Reduction of SARS-CoV-2 viral load in exhaled air by antiseptic chewing gum: a pilot trial.

PURPOSE: The dominant route of transmission of SARS-CoV-2 is airborne, through respiratory transmission by aerosols or droplets which can be measured by viral load in exhaled air. Several natural substances have shown antiviral activity. The aim of this pilot study was to investigate the effect of a chewing gum containing natural antiseptic ingredients (cinnamon-, peppermint- and lemon-oil, quercetin, spermidine, ginger and ginseng) on viral load in exhalative air in patients infected with SARS-CoV-2. METHODS: Nine patients infected with SARS-CoV-2 were enrolled and exhaled forcefully into a special mouthpiece at different time points before and after chewing the antiseptic gum. The mouthpiece contained a filter paper serving for extraction of coronaviruses following real-time PCR to quantify the viral load. RESULTS AND CONCLUSION: Cycle threshold (Ct) values of all patients increased after chewing the gum. The mean difference between the Ct values at baseline (before chewing the antiseptic gum) and time point 30 min (15 min after chewing) was 3.8 ± 2.6; (93% viral load reduction; p = 0.002). Time point 15 min (2.7 ± 1.7 (83% viral load reduction; p = 0.003)), 60 min (3.0 ± 3.4 (88% viral load reduction; p = 0.028)), 90 min (3.7 ± 1.8 (92% viral load reduction; p = 0.004)) and 120 min (3.0 ± 3.7 (91% viral load reduction; p = 0.05)) showed similar results. The antiseptic chewing gum demonstrated a significant potential to reduce SARS-CoV-2 viral load in exhalative air and, in this way, reduce further spread and infection risk. Larger placebo-controlled clinical trials are required to confirm these findings further.

Term and preterm labour are associated with distinct microbial community structures in placental membranes which are independent of mode of delivery.

Infection is considered a possible trigger for preterm labour, supported by evidence showing the presence of bacteria in the placenta and placental membranes from preterm births. In this study, 16S rDNA pyrosequencing was used to identify bacteria in placental membranes. Caesarean sections and vaginal deliveries at term were found to harbour common genera. Mycoplasma hominis, Aerococcus christensenii, Gardnerella vaginalis and Fusobacterium nucleatum were either only present in preterm membranes or in greater abundance than at term. These data support previous studies that used either targeted qPCR or broad-range 16S rDNA PCR and cloning but not a recent microbiome analysis of placental tissue using high-throughput sequencing.

Selenium in blood, semen, seminal plasma and spermatozoa of stallions and its relationship to sperm quality.

The essential trace element selenium is indispensable for male fertility in mammals. Until now, little data existed regarding the relationship between selenium and sperm quality in the stallion. Selenium, or selenium-dependent glutathione peroxidase activity, was determined in red blood cells, semen, seminal plasma and spermatozoa, and the percentages of spermatozoa with progressive motility (PMS), intact membranes (PMI), altered (positive) acrosomal status (PAS) and detectable DNA damage, determined by the sperm chromatin structure assay, were evaluated in 41 healthy stallions (three samples each). The pregnancy rate per oestrus cycle (PRC) served as an estimation of fertility. An adverse effect on stallion fertility caused by low dietary selenium intake was excluded, as all stallions had sufficient selenium levels in their blood. Interestingly, no significant correlations (P > 0.05) between the selenium level in blood and the selenium level in seminal plasma or spermatozoa were found, suggesting that the selenium level in blood is no indicator of an adequate selenium supply for spermatogenesis. The selenium level in spermatozoa (nmol billion(-1)) was correlated with PMI, PMS and PAS (r = 0.40, r = 0.31 and r = -0.42, respectively; P

Metal-containing proteins in the apoptosis and redox processes in the rat prostate and human prostate cells.

Several trace elements, such as Se, Cu, Mn, and Zn are bound to proteins (metallo- and metalloidproteins) in the prostate gland. Currently, it is known that some of those elements play a role in the apoptosis of different cells and redox processes. For the detection of such proteins, analytical and biochemical procedures were combined. SEC and ICP-MS were used to detect some trace elements, which are bound to proteins in the prostate cytosol and/or in the human prostate cell lines. Several antibodies against specific proteins were tested. By means of some of these antibodies several trace element-containing proteins, such as selenoproteins and Cu- and Cu-Zn-proteins, could be identified in the prostate. In addition, the localization of such metal- and metalloid-containing proteins in the micro organelles and cytosol of the prostate indicates specific functions of these proteins because, as it is known, such metal- and metalloid proteins play a role in the apoptosis and especially in the redox processes.

