Association between Vitamin D Receptor Gene Polymorphisms and Periodontal Bacteria: A Clinical Pilot Study.

Background: Periodontitis is an inflammatory disease caused by microorganisms involving the supporting tissues of the teeth. Gene variants may influence both the composition of the biofilm in the oral cavity and the host response. The objective of the study was to investigate the potential correlations between the disease susceptibility, the presence and the quantity of periodontopathogenic oral bacterial composition and the VDR gene polymorphisms. Methods: Fifty (50) unrelated periodontal patients and forty-one (41) healthy controls were selected for genomic DNA extraction. DNA concentration was measured and analyzed. The periodontopathogenic bacterial species were identified and quantified using a Real Time PCR performed with species-specific primers and probes. Results: Genotype distribution showed a different distribution between the groups for BsmI rs1544410 genotypes (p = 0.0001) with a prevalence of the G(b) allele in periodontal patients (p = 0.0003). Statistical significance was also found for VDR TaqI rs731236 (p ≤ 0.00001) with a prevalence of the T(T) allele in periodontal patients (p ≤ 0.00001). The average bacterial copy count for the periodontitis group was significantly higher than that of control group. Dividing patients into two groups based on high or low bacterial load, FokI rs2228570 T allele (f) was statistically more represented in patients with high bacterial load. Conclusions: The findings of the study suggest the involvement of the VDR gene BsmI and TaqI polymorphisms in periodontal disease, while FokI and BsmI may be involved in determining an increased presence of periodontopathogens.

SARS-CoV-2 infection after vaccination in Italian health care workers: a case report.

Following the approval of COVID-19 vaccination program by EMA and national authorities, an immunization campaign started in Italy with BNT162b2mRNA vaccine, initially focused on healthcare workers. The active immunization was monitored by systemic antibody titration and continuous surveillance was guaranteed by antigenic/molecular tests on swabs. Cases of infection have been recently observed in vaccinated healthcare workers. Herein we describe an outbreak of infection occurring in five physicians out of 656 healthcare workers belonging to a private hospital, referring mild symptoms of COVID-19. Healthcare workers underwent complete vaccination and screening for antibody titration. Five out of 656 healthcare workers were tested positive for SARS-CoV-2 in nasopharyngeal swabs and referred mild COVID-19 symptoms. Molecular analyses were carried out to identify possible variants of Spike protein. Their genotyping performed on RNA extracts highlighted the presence of del69/70, N501Y, A570D, and 1841A > G (D614G) sequence variants, all indicative of VOC 202012/01-lineage B.1.1.7, suggesting a common source of infection. These cases might represent a serious emergency because outbreaks can compromise frail patients with important concomitant diseases.

Pharmacogenetic-Based Interactions between Nutraceuticals and Angiogenesis Inhibitors.

Background: Angiogenesis inhibitors (AIs) have become established as an effective cancer treatment. Whereas their interactions with antineoplastic drugs have extensively been investigated, little is known of the effect of their co-administration with nutraceuticals/dietary supplements (N/DSs), which are often self-prescribed. N/DSs comprise a wide range of products such as herbs, nutrients, vitamins, minerals, and probiotics. Assessment of their interactions with cancer drugs, particularly AIs, is hampered by the difficulty of gauging the amount of active substances patients actually take. Moreover, there is no agreement on which approach should be used to determine which N/DSs are most likely to influence AI treatment efficacy. We present a comprehensive review of the metabolic routes of the major AIs and their possible interactions with N/DSs. Methods: The PubMed and Cochrane databases were searched for papers describing the metabolic routes of the main AIs and N/DSs. Results: Data from the 133 studies thus identified were used to compile a diagnostic table reporting known and expected AI-N/DS interactions based on their metabolization pathways. AIs and N/DSs sharing the cytochrome P450 pathway are at risk of negative interactions. Conclusions: Recent advances in pharmacogenetics offer exceptional opportunities to identify prognostic and predictive markers to enhance the efficacy of individualized AI treatments. The table provides a guide to genotyping patients who are due to receive AIs and is a promising tool to prevent occult AI-N/DS interactions in poor metabolizers. N/DS use by cancer patients receiving AIs is a topical problem requiring urgent attention from the scientific community.

