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1.  Microsatellite markers for studies with the carnivorous plant Philcoxia minensis (Plantaginaceae)1 
Applications in Plant Sciences  2015;3(8):apps.1500035.
Premise of the study:
Microsatellite markers were developed for the critically endangered carnivorous species Philcoxia minensis (Plantaginaceae) for further population genetic studies aiming at its conservation.
Methods and Results:
We identified 29 clones containing 40 microsatellites from a genomic enriched library. A total of 27 primer pairs were developed and evaluated in 30 individuals of a natural P. minensis population. Seventeen markers successfully presented amplification products within the expected size range, of which 12 were polymorphic. The expected and observed heterozygosities ranged from 0.03 to 0.65 and from 0.00 to 0.77, respectively. Positive transferability with the related species P. bahiensis was observed for the same 17 markers.
The 12 polymorphic microsatellite markers are suitable for studies in genetic diversity and structure, mating system, and gene flow in P. minensis and also may be useful for similar issues regarding the related species P. bahiensis.
PMCID: PMC4542941  PMID: 26312194
conservation genetics; Espinhaço Range; Gratioleae; Philcoxia minensis; Plantaginaceae; simple sequence repeat (SSR)
2.  Metacommunity and phylogenetic structure determine wildlife and zoonotic infectious disease patterns in time and space 
Ecology and Evolution  2015;5(4):865-873.
The potential for disease transmission at the interface of wildlife, domestic animals and humans has become a major concern for public health and conservation biology. Research in this subject is commonly conducted at local scales while the regional context is neglected. We argue that prevalence of infection at local and regional levels is influenced by three mechanisms occurring at the landscape level in a metacommunity context. First, (1) dispersal, colonization, and extinction of pathogens, reservoir or vector hosts, and nonreservoir hosts, may be due to stochastic and niche-based processes, thus determining distribution of all species, and then their potential interactions, across local communities (metacommunity structure). Second, (2) anthropogenic processes may drive environmental filtering of hosts, nonhosts, and pathogens. Finally, (3) phylogenetic diversity relative to reservoir or vector host(s), within and between local communities may facilitate pathogen persistence and circulation. Using a metacommunity approach, public heath scientists may better evaluate the factors that predispose certain times and places for the origin and emergence of infectious diseases. The multidisciplinary approach we describe fits within a comprehensive One Health and Ecohealth framework addressing zoonotic infectious disease outbreaks and their relationship to their hosts, other animals, humans, and the environment.
PMCID: PMC4338969  PMID: 25750713
Disease ecology; dispersal; evolution; metacommunity; One Health; phylogenetic structure; stochastic event
3.  Characterization of Genipin-Modified Dentin Collagen 
BioMed Research International  2014;2014:702821.
Application of biomodification techniques to dentin can improve its biochemical and biomechanical properties. Several collagen cross-linking agents have been reported to strengthen the mechanical properties of dentin. However, the characteristics of collagen that has undergone agent-induced biomodification are not well understood. The objective of this study was to analyze the effects of a natural cross-linking agent, genipin (GE), on dentin discoloration, collagen stability, and changes in amino acid composition and lysyl oxidase mediated natural collagen cross-links. Dentin collagen obtained from extracted bovine teeth was treated with three different concentrations of GE (0.01%, 0.1%, and 0.5%) for several treatment times (0–24 h). Changes in biochemical properties of NaB3H4-reduced collagen were characterized by amino acid and cross-link analyses. The treatment of dentin collagen with GE resulted in a concentration- and time-dependent pigmentation and stability against bacterial collagenase. The lysyl oxidase-mediated trivalent mature cross-link, pyridinoline, showed no difference among all groups while the major divalent immature cross-link, dehydro-dihydroxylysinonorleucine/its ketoamine in collagen treated with 0.5% GE for 24 h, significantly decreased compared to control (P < 0.05). The newly formed GE-induced cross-links most likely involve lysine and hydroxylysine residues of collagen in a concentration-dependent manner. Some of these cross-links appear to be reducible and stabilized with NaB3H4.
PMCID: PMC3984863  PMID: 24795891
4.  Results from the Xylitol for Adult Caries Trial (X-ACT) 
Although caries is prevalent in adults, few preventive therapies have been tested in adult populations. This randomized clinical trial evaluated the effectiveness of xylitol lozenges in preventing caries in elevated caries-risk adults.
