Impact of gingivitis on oral health-related quality of life in 12-year-old schoolchildren of Quito, Ecuador.

PURPOSE: Evaluate the impact of gingivitis on oral health-related quality of life (OHRQoL) amongst 12-year-old schoolchildren from Quito, Ecuador. METHODS: We evaluated 998 school children using the Community Periodontal Index for gingival bleeding and calculus. OHRQoL was assessed with the Child Perceptions Questionnaire 11-14 (CPQ11-14) questionnaire. RESULTS: Of the 998 schoolchildren, 93% had gingival bleeding and 73% had dental calculus. Schoolchildren with more than one sextant with gingival bleeding had 1.18 times higher mean CPQ11-14 (RR 1.18, 95% CI 1.11-1.27) than those with none or just one affected sextant. Male schoolchildren presented a 15% lower mean Child Perceptions Questionnaire (CPQ) (RT 0.85; 95% CI 0.76-0.96). Children whose parents had incomplete secondary education had a 15% lower mean CPQ (RT 0.85; 95% CI 0.77-0.94). Bleeding in more than one sextant was significantly associated with worse quality of life in the emotional well-being (RT 1.40, 95% CI 1.03-1.90) and social well-being domains (RT 1.76, 95% CI 1.32-2.34). CONCLUSION: Gingival bleeding negatively impacted the OHRQoL of 12-year-old Ecuadorian schoolchildren living in Quito.

Efficacy of local phytotherapy in the nonsurgical treatment of periodontal disease: A systematic review.

Herbal drugs are commonly used in the treatment of several diseases, including periodontitis. So far, no systematic review had evaluated the evidence regarding the efficacy of these agents in the treatment of periodontal disease. Therefore, the purpose of this review was to evaluate the effect of local application of phytotherapic agents as adjuncts to scaling and root planing (SRP), compared to SRP alone, on clinical parameters of chronic periodontal patients. Only randomized controlled trials of at least 3 months follow-up, of SRP alone in association with local phytotherapic agents were included. MEDLINE (PubMed), Google Scholar and LILACS databases were searched for articles published up to October 2016. Random-effects meta-analyses were conducted for clinical attachment level and probing pocket depth (PPD) change after treatment. Of 1861 papers potentially relevant, 7 were included. All studies showed that periodontal treatment in association with local phytotherapic delivery promotes a significant PPD reduction and the majority of them showed clinical attachment level gain. The local use of phytotherapy as an adjunct to SRP may promote additional benefits in PPD reduction and clinical attachment level gain. However, these results must be interpreted with caution due to the small sample size, high risk of bias and heterogeneity of the studies.

Detection of a chemical cue from the host seaweed Laurencia dendroidea by the associated mollusc Aplysia brasiliana.

Chemical cues from sessile hosts can attract mobile and associated organisms and they are also impotant to maintain associations and overall biodiversity, but the identity and molecular structures of these chemicals have been little explored in the marine environment. Secondary metabolites are recognized as possible chemical mediators in the association between species of Laurencia and Aplysia, but the identity of the compounds has not been established. Here, for the first time, we experimentally verify that the sesquiterpene (+)-elatol, a compound produced by the red seaweed Laurencia dendroidea, is a chemical cue attracting the associated sea hare Aplysia brasiliana. In addition to revealing the nature of the chemical mediation between these two species, we provide evidence of a chemical cue that allows young individuals of A. brasiliana to live in association with L. dendroidea. This study highlights the importance of chemical cues in Laurencia-Aplysia association.

Okadaic acid, useful tool for studying cellular processes.

One of the most interesting groups of substances of marine origin, from structural and pharmacological points of view are polyether toxins, which generally present a great diversity in size and potent biological activities. The subject of this review is limited to okadaic acid (OA). It was the first example of a group of polyether toxins produced by marine microalgae, which is responsible for the natural phenomena known as Diarrhetic Shellfish Poisoning, DSP red tides. These toxins are accumulated in the digestive glands of the shellfish with a disastrous effect upon the shellfish industry in many parts of the world. Thus, it has been demonstrated that OA is a highly selective inhibitor of protein phosphatases type 1 (PP1) and 2A (PP2A), subsequently that it causes dramatic increases in phosphorylation of numerous proteins as well as being a potent tumour promoter. For that reason, OA is an extremely useful tool for studying the cellular processes that are regulated by reversible phosphorylation of proteins as signal transduction, cell division and memory.

Isolation and structural determination of DTX-6, a new okadaic acid derivative.