Anti-genotoxic ability of α-tocopherol and Anthocyanin to counteract fish DNA damage induced by musk xylene.

Many compounds released into the environment are able to interact with genetic material. The main purpose of genetic toxicology is to investigate the adverse effects of genotoxic molecules such as reduced fitness, changes in gene frequencies and their impact on genetic diversity in populations following genotoxic exposure. However, the ecological effects of many genotoxic compounds remain poorly understood. The aim of this research was to evaluate the genotoxic activity of an artificial musk (musk xylene, MX) and the potential anti-genotoxicity against this chemical compound of two antioxidant substances (α-tocopherol and an anthocyanins enriched extract). The studies were performed both in vivo and in vitro, using the teleost Danio rerio and the DLEC (Dicentrarchus labrax embryonic cells) cell line. We carried out the exposure to these substances at different times. DNA and cell damage and their possible repair were detected by various experimental approaches: DNA strand breaks (Comet Assay), degree of apoptosis (Diffusion Assay) and molecular alterations at the genomic level (RAPD-PCR technique). Data were collected and analyzed for statistical significance using the Student's t test. The results of this study showed that MX exhibited a genotoxic activity even after short exposure times. The anti-genotoxicity experiments evidenced that both α-tocopherol and Anthocyanin were able to contrast the genotoxic effects induced by MX, both in vivo and in vitro.

Genotoxicity assessment of TiO2 nanoparticles in the teleost Danio rerio.

Titanium dioxide nanoparticles (TiO2 NPs), widely used in paints, pharmaceutical preparations and in many consumer products, have been shown to induce cytotoxicity, genotoxicity and carcinogenic responses both in vitro and in vivo. Numerous studies have shown the potential impact of nanoparticles on a series of aquatic organisms and their toxicity has been linked to their dissolution, surface properties and size. In vitro studies have raised concerns about the toxicity of TiO2 NPs, but there are very limited data on ecotoxicity to aquatic life. This in vivo study aimed to describe the genotoxicity of TiO2 NPs in the zebrafish Danio rerio. After 2 weeks of adaptation, groups of zebrafish were exposed to TiO2 NPs (1 and 10µg/L) for 5, 7, 14, 21 and 28 days. The genotoxic potential of TiO2 NPs was assessed by the Comet assay, the Diffusion assay and RAPD-PCR technique. The use of multi-biomarkers has become an important aspect of ecotoxicology to evaluate environmental quality through a wide panel of biological responses triggered by contaminants. The highest genotoxic effect was observed at the maximum concentrations of nanoparticles (10µg/L) with all three tests at 14 and 21 days of exposure. The results suggests the presence of mechanisms that can reduce the n-TiO2 genotoxicity. Future studies are necessary to analyze the DNA repairing capacity in zebrafish cells and so verify the role of the antioxidant defence system in modulating the response to exposure to n-TiO2 in fish.

Environmental genomics: a tale of two fishes.

The influence of the environment on two congeneric fishes, Gillichthys mirabilis and Gillichthys seta, that live in the Gulf of California at temperatures of 10-25 degrees C, and up to 42-44 degrees C, respectively, was addressed by analyzing their genomes. Compared with G. mirabilis, G. seta showed some striking features. Substitution rates in the mitochondrial genes were found to be extremely fast, in fact faster than in noncoding control regions (D-loops), from which a divergence time of less than 0.66-0.75 Mya could be estimated. In the nuclear genome, 1) both AT --> GC/GC --> AT and transversion: transition ratios in coding sequences (CDSs) were relatively high; moreover, the ratios of nonsynonymous/synonymous changes (Ka/Ks) suggested that some genes were under positive selection; 2) DNA methylation showed a very significant decrease; and 3) a GC-rich minisatellite underwent a 4-fold amplification in the gene-rich regions. All these observations clearly indicate that the environment (temperature and the accompanying hypoxia) can rapidly mold the nuclear as well as the mitochondrial genome. The stabilization of gene-rich regions by the amplification of the GC-rich minisatellite and by the GC increase in nuclear CDSs is of special interest because it provides a model for the formation of the GC-rich and gene-rich isochores of the genomes of mammals and birds.