X-ACT was a three-site placebo-controlled randomized trial. Participants (n=691) ages 21–80 consumed five 1.0 g xylitol or placebo lozenges daily for 33 months. Clinical examinations occurred at baseline, 12, 24 and 33 months.
Xylitol lozenges reduced the caries increment 11%. This reduction, which represented less than one-third of a surface per year, was not statistically significant. There was no indication of a dose-response effect.
Daily use of xylitol lozenges did not result in a statistically or clinically significant reduction in 33-month caries increment among elevated caries-risk adults.
Clinical Implications
These results suggest that xylitol used as a supplement in adults does not significantly reduce their caries experience.
PMCID: PMC3926805  PMID: 23283923
Xylitol; Dental Caries Prevention; Randomized Controlled Trial; Adults
5.  Examiner Training and Reliability in Two Randomized Clinical Trials of Adult Dental Caries 
This report describes the training of dental examiners participating in two dental caries clinical trials and reports the inter- and intra- examiner reliability scores from the initial standardization sessions.
Study examiners were trained to use a modified ICDAS-II system to detect the visual signs of non-cavitated and cavitated dental caries in adult subjects. Dental caries was classified as no caries (S), non-cavitated caries (D1), enamel caries (D2) and dentine caries (D3). Three standardization sessions involving 60 subjects and 3604 tooth surface calls were used to calculate several measures of examiner reliability.
The prevalence of dental caries observed in the standardization sessions ranged from 1.4% to 13.5% of the coronal tooth surfaces examined. Overall agreement between pairs of examiners ranged from 0.88 to 0.99. An intra-class coefficient threshold of 0.60 was surpassed for all but one examiner. Inter-examiner unweighted kappa values were low (0.23– 0.35) but weighted kappas and the ratio of observed to maximum kappas were more encouraging (0.42– 0.83). The highest kappa values occurred for the S/D1 vs. D2/D3 two-level classification of dental caries, for which seven of the eight examiners achieved observed to maximum kappa values over 0.90.Intra-examiner reliability was notably higher than inter-examiner reliability for all measures and dental caries classification systems employed.
The methods and results for the initial examiner training and standardization sessions for two large clinical trials are reported. Recommendations for others planning examiner training and standardization sessions are offered.
PMCID: PMC3683245  PMID: 22320292
dental caries; early diagnosis; reproducibility of results; ICDAS-II; clinical trial; examiner training; examiner standardization
6.  Mesenchymal stem cells from Shwachman–Diamond syndrome patients display normal functions and do not contribute to hematological defects 
Blood Cancer Journal  2012;2(10):e94-.
Shwachman–Diamond syndrome (SDS) is a rare inherited disorder characterized by bone marrow (BM) dysfunction and exocrine pancreatic insufficiency. SDS patients have an increased risk for myelodisplastic syndrome and acute myeloid leukemia. Mesenchymal stem cells (MSCs) are the key component of the hematopoietic microenvironment and are relevant in inducing genetic mutations leading to leukemia. However, their role in SDS is still unexplored. We demonstrated that morphology, growth kinetics and expression of surface markers of MSCs from SDS patients (SDS-MSCs) were similar to normal MSCs. Moreover, SDS-MSCs were able to differentiate into mesengenic lineages and to inhibit the proliferation of mitogen-activated lymphocytes. We demonstrated in an in vitro coculture system that SDS-MSCs, significantly inhibited neutrophil apoptosis probably through interleukin-6 production. In a long-term coculture with CD34+-sorted cells, SDS-MSCs were able to sustain CD34+ cells survival and to preserve their stemness. Finally, SDS-MSCs had normal karyotype and did not show any chromosomal abnormality observed in the hematological components of the BM of SDS patients. Despite their pivotal role in the hematopoietic stem cell niche, our data suggest that MSC themselves do not seem to be responsible for the hematological defects typical of SDS patients.
