially through the modulation of inhibitory pathways, which suggests that a more complex molecular interplay underlies T cell exhaustion. To gain broader insight into this process and identify additional targets for the restoration of T cell function, we compared the transcriptome profiles of HBV-specific CD8 T cells from patients with acute and chronic disease with those of HBV-specific CD8 T cells from patients able to resolve HBV infection spontaneously and influenza (FLU)-specific CD8 T cells from healthy participants. The results indicate that exhausted HBV-specific CD8 T cells are markedly impaired at multiple levels and show substantial downregulation of various cellular processes centered on extensive mitochondrial alterations. A notable improvement of mitochondrial and antiviral CD8 functions was elicited by mitochondrion-targeted antioxidants, which suggests a central role for reactive oxygen species (ROS) in T cell exhaustion. Thus, mitochondria represent promising targets for novel reconstitution therapies to treat chronic hepatitis B infection.

AbstractA multi-specific approach in fish diet studies provides insight into the complexity of trophic interactions in marine communities. The feeding habits of three gurnard species, Aspitrigla cuculus, Chelidonichthys lucernaand Eutrigla gurnardus(Scorpaeniformes: Triglidae), from the north-middle Adriatic Sea were studied to evaluate prey-resource partitioning amongst species and within species, comparing juveniles’ and adults’ diet for each gurnard species. A total of 1818 specimens (390 A. cuculus, 973 C. lucerna, 455 E. gurnardus) were collected by bottom trawling and they were assigned to size classes (juveniles or adults) on the basis of macroscopic evaluation of the gonads. Stomach contents were analysed. A common dietary preference for Crustacea was found in all species and size classes considered. Nevertheless, gurnards showed distinct feeding behaviour: C. lucernaand E. gurnarduswere generalist-opportunistic predators, showing a varied diet based on epi-benthic, bentho-pelagic and necto-benthic preys belonging to different taxa such as Teleostei and Mollusca, while A. cuculusmay be considered a specialist feeder, feeding almost exclusively on necto-benthic invertebrates. Morisita’s index calculated for critical size classes (juveniles and adults) pointed out differences. At the inter-specific level, possible dietary competition between A. cuculusand E. gurnardus(C > 0.65) was found for all size classes combined, due to the prey abundance of Lophogaster typicus(Crustacea: Mysida). At the intra-specific level, high diet overlap was found between juveniles and adults of C. cuculus(C = 0.98) and between juveniles and adults of E. gurnardus(C > 0.84). In contrast, C. lucernadid not compete with increasing body size (C < 0.20), showing a clear change from crustaceans to fish in its diet preferences. The possibility that A. cuculusand E. gurnardusmay compete for the same prey resources while C. lucernashows food resource partitioning is discussed. Better understanding of the ecology of these coexisting predators should lead to improved conservation and improved fisheries management.

Context:Cystic fibrosis-related diabetes (CFRD) is the most frequent and severe co-morbidity in cystic fibrosis (CF). Presentation and severity are quite variable.Objective:To investigate changes in microRNAs (miRNAs) due to CF transmembrane conductance regulator malfunctioning in vitro, to study the circulating levels of selected miRNAs in serum samples from patients, and to assess their relationships in different age groups with genotype, glucose tolerance state, and at onset of CFRD.Design/Setting/Patients/Interventions:Transcriptional profiling of all known miRNAs in CFBE41o- cells, in their normal counterparts (16HBE14o- cells), and in IB3 cells was performed. A set of miRNAs was differentially expressed in the CF cells. By in silico analysis, four miRNAs (miR-146a, miR-155, miR-370, and miR-708) were selected as potential regulators of the FOXO1gene. Seventy-four CF patients and 50 healthy subjects whose glucose tolerance was characterized by an oral glucose tolerance test were enrolled in the study, and the identified miRNAs were quantified in serum by quantitative RT-PCR.Main Outcome Measurements/Results:A total of 111 miRNAs were differentially expressed in the two CF cell lines. miR-155, miR-370, and miR-708 were up-regulated and miR-146a was down-regulated in vitro, whereas in vivo, miR-146a, miR-155, and miR-370 were up-regulated, and miR-708 was down-regulated. These changes showed relationships with genotype, glucose tolerance state, and onset of CFRD.Conclusions:The data showed significant changes in miRNAs dependent on genotype and glucose tolerance state in CF patients and highlighted some miRNAs of importance in CFRD at onset. miRNAs could explain some of the variability observed in CF.

