Preparado cardiopulmonar Heart and lung experimental preservatnio

Trata-se de um método de preservação do conjunto coraçâo-pulmâo isolado em condições fisiológicas. Após abertura do tórax, é instituída a autoperfusâo ex-corpore que se obtém pela canulação do tronco braquicefálico e veia cava superior, conectando-se a um reservatório situado a 1 metro de altura, de tal maneira que, pela contração ventricular esquerda, o sangue é impulsionado ao reservatório, retorna ao coração direito e segue as vias normais, passando pelos pulmões, onde é oxigenado. A seguir, sem qualquer interrupção dos batimentos e da ventilação, o bloco é retirado do tórax e acondicionado no Recipiente para Conservação e Transporte do Conjunto Cardiopulmonar à temperatura normal. Foram empregados 28 cães, com peso entre 18 e 28 kg, tendo sido feito 8 preservações, para se testar o método, e 10 preservações, para transplante cardiopulmonar em 10 cães receptores. Foram monitorizados, continuamente, eletrocardiograma, pressão intraórtica, pressão ventricular esquerda, DP/DT, índice tempo-tensáo e trabalho cardíaco que mostraram valores estáveis e satisfatórios, tanto na fase de preservação, quanto após o transplante. Os gases sangüíneos guardaram relação com as diferentes misturas administradas à ventilação. A análise microscópica de fragmentos do músculo cardíaco e tecido pulmonar retirado ao final dos procedimentos não revelou alterações significativas decorrentes do método.<br>A simple method is presented which proved to be effective for maintaining the heart and lungs viable and functioning in good hemodynamic and metabolic conditions outside of the body, for a period of up to 7 hours. After this, the heart-lung preparation is transplanted to another animal which maintains good parameters also for 3 hours. The hemodynamic, biochemical and histological features of this preparation are presented. In conclusion, preservation of a heart-lung allograft in a dynamic state provides a means to transport donor organs over long distances, and appears to be suitable to serve as a graft for heart or heart-lung transplantation

Circulating copper and zinc levels and risk of hepatobiliary cancers in Europeans.

BACKGROUND: Copper and zinc are essential micronutrients and cofactors of many enzymatic reactions that may be involved in liver-cancer development. We aimed to assess pre-diagnostic circulating levels of copper, zinc and their ratio (Cu/Zn) in relation to hepatocellular carcinoma (HCC), intrahepatic bile duct (IHBD) and gall bladder and biliary tract (GBTC) cancers. METHODS: A nested case-control study was conducted within the European Prospective Investigation into Cancer and Nutrition cohort. Serum zinc and copper levels were measured in baseline blood samples by total reflection X-ray fluorescence in cancer cases (HCC n=106, IHDB n=34, GBTC n=96) and their matched controls (1:1). The Cu/Zn ratio, an indicator of the balance between the micronutrients, was computed. Multivariable adjusted odds ratios and 95% confidence intervals (OR; 95% CI) were used to estimate cancer risk. RESULTS: For HCC, the highest vs lowest tertile showed a strong inverse association for zinc (OR=0.36; 95% CI: 0.13-0.98, Ptrend=0.0123), but no association for copper (OR=1.06; 95% CI: 0.45-2.46, Ptrend=0.8878) in multivariable models. The calculated Cu/Zn ratio showed a positive association for HCC (OR=4.63; 95% CI: 1.41-15.27, Ptrend=0.0135). For IHBC and GBTC, no significant associations were observed. CONCLUSIONS: Zinc may have a role in preventing liver-cancer development, but this finding requires further investigation in other settings