Diarrhetic shellfish poisoning is an illness caused by toxins accumulated in shellfish and produced by dinoflagellates, mainly of the Dinophysis and Prorocentrum genera. This paper reports the isolation and spectroscopic structural elucidation of a new compound, DTX-6 (2), an ester derivative of okadaic acid (OA) (1), isolated from an artificial culture of strain PLV2 of Prorocentrum lima.

Influence of amino acids on okadaic acid production.

Okadaic acid (OA) (1)) was the first example of a group of polyether toxins known to be produced by marine microalgae, which are responsible for the natural phenomena known as Diarrhetic Shellfish Poisoning (DSP) red tides. It is also a highly selective inhibitor of protein phosphatases type 1 (PP1) and 2A (PP2A), as well as being a potent tumour promoter. For these reasons, OA is an extremely useful tool for studying cellular processes and an important standard for polluted shellfish control. In this paper, we report on a double objective: to improve the production of toxins and verify the apparent participation of amino acids in the formation of these polyethers by monitoring their influence on the promotion of growth, total cell yield and increased in toxicity in Prorocentrum lima of the PL2V strain in batch cultures, in a modified K medium.

Movement of retinal along the visual transduction path.

Movement of the ligand/receptor complex in rhodopsin (Rh) has been traced. Bleaching of diazoketo rhodopsin (DK-Rh) containing 11-cis-3-diazo-4-oxo-retinal yields batho-, lumi-, meta-I-, and meta-II-Rh intermediates corresponding to those of native Rh but at lower temperatures. Photoaffinity labeling of DK-Rh and these bleaching intermediates shows that the ionone ring cross-links to tryptophan-265 on helix F in DK-Rh and batho-Rh, and to alanine-169 on helix D in lumi-, meta-I-, and meta-II-Rh intermediates. It is likely that these movements involving a flip-over of the chromophoric ring trigger changes in cytoplasmic membrane loops resulting in heterotrimeric guanine nucleotide-binding protein (G protein) activation.

Growth inhibition by dehydrothyrsiferol - a non-Pgp modulator, derived from a marine red alga - in human breast cancer cell lines.

The novel marine terpenoid dehydrothyrsiferol (DHT) has been isolated from a Canarian red alga Laurencia viridis sp. nov (Ceramiales, Rhodomelaceae) (1). Its cytotoxicity against three human breast cancer cell lines, namely T47D, ZR-75-1, and Hs578T was examined and compared with the chemotherapeutic compound doxorubicin and the mitosis-inhibitor colchicine. Primary breast carcinomas exhibit MDR1 gene expression (3). As the investigated mammary cell lines did not exhibit rhodamine 123 efflux we proved in a P-glycoprotein (Pgp) overexpressing human epidermoid cancer cell line that the marine metabolite does not modulate Pgp mediated drug transport. Therefore, it could be used in Pgp expressing cancer cells without interference.

Inhibitory effects of a novel marine terpenoid on sensitive and multidrug resistant KB cell lines.

Mechanisms of growth inhibition by the novel marine compound dehydrothyrsiferol (DHT) were investigated in a sensitive and an MDR+ human epidermoid cancer cell line. DHT was found to circumvent multidrug resistance mediated by P-glycoprotein. Cell cycle analysis revealed an accumulation in S-phase. The anchorage independent clonogenic growth in soft agar was not significantly reduced at IC50 concentrations. Reduced cell growth caused by induction of apoptotic or necrotic cell death could not be verified. Therefore, cell proliferation during an incubation period of five days was measured and found to be significantly reduced. We conclude that growth inhibition by dehydrothyrsiferol in KB cancer cells is not mediated by apoptosis but by growth retardation; the reasons for this are worth being investigated in detail.

Evaluation of the cytotoxic activity of polyethers isolated from Laurencia.

In this paper, we report on the conformational analysis of several polyether triterpenes with a squalene carbon skeleton which exhibited significant cytotoxic activity using a Monte Carlo conformational search and spectroscopical data. These studies indicate that the conformation of the side chain C-14/C-19 and the arrangement and direction of this chain may be among the fundamental factors related to the activity of this type of metabolites.

Complexation of okadaic acid: a preliminary study.

A complexation study was carried out with okadaic acid (OA) and the univalent metal ions Li+, Na+ and K+, and the divalent metal ions Ca2+ and Mg2+. K+ binding was observed identical with a complex obtained from the natural source (OAC). The pharmacological trials demonstrated that this cation has a very important influence on the pharmacological activity of okadaic acid.