EST is a relatively safe and effective procedure in the treatment of choledocholithiasis. The best prognostic factor is the presence of choledocholithiasis alone. Concurrent choledocholithiasis and cholecystolithiasis carry a more adverse prognosis, and in these cases cholecystectomy should be considered after EST.

Signal transduction is essential for bacteria to adapt to changing environmental conditions. Among many forms of post-translational modifications, reversible protein phosphorylation has evolved as a ubiquitous molecular mechanism of protein regulation in response to specific stimuli. The Ser/Thr protein kinase PknG modulates the fate of intracellular glutamate by controlling the phosphorylation status of the 2-oxoglutarate dehydrogenase regulator OdhI, a function that is conserved among diverse actinobacteria. PknG has a modular organization characterized by the presence of regulatory domains surrounding the catalytic domain. Here we present an investigation through in vivo experiments as well as biochemical and structural methods of the molecular bases of the regulation of PknG from C. glutamicum (CgPknG), in the light of previous knowledge available for the kinase from M. tuberculosis (MtbPknG). We found that OdhI phosphorylation by CgPknG is regulated by a conserved mechanism that depends on a C-terminal domain composed of tetratricopeptide repeats (TPR) essential for metabolic homeostasis. Furthermore, we identified a conserved structural motif that physically connects the TPR domain and a flexible N-terminal extension of the kinase that is involved in docking interactions with OdhI. Based on our results and previous reports, we propose a model in which the TPR domain of PknG couples signal detection to the specific phosphorylation of OdhI. Overall, the available data indicate that conserved PknG domains in distant actinobacteria retain their roles in kinase regulation in response to nutrient availability.IMPORTANCEBacteria control the metabolic processes by which they obtain nutrients and energy in order to adapt to the environment. In this way, the metabolic characteristics of a microorganism determine its ecological role and its usefulness in industrial processes. Here, we use genetic, biochemical, and structural approaches to study a key component in a system that regulates glutamate production in C. glutamicum, a species that is used for the industrial production of amino acids. We elucidated molecular mechanisms involved in metabolic control in C. glutamicum, which are conserved in related pathogenic bacteria. The findings have broader significance for diverse actinobacteria, including microorganisms that cause disease as well as environmental species used to produce billions of dollars of amino acids and antibiotics every year.

. (1975). Thorax, 30,[371][372][373][374][375][376][377][378][379][380][381] Myocardial ultrastructural changes during extracorporeal circulation with anoxic cardiac arrest and its prevention by coronary perfusion. Experimental study. This experimental work has been carried out with the aim of studying the ultrastructural myocardial changes caused by prolonged anoxic cardiac arrest during cardiopulmonary bypass, and their prevention by means of two different techniques of coronary perfusionsystemic-pressure continuous and low-pressure intermittent perfusion.After 30 minutes of cardiac anoxia, the ultrastructural changes of the myocardial cell were reverted to normal by coronary perfusion; when anoxic cardiac arrest was prolonged up to 60 minutes there was severe myocardial damage, with marked mitochondrial changes and dehiscence of intercalated discs, which persisted in spite of restoring coronary flow. These morphological data were in accordance with the fact that no dog which underwent anoxic cardiac arrest for 60 minutes recovered.Both intermittent and continuous coronary perfusion were effective in preventing anoxic damage; cardiac muscle cells were better preserved by low-pressure intermittent perfusion than by systemic-pressure continuous perfusion, which caused intracellular and intramitochondrial oedema.

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