Effect of a swim training on homocysteine and cysteine levels in rats.

The purpose of this study was to investigate the effects of a 8-week of swim training on total plasma homocysteine and cysteine levels in 16 male Sprague-Dawley rats aged 17 weeks. We also evaluated the activity of hepatic cystathionine beta-synthase (CBS), an enzyme involved in the metabolism of Hcy, the concentration of plasma glutathione, taurine, and a fraction of vitamin B6: the pyridoxal 5-phosphate (PLP). After one week of acclimatization, rats were randomly divided into two groups: 8 non-trained (NTR) and 8 trained rats (TR). Following the training period, body weight gain was lower in TR than in NTR. Plasma homocysteine did not differ among groups while significantly lower plasma cysteine and taurine levels were found in TR (157.83 +/- 8.6 micromol/L; 133.01 +/- 9.32 micromol/L; P < 0.05) compared with data of NTR (176.19 +/- 4.9 micromol/L; 162.57 +/- 8.16 micromol/L; P < 0.05). No significant changes in hepatic CBS activity were observed in TR compared with NTR. Moreover, values for plasma glutathione and PLP concentrations were not affected by training.These results indicate that training reduces plasma cysteine and taurine levels whereas it does not modify other studied parameters. Thus, physical training may regulate cysteine metabolism.

Intake, ingesta retention, particle size distribution and digestibility in the hippopotamidae.

Although several aspects of the digestive physiology of the hippopotamidae-non-ruminating foregut fermenters-have been described, ingesta kinetics and passage characteristics of these species are not well understood. The most outstanding feature of the hippo digestive physiology reported so far is the very long mean ingesta retention times (MRTs) measured by Foose [Foose, T., 1982. Trophic strategies of ruminant versus nonruminant ungulates. PhD dissertation, University of Chicago, Chicago.]. Since those data had been investigated with animals without water access, we intended to measure MRT in hippos which were allowed to enter water pools during the night. MRT parameters as well as dry matter (DM) digestibility were determined in four common (Hippopotamus amphibius) and four pygmy hippos (Hexaprotodon liberiensis) on two different diets each using cobalt ethylendiamintetraacetate (Co-EDTA) as a fluid, chromium (Cr)-mordanted fibre (<2 mm) as a particle and acid detergent lignin (ADL) as an internal digestibility marker. Four of the animals additionally received cerium (Ce)-mordanted fibres (2-10 mm) as particle markers. Total MRTs for fluids and particles ranged between 20-35 and 48-106 h in the common and between 13-39 and 32-107 h in the pygmy hippos. The difference between fluid and particle retention was greater than usually reported in ruminants. Excretion patterns of the markers differed from those usually observed in ruminants but resembled those reported for macropods (kangaroos), indicating a plug-flow reactor-like physiology in the hippo forestomach (FRST). This finding complements other described similarities between the macropod and the hippo forestomach. The measurements of larger particle retention profiles suggest that in the hippo, larger particles might be excreted either faster or at the same rate as smaller particles, indicating a general difference between ruminants and hippos with respect to differential particle retention. The digestive physiology of hippos is characterised by a generally low food intake, long ingesta retention times and dry matter digestibilities lower than reported in ruminants. Moderate digestibilities in spite of long retention times might be the result of the generally high average ingesta particle size in hippos. The comparatively easy management of pygmy hippos, together with the significant correlations between food intake, MRT and digestibility in the pygmy hippos of this study, recommends this species for further studies on the interplay of these parameters in herbivore digestive physiology.

Elemental contents in Napoleon's hair cut before and after his death: did Napoleon die of arsenic poisoning?

Whether or not Napoleon died of arsenic poisoning is an open question on which debate has been active since 1960. This work examined several of his hairs, cut at different times and in different places: two pieces cut the day after his death on the island of St. Helena (1821) and two pieces cut seven years earlier (1814) during his first exile on the island of Elba. INAA results show that all of the samples of Napoleon's hair have an elevated arsenic concentration. These results disfavor the arsenic poisoning theory. Aside from arsenic, 18 other elements are reported, providing additional information for examining the arsenic poisoning theory.

