Ecotoxicity of plant extracts and essential oils: A review.

Plant-based products such as essential oils and other extracts have been used for centuries due to their beneficial properties. Currently, their use is widely disseminated through a variety of industries and new applications are continuously emerging. For these reasons, they are produced industrially in large quantities and consequently they have the potential to reach the environment. However, the potential effects that these products have on the ecosystems' health are mostly unknown. In recent years, the scientific community started to focus on the possible toxic effects of essential oils and plant extracts towards non-target organisms. As a result, an increasing body of knowledge has emerged. This review describes the current state of the art on the toxic effects that essential oils and plant extracts have towards organisms from different trophic levels, including producers, primary consumers, and secondary consumers. The majority of the studies (76.5%) focuses on the aquatic environment, particularly in aquatic invertebrates (45.1%) with only 23.5% of the studies focusing on the potential toxicity of plant-derived products on terrestrial ecosystems. While some essential oils and extracts have been described to have no toxic effects to the selected organisms or the toxic effects were only observable at high concentrations, others were reported to be toxic at concentrations below the limit set by international regulations, some of them at very low concentrations. In fact, L(E)C50 values as low as 0.0336 mg.L-1, 0.0005 mg.L-1 and 0.0053 mg.L-1 were described for microalgae, crustaceans and fish, respectively. Generally, essential oils exhibit higher toxicity than extracts. However, when the extracts are obtained from plants that are known to produce toxic metabolites, the extracts can be more toxic than essential oils. Overall, and despite being generally considered "eco-friendly" products and safer than they synthetic counterparts, some essential oils and plant extracts are toxic towards non-target organisms. Given the increasing interest from industry on these plant-based products further research using international standardized protocols is mandatory.

Chemical characterization and bioactive potential of Thymus×citriodorus (Pers.) Schreb. preparations for anti-acne applications: Antimicrobial, anti-biofilm, anti-inflammatory and safety profiles.

ETHNOPHARMACOLOGICAL RELEVANCE: Thymus × citriodorus (Pers.) Schreb. is an interspecific hybrid between Thymus pulegioides and Thymus vulgaris, known for its pharmacological activities as diaphoretic, deodorant, antiseptic and disinfectant, the last mostly related with its antimicrobial activity. The folk use of other extracts, as hydrolates, have also been disseminated, as regulators of oily skin with anti-acne effect. AIM OF THE STUDY: We aimed to evaluate the anti-acne potential of two Thymus x citriodorus (TC) preparations, the essential oil (EO) and the hydrolate, to be used as active ingredients for skin applications. Specifically, we intend to validate their anti-acne potential by describing their activity on acne related bacteria, bacterial virulence, anti-oxidant and anti-inflammatory potential, and biocompatibility on inflammatory cells. Additionally, we aimed to report their ecotoxicity under the Globally Harmonized System of Classification and Labelling of Chemicals (GHS), thus focusing not only on the consumer, but also on environmental safety assessment. MATERIALS AND METHODS: Minimum inhibitory concentration (MIC) against C. acnes, S. aureus and S. epidermidis was evaluated. Minimum lethal concentration (MLC) was also determined. The effect on C. acnes biofilm formation and disruption was evaluated with crystal violet staining. Anti-inflammatory activity was investigated on LPS-stimulated mouse macrophages (RAW 264.7), by studying nitric oxide (NO) production (Griess reagent) and cellular biocompatibility through MTT assay. In-vitro NO and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging potential were also evaluated. The ecotoxicity was evaluated using Daphnia magna acute toxicity assays. RESULTS: EO presented direct antimicrobial activity, with visual MICs ranging from 0.06% for S. epidermidis and C. acnes to 0.125% for S. aureus. MLCs were higher than the obtained MICs. Hydrolate revealed visual MIC only for C. acnes. TC essential oil was effective in preventing biofilm formation and disrupting preformed biofilms even at sub-inhibitory concentrations. Hydrolate showed a more modest anti-biofilm effect. Regarding anti-inflammatory activity, TC hydrolate has a higher cellular biocompatibility. Still, both plant preparations were able to inhibit at least 50% of NO production at non-cytotoxic concentrations. Both EO and hydrolate have poor anti-oxidant activities. Regarding the ecotoxicity, TC essential oil was classified under acute 3 category, while the hydrolate has proved to be nontoxic, in accordance to the GHS. CONCLUSIONS: These results support the anti-acne value of different TC preparations for different applications. TC hydrolate by presenting higher biocompatibility, anti-inflammatory potential and the ability to modulate C. acnes virulence, can be advantageous in a product for everyday application. On the other hand, EO by presenting a marked antimicrobial, anti-biofilm and anti-inflammatory activities, still with some cytotoxicity, may be better suited for application in acute flare-ups, for short treatment periods.

Vascular considerations in the Le Fort I osteotomy: results of analysis of 16 cases / Considerações vasculares na osteotomia Le Fort I: resultados da análise de 16 casos

OBJECTIVE: To review the vascular principles of the Le Fort I osteotomy together with a retrospective analysis of the following factors in 16 cases: ligature of the descending palatine arteries, bone segmentations and the types of surgical movements. RESULTS AND DISCUSSION: Mild complications occurred in two patients who had osteotomies in two places. Both had ligature of the palatine descending arteries and superior repositioning with impaction of the posterior maxilla greater than 4 mm. CONCLUSION: According to the literature and the obtained results, the Le Fort I osteotomywithout segmentation presents as a very safe procedure for the correction of maxillary deformities. The ligature of the descending palatine artery does not seem to directly affect the occurrence of ischemic sequelae, except when associated with segmentations and major surgical movements.

OBJETIVO: Revisar os princípios vasculares da osteotomia Le Fort I, juntamente com uma análise retrospectiva dos seguintes fatores, em 16 casos: ligadura da artéria palatina descendente, segmentação óssea e tipos de movimentos cirúrgicos. RESULTADOS E DISCUSSÃO: Complicações discretas ocorreram em dois pacientes submetidos a osteotomias em dois lugares. Ambos tiveram as artérias palatinas desligadas e reposição superior com impactação da maxila posterior maior do que 4 mm. CONCLUSÃO: De acordo com a literatura e os resultados obtidos, a osteotomia Le Fort I sem segmentação é um procedimento muito seguro para a correção das deformidades maxilares. A ligadura da artéria descendente palatina parece não afetar diretamente a ocorrência de seqüelas isquêmicas, exceto quando associada com segmentação e movimentos maxilares extensos.

Tratamento ortopédico-funcional das fraturas do côndilo mandibular em crianças: relato de casos / Functional orthopedic treatment of mandibular condyle fractures in children: case reports

Este artigo apresenta uma revisäo de literatura sobre métodos de tratamento (cirúrgico ou conservador) de fraturas de côndilo mandibular em crianças e suas conseqüências (anquilose e/ou assimetria), com apresentaçäo de dois casos clínicos tratados conservadoramente com aparelhos ortopédicos funcionais