Serum copper and zinc in industrial centers in Slovakia

The association between serum copper and zinc concentrations and age, sex, and other risk factors of cardiovascular disease in randomly selected adult volunteers aged 19–59 were investigated. There was a positive relationship between copper and age in both sexes, but zinc was negatively correlated with age in males only. Serum zinc was positively related to HDL-cholesterol in males. Serum copper was positively related to total cholesterol and LDL-cholesterol but negatively correlated to HDL-cholesterol in males. A positive relationship to body mass index was observed in females only. Subjects have been divided into a control group and a group with marked risk factors of cardiovascular disease. The levels of zinc were not different, whereas the levels of copper in both males and females were significantly higher in the risk group. Our results suggested a positive relationship between serum copper and cumulation of more factors of cardiovascular disease, however, their causal effect in humans has to be investigated further.     

Peripheral and central 5-hydroxytryptamine in trisomy 21.

Peripheral and central metabolism of 5-hydroxytryptamine was studied in 16 patients with trisomy 21 and compared to that in 4 karyotypically normal mentally retarded children. Serum 5-hydroxytryptamine was markedly decreased in the trisomics whereas cerebrospinal fluid levels of 5-hydroxytryptamine and 5-hydroxyindole acetic acid were increased in the same groups. These results are discussed with respect to regulatory mechanisms of 5-HT metabolism.     

Partial trisomy 4 resulting from a complex maternal rearrangement of chromosomes 2, 4, and 18 with interstitial translocation

Summary A woman presented a complex chromosome rearrangement with translocation between chromosome 2 and 4 in addition to an insertion of the band 4q12q13 in the long arm of chromosome 18. The authors present a case study of the daughter who displayed the abnormal chromosome 18 and trisomy of band 4q12q13.     

Nitrate reductase,nitrite reductase and glutamate dehydrogenase levels in roots and leaves of maize seedlings

Total activities of nitrate and nitrite reductases were higher in 4 to 20 day old maize plants in the leaves than in the roots. The ratio of activities found in the leaves and in the roots respectively was much higher in the case of nitrate reductase than in the case of nitrite reductase. On the other hand higher glutamate dehydrogenase activity in the roots than in the leaves clearly indicates that the roots play a more important role in the assimilation of ammonium than in the assimilation of nitrate. When comparing the distribution of seminal and nodal adventitious roots of maize seedlings with the assimilation of inorganic nitrogen on the basis of enzyme levels, it could be deduced that during the first 20 days of seedling growth seminal roots were more involved in the assimilation of nitrate whereas nodal adventitious roots were more active in ammonium assimilation.     

An evaluation of three pesticides: Piritione,supercypermethrin and metolachlor in transformation bioassays of BHK21 and hamster embryo cells

In a study of potential carcinogenicity of pesticides, Piritione, metolachlor (in the form of Dual and VUCHT 524) and Supercypermethrin (in the form of Supercypermethrin EC and Supercypermethrin TP) were assayed for induction of anchorage independent growth of BHK21 cells and morphological transformation of Syrian hamster embryo cells. The activity of these substances in both transformation assays was compared to the activity of the direct-acting ultimate carcinogen N-methyl-N-nitrosourea. In comparison to the very strong transforming activity of N-methyl-N-nitrosourea all pesticides tested with or without S9 fraction manifested a very weak, weak, medium or strong effect. The ability to induce anchorage independent growth was graded as follows: Dual < Supercypermethrin EC < Supercypermethrin TP Piritione < VUCHT 524. Results of Syrian hamster embryo cell transformation assay were very similar to the BKH21 transformation assay. VUCHT 524 strongly induced transformation whereas Dual was inactive. Piritione and Supercypermethrin EC and Supercypermethrin TP elicited a slight but significant positive response.     

Bacteria can be selected to help beneficial plasmids spread

A recent commentary raised concerns about aspects of the model and assumptions used in a previous study which demonstrated that selection can favor chromosomal alleles that confer higher plasmid donation rates. Here, the authors of that previous study respond to the concerns raised.