Revised superconducting phase diagram of hole-doped Na(x)(H3O)(z)CoO2 x yH(2)O.

We have studied the superconducting phase diagram of NaxCoO2.yH(2)O as a function of electronic doping, characterizing our samples both in terms of Na content x and the Co valence state. Our findings are consistent with a recent report that intercalation of H3O+ ions into NaxCoO2, together with water, acts as an additional dopant, indicating that Na substoichiometry alone does not control the electronic doping of these materials. We find a superconducting phase diagram where optimal T(C) is achieved through a Co valence range of 3.24-3.35, while T(C) decreases for materials with a higher Co valence. The critical role of dimensionality in achieving superconductivity is highlighted by similarly doped nonsuperconducting anhydrous samples, differing from the superconducting hydrate only in interlayer spacing.

Determination of the beta- branching ratio of 64Cu by mass spectrometric investigations of the decay products in neutron transmuted copper.

The beta- branching ratio of 64Cu was determined by investigating the resulting decay products in copper doped by neutron transmutation. The numbers of 64Zn and 64Ni atoms were analyzed using isotope dilution analysis combined with thermal ionization mass spectrometry. A beta- branching ratio of (38.06+/-0.30)% was obtained, which agrees with the study of Kawada (Appl. Radiat. Isot. 37 (1) (1986) 7) to a higher accuracy. However, our result differs from the value cited in the NUDAT database of (39.0+/-0.3)%.

Association between Kaposi's sarcoma and atherosclerosis: implications for gammaherpesviruses and vascular disease.

The treatment of HIV-positive patients with protease inhibitors has been suggested to increase their risk of atherosclerosis. The cause of this accelerated atherogenesis is unknown, but on the basis of previous studies we postulated that it could be linked to the presence of human herpesvirus-8. A retrospective analysis of post-mortem reports showed a strong correlation between Kaposi's sarcoma and the presence of atheroma. This hypothesis merits further investigation.

Characterization of neutron transmuted zinc traces in pure copper materials by isotope dilution mass spectrometry.

The neutron transmutation doping (NTD) of highly pure copper with zinc was investigated as a promising means of achieving controlled gradation of the zinc content in the range 1-20 microg g(-1). The doping process leads to the enrichment of two stable isotopes 64Zn and 66Zn in a ratio which differs from that of natural isotopic distribution. Mass spectrometric investigations by thermal ionization mass spectrometry (TIMS) were performed to validate the results obtained by gamma spectrometry. The investigations included both determination of the isotopic ratios of the doped zinc isotopes and the analysis of the accumulated zinc contents by isotope dilution (ID) analysis. Thereby a sample-specific correction of the blank could be performed because the isotope 68Zn was not influenced, because of the transmutation process. The results obtained by TIMS prove the strict proportionality of the doped zinc content, in the range 5 to 20 microg g(-1), to the neutron fluence. Comparison with gamma spectrometric results showed a very good agreement within the uncertainties.

Genetic diversity of Neisseria lactamica strains from epidemiologically defined carriers.

We assessed the genetic diversity of 26 Neisseria lactamica strains from epidemiologically related sources, i.e., groups of kindergartens and primary schools in three Bavarian towns, by the partial sequencing of the argF, rho, recA, and 16S ribosomal genes. We found a total of 17 genotypes, of which 12 were found only in one strain. The genotypes comprised 5 alleles of the argF gene, 9 of rho, 8 of recA, and 10 of the 16S ribosomal DNA. Sequence analysis by determination of homoplasy ratios and split decomposition analysis revealed abundant recombination within N. lactamica.

Solid matrix-antibody-antigen complexes incorporating equine herpesvirus 1 glycoproteins C and D elicit anti-viral immune responses in BALB/c (H-2K(d)) and C3H (H-2K(k)) mice.

