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Hyperhomocysteinemia (Hcy) is an independent factor of cardiovascular disease, which is the main cause of morbidity and mortality both in uremic and kidney transplant patients. The aim of the study was to determine Hcy, plasminogen activator inhibitor (PAI-1) and lipoprotein (a) (Lp(a)) serum levels in 70 patients with a well functioning renal transplant. We also verified whether these levels were modified by a multivitamin therapy. The genetic polymorphism of the methylenetetrahydrofolate reductase (MTHFR) enzyme which plays a main role in Hcy metabolism, was studied as well. We found Hcy, PAI-1 and Lp(a) levels significantly elevated with respect to healthy control subjects. The thermolabile form of the MTHFR enzyme was linked to higher Hcy levels. After a short time on therapy with B6, B12 and folic acid vitamins, Hcy and PAI-1 decreased to normal levels. The authors conclude that high Hcy levels could be a relevant covariate for cardiovascular disease in transplant patients and they suggest that vitamin supplementation be recommended as a part of therapy.

The serum copper parameters were evaluated in 41 male trained runners and in a control group of 24 male subjects engaged in normal physical activity. In the runner group lower serum copper concentrations, lower serum ceruloplasmin biological activity, and higher serum ceruloplasmin levels were found compared with the control group. Reduced serum copper levels may affect the ceruloplasmin biological activity, even if the serum ceruloplasmin levels are higher. The results suggest that more attention should be paid to serum copper and ceruloplasmin in athletes.

Hyperhomocysteinemia is a well established risk factor for atherothrombotic disease, and the request for homocysteine determinations and the number of laboratories that need to perform this assay to assess individual risk profile is increasing. Different methods to evaluate homocysteine plasma levels are at present available. In the present study three methods, an in-house high-pressure liquid chromatographic (HPLC) method (considered as reference method) and two commercial immunoassays, an enzyme-linked immunoassay (EIA) and an automated fluorescence polarization immunoassay (FPIA), were used to measure homocysteine plasma levels in 100 samples. The median of homocysteine plasma levels obtained by HPLC was 9.0 micromol/L (range 4.2-23.0); the median of values obtained by EIA and FPIA were 10.6 micromol/L (range 3.3-21.5) and 9.6 micromol/L (4.8-20.2), respectively. The FPIA method showed the lowest within-run and between-run coefficients of variation (3.6% and 4.1%, respectively). There was a significant correlation between EIA and HPLC (r=0.81; p0.0001), and between FPIA and HPLC (r=0.85; p0.0001). The Bland-Altman analysis showed that FPIA agreed best with HPLC; EIA displayed a relatively wide scatter of difference data points. The present results indicate that the technological characteristics of the FPIA assay make this method suitable for the determination of Hcy in clinical laboratories.

Rhodococcus sp. strain BCP1 (DSM 44980) co-metabolizes chlorinated compounds and mineralizes a broad range of alkanes being highly tolerant to these toxic chemicals. Here, we present the high-quality draft genome sequence of strain BCP1 consisting of 6,231,823 bp, with a G+C content of 70.4%, 5,902 protein-coding genes, and 58 RNAs genes. Rhodococcus genus comprises Gram-positive, non-sporulating, aerobic bacteria that are widely distributed in the environment (1). Rhodococcus sp. strain BCP1 (formerly: Rhodococcus aetherovorans strain BCP1, DSM 44980) was selected from an aerobic butane-utilizing consortium as the prevailing isolate able to co-metabolize chloroform, vinyl chloride and trichloroethylene (2, 3). As BCP1 also catabolizes a wide range of aliphatic, alicyclic and carboxylated alkanes, it represents a strain of considerable environmental and industrial interest (4). The genome sequencing of Rhodococcus sp. BCP1 was performed using 454 sequencing technology (Roche GS FLX Titanium). The total number of sequence reads were 668,686 from one shotgun library and 353,744 from one paired-end library (8-kb inserts). All the reads were assembled using Newbler 2.6 into 123 contigs with an N50 length of 237,787 bp and an average genome coverage of 65x. Based on paired-end directional information, the contigs were further ordered into 3 scaffolds, giving a total genome size of 6.2 Mb with a G+C content of 70.4%.

Staphylococcus aureus is the major causative agent of skin and soft tissue infections, whose prevention and treatment have become more difficult due to the emergence of antibiotic-resistant strains. In this regard, the development of an effective treatment represents a challenge that can be overcome by delivering new antibiofilm agents with appropriate nanocarriers. In this study, a biosurfactant (BS) isolated from Lactobacillus gasseri BC9 and subsequently loaded in liposomes (LP), was evaluated for its ability to prevent the development and to eradicate the biofilm of different methicillin resistant S. aureus (MRSA) strains. BS from L. gasseri BC9 was not cytotoxic and was able to prevent formation and to eradicate the biofilm of different MRSA strains. BS loaded liposomes (BS-LP) presented a mean diameter (lower than 200 nm) suitable for topical administration and a low polydispersity index (lower than 0.2) that were maintained over time for up 28 days. Notably, BS-LP showed higher ability than free BS to inhibit S. aureus biofilm formation and eradication. BS-LP were loaded in lyophilized matrices able to quickly dissolve (dissolution time lower than 5 s) upon contact with exudate, thus allowing vesicle reconstitution. In conclusion, in this work, we demonstrated the antibiofilm activity of Lactobacillus-derived BS and BS-LP against clinically relevant MRSA strains. Furthermore, the affordable production of lyophilized matrices containing BS-LP for local prevention of cutaneous infections was established.