Molecular and karyological aspects of Batoidea (Chondrichthyes, Elasmobranchi) phylogeny.

Although considerable progress has been made in elucidating the relationships within the Chondrichthyes, there is no agreement as it concerns the systematics of Batoidea, the most derived superorder among cartilaginous fishes, and many different interpretations exist. Our investigation provides the first assessment of relationships among the described batoid species using sequences from both mtDNA and nuclear genes as well as karyological morphology. Our work consists primarily in reconstructing the phylogenetic relationships of Batoidea by examining the mtDNA (16S) and nuclear gene (18S) sequences from 11 batoid species. The three analytical methods (NJ, MP and Bayesian analysis) grouped Rajiformes, Myliobatiformes and Rhinobatiformes. In these trees the two torpedoes diverge from the other batoid fishes. We also compare the molecular data with the available karyological evidence, which consist of the diploid number and the karyotype morphology of eight species belonging to the four orders examined. The results show that the karyological structure in the different species is generally consistent with the various phylogenetical trees, and that Torpediniformes confirm their unique genome organization.

Molecular organization of 5S rDNAs in Rajidae (Chondrichthyes): Structural features and evolution of piscine 5S rRNA genes and nontranscribed intergenic spacers.

The genomic and gene organisation of 5S rDNA clusters have been extensively characterized in bony fish and eukaryotes, providing general issues for understanding the molecular evolution of this multigene DNA family. By contrast, the 5S rDNA features have been rarely investigated in cartilaginous fish (only three species). Here, we provide evidence for a dual 5S rDNA gene system in the Rajidae by sequence analysis of the coding region (5S) and adjacent nontranscribed spacer (NTS) in five Mediterranean species of rays (Rajidae), and in a large number of piscine taxa including lampreys and bony fish. As documented in several bony fish, two functional 5S rDNA types were found here also in the rajid genome: a short one (I) and a long one (II), distinguished by distinct 5S and NTS sequences. That the ancestral piscine genome had these two 5S rDNA loci might be argued from the occurrence of homologous dual gene systems that exist in several fish taxa and from 5S phylogenetic relationships. An extensive analysis of NTS-II sequences of Rajidae and Dasyatidae revealed the occurrence of large simple sequence repeat (SSR) regions that are formed by microsatellite arrays. The localization and organization of SSR within the NTS-II are conserved in Rajiformes since the Upper Cretaceous. The direct correlation between the SSRs extension and the NTS length indicated that they might play a role in the maintenance of the larger 5S rDNA clusters in rays. The phylogenetic analysis indicated that NTS-II is a valuable systematic tool limited to distantly related taxa of Rajiformes.

Karyotype and genome characterization in four cartilaginous fishes.

Different approaches can be used to elucidate the unsolved questions concerning taxonomic evolution in cartilaginous fish. The study of the karyological characteristics of these vertebrates by combining molecular and traditional techniques of chromosome preparation and banding has been demonstrated to be a very effective method. In this paper we studied the localization and the composition of the constitutive heterochromatin by using C- and restriction endonuclease-banding in four selachian species, belonging to two of the four superorders. We also characterized two different types of repetitive genomic sequences in these species: satellite DNA and (TTAGGG)(n) telomeric sequences. Finally, we analysed the nuclear ribosomal gene to determine the number of the nucleolar organizers and their position on chromosomes by using silver staining, chromomycin A(3), and FISH (fluorescent in situ hybridization). The results showed a prevailingly telomeric localization of constitutive heterochromatin in the Galeomorphii, the presence of additional nucleolar organizer sites in Raja asterias, an exclusively telomeric localization of the (TTAGGG)(n) sequences in Scyliorhinus stellaris and both telomeric and interstitial in Taeniura lymma. These data, together with those concerning the conservation of the satellite DNA, seem to support the hypothesis that Chondrichthyes have an evolutionary history leading them to the acquisition of large genomes rich in highly repeated sequences and subjected to some selective pressures favoring the conservation of this DNA fraction.