Glycoproteins C and D (gC and gD) derived from equine herpesvirus 1 (EHV-1)-infected cells were incorporated into individual solid matrix-antibody-antigen (SMAA) complexes and administered to BALB/c (H-2K(d)) and C3H (H-2K(k)) mice. Antibodies against each of the glycoproteins were produced that neutralised virus infectivity and mediated the lysis of EHV-1-infected target cells in the presence of complement. Immunoglobulin (Ig)G2b was the predominant antibody isotype produced in BALB/c mice against gC, while equal amounts of IgG2a/2b were found in the serum of C3H mice (indicative of a T-helper(1) response). Glycoprotein D immunisation elicited predominantly an IgG1 response in BALB/c mice (indicative of a T-helper(2) response) and an IgG2a/2b response in C3H mice. EHV-1-specific local and systemic T-cell proliferative responses were detected in vitro following administration of SMAA complexes. Suppression of the local T-cell response was seen following virus challenge of mice immunised with SMAA gC. SMAA gD provided some protection against intranasal EHV-1 challenge. These data show that the SMAA system is an effective way of presenting subviral components to the immune system and further emphasises the importance of including glycoprotein D as a component of a subunit EHV-1 vaccine.

Cloning and functional characterization of a 30 kb gene locus required for lipopolysaccharide biosynthesis in Legionella pneumophila.

The spontaneous Legionella pneumophila lipopolysaccharide (LPS) mutant 137, which did not bind the LPS-specific mAb 2625, was complemented with a genomic library from the parental wild-type strain. Transformants were screened for reconstitution of the wild-type LPS phenotype, able to bind mAb 2625. By this strategy, a 32,661 bp region comprising 30 open reading frames (Orfs) was identified. Orfs with significant homologies to genes encoding enzymes required for LPS or capsule biosynthesis of Gram-negative bacteria were located on the gene locus. The mutation of strain 137 could be assigned to a deletion of a cytosine residue in Orf 8. The protein encoded by Orf 8 exhibited homology to bacterial methyl-transferases. The L. pneumophila LPS gene locus included genes with deduced products likely to be involved in LPS core oligosaccharide biosynthesis (rmlA-D, rhamnosyl-transferases, acetyl-transferase) as well as LPS O-chain biosynthesis and translocation (mnaA, neuB, neuA, wecA, wzt, wzm). The neuA (Orf 25) and neuB (Orf 24) gene products were functionally characterized by complementation of the capsule negative E. coli K1 mutants EV5 and EV24, respectively. By introduction of the L. pneumophila neuA gene into E. coli EV5 and the neuB gene into EV24, expression of the K1 polysialic acid capsule could be restored. We, therefore, conclude that the biosynthesis pathway of legionaminic acid, the structural unit of the L. pneumophila Sg1 O-antigen, might be similar to the biosynthesis of sialic acid. Southern blot analysis indicated the entire gene locus to be present in L. pneumophila serogroup (Sg)1 strains, whereas only parts of the DNA stretch hybridized to DNA from Sg2 to Sg14 strains.

Herpesvirus infection accelerates atherosclerosis in the apolipoprotein E-deficient mouse.

BACKGROUND: Human herpesviruses have been implicated but not proven to be involved in the etiology of atherosclerosis. To determine whether there is a causal relationship, the effect of herpesvirus infection on the development of atherosclerosis was assessed in the apolipoprotein E-deficient (apoE-/-) mouse. METHODS AND RESULTS: In the present study, 3- to 4-week-old apoE-/- mice were infected with murine gamma-herpesvirus-68 (MHV-68). Atheroma formation was accelerated over a 24-week period in infected apoE-/- mice compared with control uninfected apoE-/- mice. Acceleration of atherosclerosis was reduced by antiviral drug administration. Histological analysis of the atheromatous plaques showed no difference between lesions of infected and control mice. Viral mRNA was present in the aortas of infected mice before lesion development on day 5 after infection. This suggests that the virus may initiate endothelial injury, which is believed to be an early event in the development of atherosclerosis. Therefore, the virus may play a direct role in atherosclerosis rather than be an "innocent bystander." CONCLUSIONS: These data demonstrate that a gamma-herpesvirus can accelerate atherosclerosis in the apoE-/- mouse. This study provides the first report of a murine model in which to study the causative role of herpesvirus infection in the development of atherosclerosis.

Determination of Zn in high-purity GaAs with neutron activation analysis

Neutron activation analysis was used to analyse Zn concentrations in high-purity GaAs. A combination of chemical separation of the neutron-induced 65Zn from the GaAs-matrix with anion-exchange chromatography and ultra low-level gamma-ray spectrometry in an underground laboratory was applied. Zn concentration ranged from 2.1 to 51 ng g(-1), and detection limits from 0.018 to 0.059 ng g(-1) were obtained.

