Induction of anesthesia in coronary artery bypass graft surgery: the hemodynamic and analgesic effects of ketamine

OBJECTIVE: The aim of this prospective, randomized study was to evaluate the hemodynamic and analgesic effects of ketamine by comparing it with propofol starting at the induction of anesthesia until the end of sternotomy in patients undergoing coronary artery bypass grafting surgery. INTRODUCTION: Anesthetic induction and maintenance may induce myocardial ischemia in patients with coronary artery disease. A primary goal in the anesthesia of patients undergoing coronary artery bypass grafting surgery is both the attenuation of sympathetic responses to noxious stimuli and the prevention of hypotension. METHODS: Thirty patients undergoing coronary artery bypass grafting surgery were randomized to receive either ketamine 2 mg.kg-1 (Group K) or propofol 0.5 mg.kg-1 (Group P) during induction of anesthesia. Patients also received standardized doses of midazolam, fentanyl, and rocuronium in the induction sequence. The duration of anesthesia from induction to skin incision and sternotomy, as well as the supplemental doses of fentanyl and sevoflurane, were recorded. Heart rate, mean arterial pressure, central venous pressure, pulmonary arterial pressure, pulmonary capillary wedge pressure, cardiac index, systemic and pulmonary vascular resistance indices, stroke work index, and left and right ventricular stroke work indices were obtained before induction of anesthesia; one minute after induction; one, three, five, and ten minutes after intubation; one minute after skin incision; and at one minute after sternotomy. RESULTS: There were significant changes in the measured and calculated hemodynamic variables when compared to their values before induction. One minute after induction, mean arterial pressure and the systemic vascular resistance index decreased significantly in group P (

Specific nuclear envelope transmembrane proteins can promote the location of chromosomes to and from the nuclear periphery

BACKGROUND: Different cell types have distinctive patterns of chromosome positioning in the nucleus. Although ectopic affinity-tethering of specific loci can be used to relocate chromosomes to the nuclear periphery, endogenous nuclear envelope proteins that control such a mechanism in mammalian cells have yet to be widely identified. RESULTS: To search for such proteins twenty three nuclear envelope transmembrane proteins were screened for their ability to promote peripheral localization of human chromosomes in HT1080 fibroblasts. Five of these proteins had strong effects on chromosome 5, but individual proteins affected different subsets of chromosomes. The repositioning effects were reversible and the proteins with effects all exhibited highly tissue-restricted patterns of expression. Depletion of two nuclear envelope transmembrane proteins that were preferentially expressed in liver each reduced the normal peripheral positioning of chromosome 5 in liver cells. CONCLUSIONS: The discovery of nuclear envelope transmembrane proteins that can modulate chromosome position and have restricted patterns of expression may enable dissection of the functional relevance of tissue-specific patterns of radial chromosome positioning.Publisher PDFPeer reviewe

Comparison of prognostic scores and surgical approaches to treat spinal metastatic tumors: A review of 57 cases

Surgical treatment of metastatic spinal cord compression with or without neural deficit is controversial. Karnofsky and Tokuhashi scores have been proposed for prognosis of spinal metastasis. Here, we conducted a retrospective analysis of Karnofsky and modified Tokuhashi scores in 57 consecutive patients undergoing surgery for secondary spinal metastases to evaluate the value of these scores in aiding decision making for surgery. Comparison of preoperative Karnofsky and modified Tokuhashi scores with the type of the surgical approach for each patient revealed that both scores not only reliably estimate life expectancy, but also objectively improved surgical decisions. When the general status of the patient is poor (i.e., Karnofsky score less than 40% or modified Tokuhashi score of 5 or greater), palliative treatments and radiotherapy, rather than surgery, should be considered

The nuclear envelope proteome differs notably between tissues

One hypothesis to explain how mutations in the same nuclear envelope proteins yield pathologies focused in distinct tissues is that as yet unidentified tissue-specific partners mediate the disease pathologies. The nuclear envelope proteome was recently determined from leukocytes and muscle. Here the same methodology is applied to liver and a direct comparison of the liver, muscle and leukocyte data sets is presented. At least 74 novel transmembrane proteins identified in these studies have been directly confirmed at the nuclear envelope. Within this set, RT-PCR, western blot and staining of tissue cryosections confirms that the protein complement of the nuclear envelope is clearly distinct from one tissue to another. Bioinformatics reveals similar divergence between tissues across the larger data sets. For proteins acting in complexes according to interactome data, the whole complex often exhibited the same tissue-specificity. Other tissue-specific nuclear envelope proteins identified were known proteins with functions in signaling and gene regulation. The high tissue specificity in the nuclear envelope likely underlies the complex disease pathologies and argues that all organelle proteomes warrant re-examination in multiple tissues