In our original work [1], we demonstrated experimentally that selection can favor chromosomal alleles that confer higher plasmid donation rates, given the plasmid is beneficial and the recipient has an elevated chance of carrying the donor allele (i.e., preferential donation to kin). Our experiments demonstrated this effect via 2 mechanisms of preferential donation: biased conjugation rates and structured populations. We interpreted these results through the lens of kin selection theory (benefits via horizontal gene transfer to kin), supported by simulations and an analytical fitness function model. These results hold importance by outlining that the evolution of plasmid transfer rates (a key aspect of the antibiotic resistance crisis) is not necessarily the sole product of selection on the plasmid itself and forms part of a broader series of papers from our labs investigating the sociomicrobiology of plasmids [2–4].A new commentary raises concerns over our fitness function model, flagging issues with both the structure of the model and assumptions made in our analysis [5]. We stand by the general conclusions of our work but accept that our fitness function and stated analysis assumptions could be better formulated. Our initial fitness function is heuristic in the sense it was designed to capture general processes acting on the fitness of individuals, dependent on the plasmid and donor allele status—without explicitly modeling the myriad demographic events of dispersal, reproduction, conjugation, and death that result in selective shifts across a metapopulation of cells. Specifically, we captured the “force of infection” faced by an uninfected cell as the product of average plasmid prevalence and average donor allele prevalence in the local patch (p_jq_j; see commentary for notation details). We agree with the authors that this force of infection is better phrased as the average of the product ((1/N)∑p_ij q_ij), in part because this avoids the potential pathology under limit conditions described by the authors, but also because this approach better highlights that the particular social trait in question is an “other only” cooperative trait [6], illustrated by commentary equation [2], where transmission to self and transmission to others are separated. This separation has the important consequence of highlighting that unlike many microbial social traits where benefits accrue to a group (including self), a cooperative plasmid donor trait can only benefit other cells that lack the plasmid. Given established costs of donation (e.g., see figure S2 in our original article), this defines our “donor” behavior as an altruistic trait, which can, therefore, only be favored by selection given nonrandom interactions among individuals (e.g., [7]).Our experimental results outline 2 mechanisms of nonrandom interactions: preferential donation to kin and population structure. Each of these mechanisms will generate positive covariances between focal individual q_ij and non-self-recipient q_j donor allele states (cov(q_j, q_ij) > 0). The pathway via preferential donation to kin (order-of-magnitude differences according to our analyses and more recent measurements among lineages coexisting within natural populations [8]) will also likely generate positive covariances between donor and recipient abilities (cov(s_ij, q_ij) > 0). In contrast, to arrive at the result that selection always works against plasmid donor alleles (equation [4]), the commentary makes the assumption that both of the above covariances are zero. We suggest that the additional analyses begun by the authors are an exciting starting point to better map selection on donor alleles, under a broader array of defined assumptions on cell–cell and gene–gene structure, ideally informed by data on structures found in natural bacterial populations.     

Diversity,taxonomy, and evolution of archaeal viruses of the class Caudoviricetes

The archaeal tailed viruses (arTV), evolutionarily related to tailed double-stranded DNA (dsDNA) bacteriophages of the class Caudoviricetes, represent the most common isolates infecting halophilic archaea. Only a handful of these viruses have been genomically characterized, limiting our appreciation of their ecological impacts and evolution. Here, we present 37 new genomes of haloarchaeal tailed virus isolates, more than doubling the current number of sequenced arTVs. Analysis of all 63 available complete genomes of arTVs, which we propose to classify into 14 new families and 3 orders, suggests ancient divergence of archaeal and bacterial tailed viruses and points to an extensive sharing of genes involved in DNA metabolism and counterdefense mechanisms, illuminating common strategies of virus–host interactions with tailed bacteriophages. Coupling of the comparative genomics with the host range analysis on a broad panel of haloarchaeal species uncovered 4 distinct groups of viral tail fiber adhesins controlling the host range expansion. The survey of metagenomes using viral hallmark genes suggests that the global architecture of the arTV community is shaped through recurrent transfers between different biomes, including hypersaline, marine, and anoxic environments.

Comparative genomics and host range analysis reveals the remarkable diversity and evolution of tailed archaeal viruses of the order Caudoviricetes, which together with their bacterial relatives arguably represent the most abundant and widespread virus group on our planet.     

Qualitative and quantitative analysis of the secondary structure of cytochrome C Langmuir-Blodgett films

A qualitative and quantitative analysis of the conformation of Langmuir-Blodgett (LB) dried films of cytochrome C on silicon wafers was performed by Fourier transform ir (FTIR) spectroscopy. A deconvolution procedure was applied to the amide I band analysis, in order to determine the percentage of the different secondary structures. Qualitative analysis was performed by examining difference spectra. Films obtained by spreading protein solutions at pH 7.4 and 1, dried at 25 and 100°C, on silicon wafers were also examined in order to detect spectral components associated with denatured protein domains, and to compare them with cytochrome C LB films. FTIR spectroscopy showed that the following important changes characterise LB film spectra: (a) the α-helix component is higher (its percentage is 57 and 54%) than the one estimated in dried film obtained by spreading the solutions at pH 7.4 on a silicon substrate (43%), (b) there is an increase in the intensity of bands attributed to protonated carboxy group bands, involved and not involved in the formation of hydrogen bonds, and a decrease in those attributed to deprotonated carboxy groups, (c) the intensity of several bands attributed to aromatic amino acids and aliphatic chains increases, and (d) bands due to O(SINGLEBOND)H stretching vibrations of crystallization water are present. These conformational changes could be induced by protein-protein interaction caused by the close packing of molecules that occurs during LB film formation; it cannot be excluded that they may be accompanied by partial changes in the tertiary structure of the protein. A preferential orientation of protein molecules in LB films is also a possibility. © 1997 John Wiley & Sons, Inc. Biopoly 42: 227–237, 1997     

Formation of N-Pyroglutamyl Peptides from N-Glu and N-Gln Precursors in Aplysia Neurons

Abstract : Matrix-assisted laser desorption/ionization with time-of-flight mass spectrometry is used to examine the formation of N -pyroglutamate (pGlu) in single, identified neurons from Aplysia . Six pGlu peptides are identified in the R3-14 and the R15 neurons that result from in vivo processing of peptides containing either Glu or Gln at their respective N-termini. Moreover, we show that Glu-derived pGlu is not a sample collection or measurement artifact. The pGlu peptides are detected in isolated cell bodies, regenerated neurites in culture, interganglionic connective nerves, cell homogenates, and collected releasates. We also demonstrate that R3-14 cells readily convert a synthetic N -Glu peptide to its pGlu analogue, indicating the presence of novel enzymatic activity.