Concentration in saliva and antibacterial effect of xylitol chewing gum : in vivo and In vitro study

Purpose. The saliva concentration of xylitol released from two chewing gums was recorded, the first containing xylitol as the only sweetener (100% xylitol) and the second containing only 22% of the polyol. In addition, the in vitro antibacterial effect of the two chewing gums was evaluated. Materials and Methods. The salivary concentration of Xylitol in 32 subjects was determined before and at 0.30, 1.00, 2.00, 5.00, and 10.00 min while using the chewing gums, and at 15.00, 20.00, and 25.00 min after the gums were discarded. In vitro antibacterial activity was determined on a pooled subgingival plaque sample obtained from four patients with periodontal disease. Cariogenic and periodontal bacteria were evaluated before and 15 min, 60 min, and 24 h after gum contact. Results. Using the 100% xylitol chewing gum, saliva levels increased bimodally, one peak after 30 s (1.49 \ub1 1.41 log\u3bcg/L) and a second one at a 10-min evaluation (1.41 \ub1 1.11 log\u3bcg/L); the 22% chewing gum peaked only two minute after contact (1.21 \ub1 1.24 log\u3bcg/L). Overall, a statistically significantly higher salivary concentration of xylitol was detected using the 100% xylitol gum. All bacteria decreased after the addition of the two chewing gums; the 100% gum achieved a greater decrease than the 22% gum. Conclusion. The use of both chewing gums increased the concentrations of xylitol in saliva, with a statistically significantly higher concentration using the 100% xylitol gum. Cariogenic and periodontal bacteria were reduced by both chewing gums; 100% xylitol gum produced the highest and longest lasting effect. This study opens up to the use of xylitol against periodontal disease

Comparison of ICDAS, CAST, Nyvad’s Criteria, and WHO-DMFT for Caries Detection in a Sample of Italian Schoolchildren

Caries measurement methods vary considerably in terms of the stages of lesion considered making the comparison problematic among different surveys. In this cross-sectional study, four caries measurement methods, the WHO-DMFT, the International Caries Detection and Assessment System (ICDAS), the Caries Assessment Spectrum and Treatment (CAST), and the Nyvad Criteria were tested in a sample of children. Five-hundred 12-year old children (236 males and 264 females) were examined four times by four calibrated examiners. The calibration process showed that Cohen\u2019s Kappa exceeded the criterion of K = 0.75 and K = 0.80 for inter/intra-examiner agreement, respectively. In the survey, the total number of misclassification errors for the four methods amounted to 312 observations (67.94% regarding enamel lesions). The greatest difference among methods was shown by number of sound teeth (p < 0.01): WHO-DMFT n = 9505, 74.14%; ICDAS n = 2628, 20.49%; CAST n = 5053, 39.41%; and Nyvad Criteria n = 4117, 32.11%. At the level of dentinal Distinct/Active Cavity lesions, no statistically significant difference was observed (p = 0.40) between ICDAS (n = 1373, 10.71%), CAST (n = 1371, 0.69%), and Nyvad Criteria (n = 1720, 13.41%). In the severe caries levels, all methods were partially in agreement, while no accordance was found for the initial (enamel) lesions. A common language in caries detection is critical when different studies are compared