This study aims to compare in-vitrothe fitting accuracy of implant-supported metal frameworks used for full-arch orthodontic restoration. The hypotheses tested were as follows: (1) for a fixed implant morphology, strains developed within the framework depend on how the framework had been fabricated and (2) stresses transferred to the implant–bone interface are related to the amount of framework misfit. Metal frameworks were fabricated using four different manufacturing techniques: conventional lost-wax casting, resin cement luting, electrospark erosion, and computer-aided design/computer-aided manufacturing milling. Each framework was instrumented with three strain gauges to measure strains developed because of prosthetic misfit, while quantitative photoelastic analysis was used to assess the effect of misfit at the implant–resin interface. All the tested frameworks presented stress polarization around the fixtures. After screw tightening, significantly greater strains were observed in the lost-wax superstructure, while the lowest strains were observed in the luted framework, demonstrating consistent adaptation and passive fitting. No significant difference in stress distribution and marginal fit was found for bars fabricated by either computer-aided design/computer-aided manufacturing or spark erosion. This study suggested that, in spite of known limitations of in-vitrotesting, direct luting of mesostructures and abutments should be the first clinical option for the treatment of complete edentulism, ensuring consistent passive fitting and effective cost–benefit ratio.

Electrochemical methods such as voltammetry and electrochemical impedance spectroscopy are effective for quantifying solid oxide fuel cell (SOFC) operational performance, but not for identifying and monitoring the chemical processes that occur on the electrodes’ surface, which are thought to be strictly related to the SOFCs’ efficiency. Because of their high operating temperature, mechanical failure or cathode delamination is a common shortcoming of SOFCs that severely affects their reliability. Infrared thermography may provide a powerful tool for probing in situ SOFC electrode processes and the materials’ structural integrity, but, due to the typical design of pellet-type cells, a complete optical access to the electrode surface is usually prevented. In this paper, a specially designed SOFC is introduced, which allows temperature distribution to be measured over all the cathode area while still preserving the electrochemical performance of the device. Infrared images recorded under different working conditions are then processed by means of a dedicated image processing algorithm for quantitative data analysis. Results reported in the paper highlight the effectiveness of infrared thermal imaging in detecting the onset of cell failure during normal operation and in monitoring cathode activity when the cell is fed with different types of fuels.

Context:Cystic fibrosis-related diabetes (CFRD) is associated with worsening of inflammation and infections, and the beginning of insulin treatment is debated.Objectives:To verify high-mobility group box 1 protein (HMGB1) levels in CF patients according to glucose tolerance state, and analyze relationships with insulin secretion and resistance. To verify, in an in vitro model, whether HMGB1 gene expression and protein content were affected by insulin administration and whether these changes were dependent on CF transmembrane conductance regulator (CFTR) loss of function.Patients and Methods:Forty-three patients in stable clinical conditions and 35 age- and sex-matched controls were enrolled. Glucose tolerance was established in patients based on a 5 point oral glucose tolerance test (OGTT). Fasting glucose to insulin ratio (FGIR), HOMA-IR index, whole-body insulin sensitivity index (WIBISI), and the areas under the curve for glucose (AUCG) and insulin (AUCI) were calculated. HMGB1 was assayed in serum, in cell lysates and conditioned media using a specific ELISA kit. For the in vitro study we used CFBE41o− cells, homozygous for the F508del mutation, and 16HBE14o− as non-CF control. HMGB1 gene expression was studied by real-time RT-PCR. Cells were stimulated with insulin at 2.5 and 5 ng/mL. The CFTR inhibitor 172 and CFTR gene silencing were used to induce CFTR loss of function in 16HBE14o− cells.Results:HMGB1 levels were increased at onset of CFRD (5.04 ± 1.2 vs 2.7 ± 0.3 ng/mL in controls; P< .05) and correlated with FGIR (R = +0.43; P= .038), and AUCI (R = +0.43; P= .013). CFTR loss of function in the 16HBE14o− cells increased HMGB1 and was lowered by insulin.Conclusion:HMGB1 was increased in CF patients with deranging glucose metabolism and showed relationships with indexes of glucose metabolism. The increase in HMGB1 was related to CFTR loss of function, and insulin lowered HMGB1. Further research is required to verify whether HMGB1 could potentially be a candidate marker of onset of CFRD and to establish when to start insulin treatment.

The paper presents a method for mapping the temperature distribution of very fast transient events (i.e. having a bandwidth of 10 kHz or more) by means of a standard infrared camera working at 25 Hz frame rate with 320 × 256 pixels full frame. The proposed method is based on triggering multiple time-delayed acquisitions of the observed thermal phenomenon, which must be periodic, by means of a very precise and stable programmable digital micro-controller and by reconstructing the time domain IR sequence using the frames acquired at each trigger event. The measurement accuracy of the reconstruction process has been assessed by using a laser-cut planar resistor cyclically heated by means of a pulsed electrical current. A practical application to investigate the temperature distribution over the source metal of a power MOSFET device is finally presented.