The outbreak of SARS-CoV-2 pandemic highlighted the worldwide lack of surgical masks and personal protective equipment, which represent the main defense available against respiratory diseases as COVID-19. At the time, masks shortage was dramatic in Italy, the first European country seriously hit by the pandemic: aiming to address the emergency and to support the Italian industrial reconversion to the production of surgical masks, a multidisciplinary team of the University of Bologna organized a laboratory to test surgical masks according to European regulations. The group, driven by the expertise of chemical engineers, microbiologists, and occupational physicians, set-up the test lines to perform all the functional tests required. The laboratory started its activity on late March 2020, and as of the end of December of the same year 435 surgical mask prototypes were tested, with only 42 masks compliant to the European standard. From the analysis of the materials used, as well as of the production methods, it was found that a compliant surgical mask is most likely composed of three layers, a central meltblown filtration layer and two external spunbond comfort layers. An increase in the material thickness (grammage), or in the number of layers, does not improve the filtration efficiency, but leads to poor breathability, indicating that filtration depends not only on pure size exclusion, but other mechanisms are taking place (driven by electrostatic charge). The study critically reviewed the European standard procedures, identifying the weak aspects; among the others, the control of aerosol droplet size during the bacterial filtration test results to be crucial, since it can change the classification of a mask when its performance lies near to the limiting values of 95 or 98%.

In an aquifer-aquitard system in the subsoil of the city of Ferrara (Emilia-Romagna region, northern Italy) highly contaminated with chlorinated aliphatic toxic organics such as trichloroethylene (TCE) and tetrachloroethylene (PCE), a strong microbial-dependent dechlorination activity takes place during migration of contaminants through shallow organic-rich layers with peat intercalations. The in situ microbial degradation of chlorinated ethenes, formerly inferredby the utilization of contaminant concentration profiles and Compound-Specific Isotope Analysis (CSIA), was here assessed using Illumina sequencing of V4 hypervariable region of 16S rRNA gene and by clone library analysis of dehalogenase metabolic genes. Taxon-specific investigation of the microbial communities catalyzing the chlorination process revealed the presence of not only dehalogenating genera such as Dehalococcoides and Dehalobacter but also of numerous other groups of non-dehalogenating bacteria and archaea thriving on diverse metabolisms such as hydrolysis and fermentation of complex organic matter, acidogenesis, acetogenesis, and methanogenesis, which can indirectly support the reductive dechlorination process. Besides, the diversity of genes encoding some reductive dehalogenases was also analyzed. Geochemical and 16S rRNA and RDH gene analyses, as a whole, provided insights into the microbial community complexity and the distribution of potential dechlorinators. Based on the data obtained, a possible network of metabolic interactions has been hypothesized to obtain an effective reductive dechlorination process.

The reactions between [Fe 6 C(CO) 16 ] 2− and CuCl, in refluxing THF, yield [Fe 5 C(CO) 14 (CuCl)] 2− ( 1 ), [Fe 4 C(CO) 12 (CuCl) 2 ] 2− ( 2 ), or [{Fe 4 Cu 2 C(CO) 12 (μ-Cl)} 2 ] 2− ( 3 ), depending on the Fe 6 /CuCl ratio. The chloro ligands of these clusters can be displaced either spontaneously, or by metal-assisted substitution, to give the bromo derivative [Fe 5 C(CO) 14 (CuBr)] 2− ( 4 ) or the solvento complexes [Fe 5 C(CO) 14 (CuTHF)] − ( 5 ) and [Fe 4 C(CO) 12 (CuNCMe) 2 ] ( 6 ). The latter can be also obtained directly, by metal substitution from [Fe 6 C(CO) 16 ] 2− and [Cu(NCMe) 4 ]BF 4 , or by polyhedral expansion from [Fe 4 C(CO) 12 ] 2− . All the clusters are octahedral, with the copper atoms in a pseudo-linear geometry, where one of the coordination positions is occupied by the interstitial carbide. The two copper atoms in the Fe 4 Cu 2 clusters are always in cis geometry and, in the dimer [{Fe 4 Cu 2 C(CO) 12 (μ-Cl)} 2 ] 2− , they are joined through chlorides. The role of the different metal centres in determining the redox activity of the heteronuclear Fe–Cu clusters 1 , 2 , 3 , has been studied by electrochemical methods. In the bridged dimer 3 , the two Fe 4 Cu 2 C cluster units resulted electronically not communicating.

