Iberian Margin surface ocean cooling led freshening during Marine Isotope Stage 6 abrupt cooling events.

The high-resolution paleoclimate records on the Iberian Margin provide an excellent archive to study the mechanism of abrupt climate events. Previous studies on the Iberian Margin proposed that the surface cooling reconstructed by the alkenone-unsaturation index coincided with surface water freshening inferred from an elevated percentage of tetra-unsaturated alkenones, C37:4%. However, recent data indicate that marine alkenone producers, coccolithophores, do not produce more C37:4 in culture as salinity decreases. Hence, the causes for high C37:4 are still unclear. Here we provide detailed alkenone measurements to trace the producers of alkenones in combination with foraminiferal Mg/Ca and oxygen isotope ratios to trace salinity variations. The results indicate that all alkenones were produced by coccolithophores and the high C37:4% reflects decrease in SST instead of freshening. Furthermore, during the millennial climate changes, a surface freshening did not always trigger a cooling, but sometimes happened in the middle of multiple-stage cooling events and likely amplified the temperature decrease.

Uso do tamoxifeno no tratamento de quelóides e cicatrizes hipertróficas / Tamoxifen as treatment to keloids and hypertrophic scars

Introdução: Existe pouco entendimento a respeito dos mecanismos que levam à formação dos quelóides e cicatrizes hipertróficas (CHT), assim como não há um tratamento padrão-ouro para essas lesões. Experiências recentes demonstraram que as alterações na formação dessas cicatrizes envolvem concentrações desequilibradas de fatores de crescimento locais, em particular o fator de crescimento transformador (TGF) β1. O tamoxifeno, ao inibir a produção desta citocina, pode ser uma nova opção na conduta terapêutica destas lesões. Método: Dezoito pacientes portadores de quelóides e CHT foram selecionados para a avaliação do uso do citrato de tamoxifeno 0,1% por um período de seis meses. Durante essa evolução, foi realizado registro fotográfico, mensuração e análise histopatológica das lesões e questionários relativos a aspectos da lesão foram aplicados aos pacientes. Resultados: Houve redução significativa da altura(p < 0,0001), da largura (p = 0,009) e do comprimento (p = 0,009) das lesões. Os critérios de textura, altura e prurido foram os que obtiveram as maiores variações entre os períodos pré e pós-tratamento. As alterações histológicas sugerem uma ação de remodelamento do colágeno nessas cicatrizes. Conclusões: O citrato de tamoxifeno apresentou uma resposta favorável na maioria dos critérios analisados, mínimos efeitos colaterais e baixo custo, constituindo uma opção de tratamento segura e cômoda, principalmente nas CHT. São necessários novos estudos com maior amostragem para obtenção de conclusões mais abrangentes.

Background: Keloids and hypertrophic scars (HScs) are poorly understood cicatricial lesions without a gold-standard treatment. Recent experiments demonstrated that cytokines imbalance has an action in scar pathogenesis, mainly due to transforming growth factor (TGF) β1 over expression. Tamoxifen, an antioestrogenic drug, can inhibit TGF-β1 release and consequently fibroblastic proliferation. This indicates a possible role of Tamoxifen as a therapeutic option in keloids and HScs. Method: Eighteen patients were selected for the evaluation of tamoxifen citrate 0.1% for six months. During that evolution, photographic registration, dimensional evaluation and hystopathologic analisis of the lesions were accomplished and questionnaires about aspects of the lesion were applied to patients. Results: There was a significant reduction of the lesion height (p < 0.0001), width (p = 0.009) and length (p = 0.009). Texture criteria, height and itch were the ones that obtained the largest variations among the periods before and after treatment. Histological changes suggested remodelling action of the collagen in those scars. Conclusions: Tamoxifen citrate presented positive results in most of the analyzed criteria, minima side effects and low cost, constituting a safe and comfortable treatment option, mainlyin HScs. There will be necessary more research with larger sampling for greater conclusions.

Lipoabdominoplastia - Técnica Saldanha / Lipoabdominoplasty - Saldanha's

The objective of this paper is to present a new surgical concept for the aesthetic treatment of the abdominal region, combining the principles of liposuction and traditional abdominoplasty, without flap detachment. Following the idea of not carrying out traditional supraumbilical detachment and using superficial liposuction, the authors performed lipoabdominoplasty, thus preserving, abdominal perforans vessels, and reducing vascular damages to the skin of the adominal flap