We investigated how an extremely transposon element (TE)-rich organism such as the plant-symbiotic ascomycete truffle Tuber melanosporumexploits DNA methylation to cope with the more than 45,000 repeated elements that populate its genome. Whole-genome bisulfite sequencing performed on different developmental stages reveals a high fraction of methylated cytosines with a strong preference for CpG sites. The methylation pattern is highly similar among samples and selectively targets TEs rather than genes. A marked trend toward hypomethylation is observed for TEs located within a 1 kb distance from expressed genes, rather than segregated in TE-rich regions of the genome. Approximately 300 hypomethylated or unmethylated TEs are transcriptionally active, with higher expression levels in free-living mycelium compared to fruitbody. Indeed, multiple TE-enriched, copy number variant regions bearing a significant fraction of hypomethylated and expressed TEs are found almost exclusively in free-living mycelium. A reduction of DNA methylation, restricted to non-CpG sites and accompanied by an increase in TE expression, is observed upon treatment of free-living mycelia with 5-azacytidine. Evidence derived from analysis of the T. melanosporummethylome indicates that a non-exhaustive, partly reversible, methylation process operates in truffles. This allows for the existence of hypomethylated, transcriptionally active TEs that are associated with copy number variant regions of the genome. Non-exhaustive TE methylation may reflect a role of active TEs in promoting genome plasticity and the ability to adapt to sudden environmental changes.

This paper describes a rare occurrence of graphite in non-cratonic mantle rocks. Graphite has been found in garnet clinopyroxenite layers from the External Liguride peridotites that represent slices of subcontinental lithospheric mantle exhumed at the ocean floor in Mesozoic times. The high-pressure assemblage of the pyroxenites is characterized by garnet+Al–Na-rich clinopyroxene, and testifies to an early stage of equilibration at approximately 2.8 GPa and 1100 °C. Graphite occurs as small dispersed euhedral flakes and stacks of flakes. Structural characterization by microRaman spectrometry indicates a highly ordered structure, compatible with a high-temperature mantle origin. C isotope composition of graphite has a typical mantle signature. Fe–Ni–Cu sulphides occur as accessory phases, both as blebs enclosed in silicates (E-Type) and interstitial grains (I-Type). The sulphide assemblage (Ni-free pyrrhotite, pentlandite, Cu–Fe sulphides) mainly reflects subsolidus exsolution from high-temperature Fe–Ni–Cu monosulphide solid solutions with variable Ni (up to 18 wt%) and Cu content (up to 7 wt%). The origin of E- and I-Type sulphides requires the existence of an immiscible Fe–Ni–Cu sulphide liquid, which segregated from the partial melt of the garnet pyroxenite. Graphite precipitation in the pyroxenite was presumably related to the reduction of a more oxidized carbon species interacting with the sulphide liquid as a reducing agent.

Nitrogen assimilation by plant symbiotic fungi plays a central role in the mutualistic interaction established by these organisms, as well as in nitrogen flux in a variety of soils. In the present study, we report on the functional properties, structural organization and distinctive mode of regulation of TbNrt2 (Tuber borchii NRT2 family transporter), the nitrate transporter of the mycorrhizal ascomycete T. borchii. As revealed by experiments conducted in a nitrate-uptake-defective mutant of the yeast Hansenula polymorpha, TbNrt2 is a high-affinity transporter (Km=4.7 μM nitrate) that is bispecific for nitrate and nitrite. It is expressed in free-living mycelia and in mycorrhizae, where it preferentially accumulates in the plasma membrane of root-contacting hyphae. The TbNrt2 mRNA, which is transcribed from a single-copy gene clustered with the nitrate reductase gene in the T. borchii genome, was specifically up-regulated following transfer of mycelia to nitrate- (or nitrite)-containing medium. However, at variance with the strict nitrate-dependent induction commonly observed in other organisms, TbNrt2 was also up-regulated (at both the mRNA and the protein level) following transfer to a nitrogen-free medium. This unusual mode of regulation differs from that of the adjacent nitrate reductase gene, which was expressed at basal levels under nitrogen deprivation conditions and required nitrate for induction. The functional and expression properties, described in the present study, delineate TbNrt2 as a versatile transporter that may be especially suited to cope with the fluctuating (and often low) mineral nitrogen concentrations found in most natural, especially forest, soils.

cDNA arrays were used to explore mechanisms controlling fruiting body development in the truffle Tuber borchii. Differences in gene expression were higher between reproductive and vegetative stage than between two stages of fruiting body maturation. We suggest hypotheses about the importance of various physiological processes during the development of fruiting bodies.

ABSTRACTcDNA arrays were used to explore mechanisms controlling fruiting body development in the truffle Tuber borchii.Differences in gene expression were higher between reproductive and vegetative stage than between two stages of fruiting body maturation. We suggest hypotheses about the importance of various physiological processes during the development of fruiting bodies.