Polychlorinated biphenyls (PCBs) are ubiquitous persistent organic pollutants that can be co-metabolically biotransformed by biphenyl-utilizing bacteria. In this study, terminal-restriction fragment length polymorphism (T-RFLP) was applied to the substrate specificity-determining region of the 2,3-biphenyl dioxygenase encoding genes of a microbial community found in a PCB-polluted soil. Notably, both the total biphenyl/PCB-utilizing community and its members actively expressing the 2,3-biphenyl dioxygenase gene were analyzed. T-RFLP fingerprinting along with gene library construction allowed us not only to detect biphenyl dioxygenases related to the well characterized catabolic patterns of Pseudomonas pseudoalcaligenes KF707 and Burkholderia xenovorans LB400, but also to reveal novel environmental enzyme classes displaying amino acid substitutions that may be related to broader specificity and improved catalytic properties. Furthermore, space and time of sampling along with bioavailability conditions of different PCBs were considered possible sources of profile variability.

Tellurite (TeO3(2-)) is the most toxic and soluble oxyanion among tellurium (Te) compounds. The effects of the metalloid anion on the oxidative stress response of the obligate aerobe Pseudomonas pseudoalcaligenes KF707 were investigated. Cells treated with sub-lethal concentrations of TeO3(2-) showed neither adaptation to it nor cross-protection against oxidants such as 1,1'-4,4'-bipyridinium dichloride (paraquat, PQ2+), diazenedicarboxylic acid bis-N,N-dimethylamide (diamide), tert-butyl hydroperoxide (tBH) and hydrogen peroxide (H2O2). Notably, TeO3(2-) exerted a synergic effect on the toxicity of these latter oxidants. Tellurite was shown to decrease the cellular content of reduced thiols (RSH) with a consequent increase in the production of reactive oxygen species (ROS) and stimulation of the superoxide dismutase (SOD) activity. However, since the time course of ROS production by TeO3(2) (t1/2 > 30 min) was much slower than that with PQ2+ and/or diamide (t1/2

The susceptibility to various biocides was examined in planktonic cells and biofilms of the obligate aerobe, PCBs degrader, Pseudomonas pseudoalcaligenes KF707. The toxicity of two antibiotics, amikacin and rifampicin, three metalloid oxyanions (AsO2 −, SeO3 2−, TeO3 2−) and three metal cations (Cd2+, Ni2+, Al3+) was tested at two stages of the biofilm-development (4 and 24 h) and compared to planktonic cells susceptibility. Mature biofilms formed in rich (LB, Luria–Bertani) medium were thicker (23 μm) than biofilms grown in minimal (SA saccarose-arginine) medium (13 μm). Early grown (4 h) SA-biofilms, which consisted of a few sparse/attached cells, were 50–100 times more resistant to antibiotics than planktonic cells. Conversely, minor changes in tolerance to metal(loid)s were seen in both SA- and LB-grown biofilms. In contrast to planktonic cells, no reduction of TeO3 2− to elemental Te(0) or SeO3 2− to elemental Se(0) was seen in KF707 biofilms. The data indicate that: (a) metal tolerance in KF707 biofilms, under the growth and exposure conditions described here, is different than antibiotic tolerance; (b) KF707 planktonic cells and biofilms, are almost equally susceptible to killing by metal cations and oxyanions, and (c) biofilm-tolerance to TeO3 2− and SeO3 2− is not linked to metalloid reduction; this means that KF707 planktonic cells and biofilms differ in their physiology and strategy to counteract metalloid toxicity.

This study shows that the oxyanion tellurite TeO32- can be used as a tool to detect and quantify the release in soil microcosms of Pseudomonas pseudoalcaligenes KF707, a strain spontaneously resistant to tellurite with a minimal inhibitory concentration (MIC) of 150 μg ml-1. KF707 cells which carry the genes for degradation of a wide range of polychlorinated biphenyl congeners (PCBs) were used for inoculation of laboratory microcosms prepared with two different PCB-contaminated soils (Ci/s and Di/s) in the presence or absence of biphenyl as carbon source. In all microcosms supplemented with biphenyl, significant survival of strain KF707 was noted over a time period of 35 days; conversely, in microcosms containing Ci/s soil without biphenyl addition a rapid decrease in KF707 inoculated cells was observed. By comparing the number of inoculated KF707 cells with the number of indigenous bacteria growing on biphenyl (IBGB) of both Ci/s and Di/s microcosms, it could be concluded that the KF707/IBGB ratio is a relevant parameter in determining the fate of the added strain. The efficacy of potassium tellurite as a selective marker to monitor strain KF707 in laboratory microcosms was confirmed by ARDRA analyses of the 16S rDNA, while the isolated indigenous bacteria growing on biphenyl were identified as members of three different species of the genus Pseudomonas. We also report that in microcosms inoculated with KF707 cells in the absence of biphenyl, only low chlorinated biphenyls were degraded. © 2002 Éditions scientifiques et médicales Elsevier SAS. All rights reserved.