A broad spectrum PCR method for the detection of polyomaviruses and avoidance of contamination by cloning vectors.

Polyomaviruses induce tumours of different histological types when inoculated into experimental animals, but their aetiological role in the development of malignant tumours in humans remains questionable. We developed a degenerate PCR assay in an attempt to identify additional, presently unknown human polyomavirus types which may be involved in the malignant transformation of human tissues. Degenerate oligonucleotide primers were deduced from four different conserved amino acid motifs in the highly conserved viral capsid protein, VP1. Three different sets of primers were included for the each test. Bladder carcinomas, Hodgkin's lymphomas, meningiomas, Kaposi-tumours and -cell lines were analysed. No polyomavirus DNA sequences could be detected. A comparative analysis led to the recognition of the presence of SV40 DNA sequences in more than 200 vectors available in the EMBL and Genbank Databanks and commonly used in laboratories worldwide. The majority of primers used to detect polyomavirus sequences in human tumours are distributed throughout these regions also present in the vectors. Only a small stretch of 286bp in the overlapping region of the VP1, VP2 and VP3 genes is not present in the vector sequences. We propose to use this region for the design of additional non-contamination primers.

Screening human tumor samples with a broad-spectrum polymerase chain reaction method for the detection of polyomaviruses.

Polyomaviruses induce tumors of different histological types when inoculated into experimental animals. An etiological role for this virus group in the development of malignant tumors in humans remains questionable, despite several reports demonstrating the presence of SV40, JCV, and BKV DNA in human cancers. Only two human polyomavirus types are known to date: JCV, causing progressive multifocal leukoencephalopathy (PML) under severe immunosuppression, and BKV, first isolated from the urine of a renal transplant recipient and associated with hemorrhagic cystitis. We developed a degenerate polymerase chain reaction assay in an attempt to identify additional, presently unknown human polyomavirus types that may be involved in the malignant transformation of human tissues. A large part of the gene coding for the viral capsid protein VP1 is highly conserved in nine polyomavirus types (and their strains) and was therefore selected as most suitable for the primer design. Degenerate oligonucleotide primers were deduced from four different conserved amino acid motifs in this region. Three different sets of primers were included in each test to obtain the highest sensitivity in combination with primers with the lowest degeneracy numbers. The sensitivity obtained ranged from 1 copy/cell for bovine polyomavirus to 100 copies/cell for LPV after ethidium bromide staining and was increased at least 10-fold after hybridization with a radiolabeled probe. A subsequent seminested amplification allowed for the detection of 1 copy/cell for LPV. These degenerate primers were applied to analyze bladder carcinomas, Hodgkin lymphomas, meningiomas, Kaposi tumors, and Kaposi-derived cell lines. No polyomavirus DNA sequences could be detected.

The production of a truncated form of baculovirus expressed EHV-1 glycoprotein C and its role in protection of C3H (H-2Kk) mice against virus challenge.

A truncated form of the equine herpesvirus 1 (EHV-1) glycoprotein C (gC) gene was expressed in baculovirus. The gC signal sequence was substituted with the honeybee melittin signal sequence and the transmembrane region was replaced with a histidine tag. The recombinant virus produced high levels of gC in both the cells and supernatants of infected cells. The protein was present by 24 h and maximal secretion occurred at 96 h post-infection. The recombinant protein was antigenically authentic as shown by its reaction with each of a panel of individual monoclonal antibodies specific for the five distinct antigenic sites on EHV-1 gC. Recombinant gC was purified from the supernatant of infected cells by immuno-affinity chromatography and used to immunize C3H (H-2Kk haplotype) mice. This incurred a gC specific antibody response against both the recombinant protein and EHV-1 gC. 'Pepscan' analysis showed that the gC specific antibodies in serum from these mice reacted with the same epitopes on gC as those recognized by antibodies in convalescent equine sera (i.e. antibodies were specific to antigenic sites one and five). A third previously unrecognized antibody binding site at the carboxyl terminus was also detected (Antibody binding domain I). A T-cell proliferative response against EHV-1 was detected in splenocyte populations taken from vaccinated mice. Further, the recovery of virus from the lungs and turbinates following challenge of mice with EHV-1 was significantly reduced. These findings indicate that baculovirus expressed gC may contribute significantly to a subunit vaccine preparation aimed at protecting horses from EHV-1 infection.