PMCID: PMC3483621  PMID: 23064742
Shwachman–Diamond syndrome; mesenchymal stem cells; bone marrow failure; SBDS
7.  Morphology and Behavior of the Early Stages of the Skipper, Urbanus esmeraldus, on Urera baccifera, an Ant—Visited Host Plant 
The Neotropical genus Urbanus (Hübner) (Lepidoptera: Hesperiidae) contains around 34 described species, and is widely distributed from the extreme southern United States to Argentina. Here, we describe the larval morphology and behavior of Urbanus esmeraldus (Hübner)(Hesperiidae) in Urera baccifera (Urticaceae), a plant producing food rewards and fleshy fruits that attract ants (including predacious species) in a Brazilian forest. Larvae pass through five instars and construct two kinds of leaf shelters. Experiments with ejected fecal pellets showed that these can serve as cues to ground—dwelling ants that climb onto host plants and potentially attack the larvae. Manipulation with pellets placed at different distances suggests that ejection behavior decreases larval vulnerability to ant predation. Larval preference for mature leaves may be related with increased predation risk at ant—visited young leaves. The study shows that a combination of natural history and experimental data can help understand the life history of a butterfly using a plant with high predation risk.
PMCID: PMC3499095  PMID: 22953699
ant predation; Atlantic forest; butterfly; ejection behavior; fecal pellets; Hesperiidae; immature stages; leaf shelter; Urticaceae
8.  Root Caries Risk Indicators: A Systematic Review of Risk Models 
To identify risk indicators that are associated with root caries incidence in published predictive risk models.
Abstracts (n=472) identified from a MEDLINE, EMBASE, and Cochrane registry search were screened independently by two investigators to exclude articles not in English (n=39), published prior to 1970 (none), or containing no information on either root caries incidence, risk indicators, or risk models (n=209). A full-article duplicate review of the remaining articles (n=224) selected those reporting predictive risk models based on original/primary longitudinal root caries incidence studies. The quality of the included articles was assessed based both on selected criteria of methodological standards for observational studies and on the statistical quality of the modeling strategy. Data from these included studies were extracted and compiled into evidence tables, which included information about the cohort location, incidence period, sample size, age of the study participants, risk indicators included in the model, root caries incidence, modeling strategy, significant risk indicators/predictors, and parameter estimates and statistical findings.
Thirteen articles were selected for data extraction. The overall quality of the included articles was poor to moderate. Root caries incidence ranged fro m 12%–77% (mean±SD=45%±17%); follow-up time of the published studies was ≤10 years (range=9; median=3); sample size ranged from 23–723 (mean±SD=264±203; median=261); person-years ranged from 23–1540 (mean±SD=760±556; median=746). Variables most frequently tested and significantly associated with root caries incidence were (times tested; % significant; directionality): baseline root caries (12; 58%; positive); number of teeth (7; 71%; 3 times positive, twice negative), and plaque index (4; 100%; positive). Ninety-two other clinical and non-clinical variables were tested: 27 were tested 3 times or more and were significant between 9% and 100% of the times tested; and 65 were tested but never significant.
The root caries incidence indicators/predictors most frequently reported were root caries prevalence at baseline, number of teeth, and plaque index. This finding can guide targeted root caries prevention. There was substantial variation among published models of root caries risk in terms of variable selection, sample size, cohort location, assessment methods, incidence periods, association directionality, and analytical techniques. Future studies should emphasize variables frequently tested and often significant, and validate existing models in independent databases.
PMCID: PMC2962697  PMID: 20545716
9.  Nymphalid butterflies diversify following near demise at the Cretaceous/Tertiary boundary 
The butterfly family Nymphalidae contains some of the most important non-drosophilid insect model systems for evolutionary and ecological studies, yet the evolutionary history of the group has remained shrouded in mystery. We have inferred a robust phylogenetic hypothesis based on sequences of 10 genes and 235 morphological characters for exemplars of 400 of the 540 valid nymphalid genera representing all major lineages of the family. By dating the branching events, we infer that Nymphalidae originated in the Cretaceous at 90 Ma, but that the ancestors of 10–12 lineages survived the end-Cretaceous catastrophe in the Neotropical and Oriental regions. Patterns of diversification suggest extinction of lineages at the Cretaceous/Tertiary boundary (65 Ma) and subsequent elevated speciation rates in the Tertiary.
PMCID: PMC2817107  PMID: 19793750
Lepidoptera; Nymphalidae; mass extinction; times of divergence; diversification

Results 1-9 (9)