Israel Medical Association Journal

Background: Left main coronary artery disease is considered a surgical indication in most centers. However, in some cases prohibited from surgery or in patients with prior bypass grafting, there is a need for percutaneous coronary intervention in LMCA[1] disease scenarios.

Objectives: To assess the clinical outcomes among patients undergoing stent-based LMCA angioplasty.

Methods: We identified 34 consecutive patients who underwent PCI[2] in LMCA at our institution. Procedural data and clinical outcomes were obtained for all patients.

Results: The mean age was 71 ± 12 years. There were 27 elective and 7 emergent procedures performed on 23 “protected” LMCA and 11 “unprotected” LMCA. In emergent procedures, the prevalence of cardiogenic shock (29% vs. 0%, P = 0.04) in patients with prior coronary bypass (29% vs. 8.5%, P = 0.007) was significantly higher compared to elective cases. Procedural success in emergent procedures was significantly lower than in elective procedures (71 vs. 100%, P = 0.04). In emergent versus elective procedures, the in-hospital mortality rate was higher (43 vs. 0%, P = 0.006). The rate of cumulative major adverse cardiac events at 1 and 6 months was 43% and 71% in emergent cases versus 0% and 33% in elective cases (P < 0.05 for both comparisons). In patients with “unprotected” LMCA the overall major cardiac events at 1 month was higher compared to “protected” LMCA patients (27 vs. 0%, P = 0.02). Multivariate analysis revealed emergent procedure as an independent predictor for mortality and adverse cardiac events (odds ratio 6.7; 95% confidence interval 1.2–36; P = 0.02).

Conclusions: Percutaneous interventions in LMCA are feasible and relatively safe in carefully selected cases. Procedural outcomes and clinical prognosis is highly dependent on the nature of disease prior to angioplasty (e.g., elective vs. emergent procedure) as well as on protection of the LMCA by patent grafts.

Between the 1960s and 1980s, the main focus of biological research was nucleic acids and the translation of the coded information into proteins. Protein degradation was a neglected area and regarded by many as a scavenger, non-specific and end process. While it was known that proteins are turning over, the large extent and high specificity of the process - where distinct proteins have half-lives that range from a few minutes to several days - have not been appreciated. The discovery of the lysosome by Dr. Christian de Duve did not change this view significantly, as this organelle is involved mostly in the degradation of extra- and not intracellular proteins, and it was clear that lysosomal proteases, similar to those of the gastrointestinal tract, cannot be substrate specific. The discovery of the complex cascade of the ubiquitin pathway has changed this view dramatically. It is now clear that degradation of cellular proteins is a highly complex, temporally controlled, and tightly regulated process that plays major roles in a broad array of basic pathways during cell life and death. With the multitude of substrates targeted and processes involved, it is not surprising that aberrations in the pathway have been recently implicated in the pathogenesis of many diseases, certain malignancies and neurodegeneration among them. Degradation of a protein via the ubiquitin pathway involves two successive steps: a) conjugation of multiple ubiquitin moieties to the substrate, and b) degradation of the tagged protein by the downstream 263 proteasome complex with release of free and re-utilizable ubiquitin. Despite intensive research, the unknown still exceeds what we currently know on intracellular protein degradation and major key problems remain unsolved. Among these are the modes of specific and timed recognition of the myriad substrates of the system and the nature of the mechanisms that underlie aberrations in the system and pathogenesis of diseases.

Objective: To describe the epidemiology of ceftazidime-resistant K. pneumoniae in our medical center, as representing the situation in tertiary care hospitals in Israel.

Methods: We vigorously restricted the use of ceftazidime in the ICU and enforced barrier precautions. The susceptibility rate of K. pneumoniae was surveyed in the ICU and throughout the hospital before and after the intervention in the ICU.

Results: Following the intervention, the susceptibility rate of K. pneumoniae increased from 11% (3/28) to 47% (14/30) (P0.01) among ICU isolates, from 55% (154/280) to 62% (175/281) (P=0.08) among total hospital isolates, and from 61% (50/82) to 74% (84/113) (P0.05) among total hospital blood isolates, although no additional control measures were employed outside the ICU.

Conclusions: The epidemiology of ceftazidime-resistant K. pneumoniae in our medical center is similar to that reported from other centers around the world. Early awareness to the emergence of this resistance, identification of the source of the epidemic, and prompt action at the putative source site may reduce the rate of acquisition and spread of such resistance inside and outside of the source unit.

Background: Tumor necrosis factor is associated with various local and systemic inflammatory sequelae following snakebite. Xanthine oxidase is a principal mediator of remote tissue injury (e.g., lungs, heart, liver).

Objective: To investigate in a snakebite-like animal model the as yet unexplored role of TNF and XO in mediating organ damage following snakebite.

Methods: Sprague-Dawley rats were injected intramuscularly with a non-lethal 500 g/kg dose of Vipera aspis venom (n=10) or saline (n=10). Blood pressure and heart rate were continuously monitored, TNF- was measured in the blood, and total XO + xanthine dehydrogenase activity was assessed in various tissues. Lung histology and permeability indices were analyzed.

Results: Venom injection caused a significant (P0.05) reduction in both heart rate and invasive arterial pressure. The blood circulating TNF levels were significantly higher in the intoxicated group (P0.05 vs. saline group), with changes seen at 30 minutes from intoxication in both groups. Total XO + XDH activity in the kidney, lung and liver of the venom-injected group was significantly (P0.05) higher than in the saline group, while the activity in the heart was similar.

Conclusions: The mediation of remote organ and hemodynamic changes following intramuscular injection of a non-lethal dose of Vipera aspis venom can be attributed partly to TNF and partly to XO. More research is needed to better understand the role of either compound and the time frame of their activity before specific antagonists can be introduced for snakebite management.