Global radiant flux from active volcanoes: the 2000–2019 MIROVA database

Since 2000, the Moderate Resolution Imaging Spectroradiometer (MODIS) has acquired infrared images of the Earth’s surface daily. These data have made it possible to measure the thermal energy radiated by the world’s most famous volcanoes and also to discover and track eruptions in remote and poorly monitored regions. In this work, we present the database of Volcanic Radiative Power (VRP, in W) time series, recorded by the MIROVA (Middle Infrared Observation of Volcanic Activity) system over 2 decades of MODIS observations (2000–2019) at 111 active volcanoes. The database reveals that globally, the number of thermally active volcanoes each year varies between 60 and 80, almost equally partitioned between volcanoes with a basic (50%) and intermediate (45%) composition, while only 5% is represented by volcanoes erupting acidic lavas. Within the investigated period, the global-scale heat flux was almost stationary, and occasionally punctuated by peaks associated with the largest effusive eruptions (e.g., Bardarbunga and Kilauea). The Volcanic Radiative Energy (VRE, in J) emitted by basic volcanoes (~1.8 × 1018 J) in 20 years constitutes 91% of the total, while intermediates and acids contribute only 8% (~1.8 × 1017 J) and 1% (~1.7 × 1016 J), respectively. A comparison with the volume of lava erupted effusively by the same volcanoes reveals that this difference is attributed to the lower efficiency in radiating thermal energy of increasingly acidic (viscous) lava bodies. Each compositional group is associated with a specific relationship between VRE and erupted volume which characterises most of the effusive volcanoes. On the other hand, some open-vent volcanoes reveal that much more heat is released than that theoretically radiated by the erupted lava. This imbalance (hereby called excess radiation) is attributed to an additional heat source, likely associated with an underlying convective magma column and/or to outgassing through a permeable conduit. We are convinced that the database presented in this work will be useful to support new emerging studies on globalscale volcanism and will contribute to a better understanding of each volcanic system

Multiproxy archaeological investigation and Garden Archaeology in the Charterhouse of Calci (Tuscany, central Italy) and its territory: results and research data

A wide-ranging archaeological research programme at the Charterhouse and in the broader area of the Municipality of Calci has been performed since 2018. The archaeological research included the collection of legacy and aerial archaeology data, invasive and non-invasive investigations, as well as natural scientific analysis in the monastic complex. Special attention was paid to the archaeological investigations of three different monks’ cells gardens (the Prior’s, the Apothecary’s, and the Master’s), and stratigraphic excavations were combined with archeozoological and archaeobotanical analyses to define the horticultural practices implemented over the centuries of occupation of the Charterhouse. Among the three case studies, the most representative is the Prior’s meditation garden, where the excavation explored the phases prior to the construction of the building (14th century), the 18th-century renovation in the current form, and its abandonment at the end of the 20th century. Pollen analysis has allowed to reconstruct the richness of herbal species characterising an ever-blooming garden, with flowers and ornamental plants, such as roses, lilac, and water lilies, and also vegetables. According to charcoal and fruit-remain analyses, the Charterhouse exploited local hilly woods, satisfying the requirements of fuel by maquis and thermophilous deciduous forest. The agricultural practices included the cultivation of fruit trees, such as chestnut, olive, almond, and vine. Finally, archaeozoological analysis attests the domestic cat as the most frequent taxon in all contexts, probably common in the monastery as a pet and cell companion. This paper presents an overview and a discussion of the results of the investigations conducted and the complete archaeological dataset

Unbalanced 1q Whole-Arm Translocation Resulting in der(14)t(1;14)(q11–12;p11) in Myelodysplastic Syndrome

Unbalanced whole-arm translocations (WATs) of the long arm of chromosome 1, resulting in complete trisomy 1q, are chromosomal abnormalities detectable in both solid tumors and hematologic neoplasms. Among the WATs of 1q to acrocentric chromosomes, a few patients with der(1;15) described as a dicentric chromosome have been reported so far, whereas cases of der(1;14) are much rarer. We report on a case of der(1;14) detected as single anomaly in a patient with myelodysplastic syndrome. The aim of our work was to investigate the breakpoints of the (1;14) translocation leading to the der(1;14). Fluorescence in situ hybridization (FISH) experiments have been performed on chromosome preparations from bone marrow aspirate, using specific centromeric probes of both chromosomes, as well as a probe mapping to 1q11 band. FISH results showed that in our patient the derivative chromosome was monocentric with a unique centromere derived from chromosome 14. The breakpoints of the translocation were located in the short arm of chromosome 14 and in the long arm of chromosome 1, between the alphoid D1Z5 and the satellite II domains. The 1q breakpoint was within the pericentromeric region of chromosome 1, which is notoriously an unstable chromosomal region, involved in different chromosomal rearrangements