Summary Mutations and instability of mitochondrial DNA (mtDNA) are frequent in tumors but their pathogenic relevance is not established. To assess their role in the clinical management of malignant gliomas we have studied the D loop of mtDNA in 42 such tumors. Alterations were found in 36 of the cases. The MRI and the clinical follow-up of these patients suggest that these mutations are not associated with increased aggressiveness. mtDNA could be amplified from post-surgical tumor cavities in patients undergoing a loco-regional treatment. These results imply that mtDNA mutations are unlikely to play a role in diagnostic or prognostic evaluations of gliomas:their detection, however, could be of use for the clinical follow-up of malignant gliomas.

We describe the case of a 46-yr-old euthyroid woman, who was submitted to right lobectomy plus isthmusectomy because of a 30 mm large, rapidly growing thyroid nodule. Two cytological examinations of fine needle aspiration biopsy (FNAB) specimens were not diagnostic. Histology showed a neoplasm composed of nests of chief cells, almost completely replacing thyroid parenchyma, infiltrating the capsule and surgical resection margins, and invading perithyroid tissues. Immunohistochemical analysis revealed that the tumor stained positively to chromogranin, synaptophysin, NSE, S-100 protein and tyrosine hydroxylase, whereas no immunoreactivity was detected against cytokeratin, thyroglobulin, TTF-1, calcitonin and CEA. A diagnosis of thyroid paraganglioma (PG) was finally made. No complications developed following operation. Laboratory analysis and imaging study excluded multicentric disease, metastases to neck or extra-cervical organs, and multiple endocrine neoplasia (MEN). We report this unusual case, underscore its clinical and immunohistochemical features and discuss differential diagnosis.

Nitrogen retrieval and assimilation by symbiotic ectomycorrhizal fungi is thought to play a central role in the mutualistic interaction between these organisms and their plant hosts. Here we report on the molecular characterization of the key N-assimilation enzyme glutamine synthetase from the mycorrhizal ascomycete Tuber borchii (TbGS). TbGS displayed a strong positive co-operativity (n=1.7±0.29) and an unusually high S0.5 value (54±16 mM; S0.5 is the substrate concentration value at which v=½Vmax) for glutamate, and a correspondingly low sensitivity towards inhibition by the glutamate analogue herbicide phosphinothricin. The TbGS mRNA, which is encoded by a single-copy gene in the Tuber genome, was up-regulated in N-starved mycelia and returned to basal levels upon resupplementation of various forms of N, the most effective of which was nitrate. Both responses were accompanied by parallel variations of TbGS protein amount and glutamine synthetase activity, thus indicating that TbGS levels are primarily controlled at the pre-translational level. As revealed by a comparative analysis of the TbGS mRNA and of the mRNAs for the metabolically related enzymes glutamate dehydrogenase and glutamate synthase, TbGS is not only the sole messenger that positively responds to N starvation, but also the most abundant under N-limiting conditions. A similar, but even more discriminating expression pattern, with practically undetectable glutamate dehydrogenase mRNA levels, was observed in fruitbodies. The TbGS mRNA was also found to be expressed in symbiosis-engaged hyphae, with distinctively higher hybridization signals in hyphae that were penetrating among and within root cells.

The increasing frequency of nosocomial infections due to multi-resistant pathogens exerts a significant toll and calls for novel and better antibiotics. Different approaches can be used in the search for novel antibiotics acting on drug-resistant bacterial pathogens. We present some considerations on valid bacterial targets to be used for searching new antibiotics, and how the information from bacterial genome sequences can assist in choosing the appropriate targets. Other factors to be considered in target selection are the chemical diversity available for screening and its uniqueness. We will conclude discussing our strategy for searching novel antibacterials. This is based on a large collection of microbial extracts as a source of chemical diversity and on the use of specific targets essential for the viability of bacterial pathogens. Two assay strategies have been implemented: a pathway-based assay, where a series of essential bacterial targets is screened in a single assay; and a binding assay, where many targets can be screened individually in the same format.

Two familial Italian cases of Creutzfeldt-Jakob disease are reported. Clinical picture and life history are presented and compared: 1) with the findings in familial cases reported in other countries, 2) with the findings (age at onset, disease duration) in sporadic Italian cases.

A case of neuromuscular hyperactivity syndrome associated with a thymoma, high serum titres of anti-acetylcholine receptor and anti-DNA antibodies is reported. The study of peripheral nerve conduction revealed a peripheral neuropathy. Repetitive stimulation showed a decrease in the fifth M response. Myasthenic symptoms were anamnestically reported but were absent at clinical observation. The clinical picture and EMG examination improved after phenytoin administration.