Active spleno-femoral shunt avoids splanchnic congestion during portal triad occlusion: An experimental study

Portal triad occlusion (PTO) is often performed during hepatic resections for trauma or malignancies to minimize intraoperative blood loss. the pringle maneuver is also regularly required during liver transplantation. This maneuver leads to temporary hepatic ischemia and may be associated with splanchnic blood flow congestion, promoting undesirable hemodynamic disturbances in some patients. Veno-venous bypass is a useful, easily performed technique that may avoid those deleterious hemodynamic effects of PTO. We tested the hypothesis that an active spleno-femoral shunt maintains hemodynamic stability and promotes complete decompression of the mesenteric bed, avoiding intestinal mucosal blood congestion, during PTO.Methods. Seven dogs (17.2 +/- 0.9 kg) were subjected to 45 minutes of hepatic ischemia during which there was an active spleno- femoral shunt. Systemic hemodynamics were evaluated through Swan-Ganz and arterial catheters. Splanchnic perfusion was assessed by portal vein blood flow and hepatic artery blood flow (PVBF and HABF, ultrasonic flowprobe), intestinal mucosal-arterial pCO(2) gradient (D(t-a)pCO(2), tonometry), and regional O-2-derived variables.Results. No significant changes in systemic and regional parameters were observed during the ischernia period. During reperfusion, a significant decrease in mean arterial pressure, PVBF, and arterial pH was observed. A significant increase in ALT and D(t-a)pCO(2) (4.8 +/- 2.5 to 18.9 +/- 3 mm Hg) was also observed following hepatic blood flow restoration.Conclusion. Spleno-femoral shunt maintains systemic hemodynamic stability, with an effective decompression of the splanchnic bed during portal triad occlusion. the deleterious hemodynamic and metabolic effects observed during reperfusion period, such as transitory hypotension, high D(t-a)pCO(2), and acidemia, were associated with an isolated hepatic ischemia-reperfusion injury, not with the blood congestion in the splanchnic bed.Universidade Federal de São Paulo, Sch Med, Div Appl Physiol, Heart Inst,InCor, São Paulo, BrazilUniversidade Federal de São Paulo, Sch Med, Div Appl Physiol, Heart Inst,InCor, São Paulo, BrazilWeb of Scienc

Gene expression in coffee

Coffee is cultivated in more than 70 countries of the intertropical belt where it has important economic, social and environmental impacts. As for many other crops, the development of molecular biology technics allowed to launch research projects for coffee analyzing gene expression. In the 90s decade, the first expression studies were performed by Northern-blot or PCR, and focused on genes coding enzymes of the main compounds (e.g., storage proteins, sugars, complex polysaccharides, caffeine and chlorogenic acids) found in green beans. Few years after, the development of 454 pyrosequencing technics generated expressed sequence tags (ESTs) obviously from beans but also from other organs (e.g., leaves and roots) of the two main cultivated coffee species, Coffea arabica and C. canephora. Together with the use of real-time quantitative PCR, these ESTs significantly raised the number of coffee gene expression studies leading to the identification of (1) key genes of biochemical pathways, (2) candidate genes involved in biotic and abiotic stresses as well as (3) molecular markers essential to assess the genetic diversity of the Coffea genus, for example. The development of more recent Illumina sequencing technology now allows large-scale transcriptome analysis in coffee plants and opens the way to analyze the effects on gene expression of complex biological processes like genotype and environment interactions, heterosis and gene regulation in polypoid context like in C. arabica. The aim of the present review is to make an extensive list of coffee genes studied and also to perform an inventory of large-scale sequencing (RNAseq) projects already done or on-going