Impedance cardiographic monitoring during pericardiocentesis: comparison with echocardiography

OBJECTIVE: Thoracic impedance cardiography (TIC) is a noninvasive method which has proved to be useful in monitoring the haemodynamic status of the patients. In this study, we evaluated the TIC findings in patients with pericardial effusion and cardiac tamponade. METHODS AND RESULTS: The study consisted of patients with pericardial effusion with (group A) or without (group B) cardiac tamponade (CT). The stroke volume, cardiac output and ejection fraction was measured by both echocardiography and TIC. The measurements were done at baseline in both groups and following pericardiocentesis in group A. The variables were compared by linear regression analysis, paired sample's t test and chi-square test. The study included 32 patients. Group A consisted of 16 patients and group B of 14 patients. Two patients were excluded from comparisons because of insufficient quality of the echocardiographic examination. There were no significant differences between group A and B with regard to demographic features. Both echocardiographic and TIC measurements at baseline revealed decreased cardiac output, EDV and SV in group A and EF was not different. Linear regression analysis revealed that echocardiography and TIC were in significant correlation with regard to cardiac output, enddiastolic volume, stroke volume (p < 0.01) but not ejection fraction (p = 0.8910). The correlation was also present after pericardiocentesis. CONCLUSIONS: TIC can be safely used in patients with pericardial effusion. It provides suggestive data for the diagnosis of CT and can be used as a means of monitoring the results of the pericardiocentesis.     

Coronary artery bypass surgery in patients with severe left ventricular dysfunction

Objective: The role of coronary artery bypass grafting (CABG) in patients with severe left ventricular dysfunction was evaluated. Methods: Two hundred and twelve patients (152 men, 60 women; age 35 to 82, mean 55) with ejection fraction (EF) of less than 30% underwent CABG between January 1996 and February 2001 by a single surgeon (SA). They compromised of 12% of 1759 patients operated on in this period. EF ranged from 17% to 30% (mean 25%). Preoperatively 68% had congestive heart failure and 72% had severe angina (CCS 3 or 4). A left main lesion was found in 26% of the cases. The mean number of grafts was 3.18 per patient. The left internal mammary artery (LIMA) was used on 107 patients (50.4%). Preoperative intraaortic balloon pump (IABP) was used on 32 patients (15%). Endarterectomy was performed on 53 patients (25%). The patients were followed for up to 58 months (mean 28.7). Results: Twelve patients died in hospital (5.6%). Survival was 94%, 87%, 80% and 73% at 1, 2, 3 and 4 years respectively. Among the preoperative variables survival was negatively affected by chronic renal failure, older age, congestive heart failure, elevated pulmonary artery pressure and recent myocardial infarction, by means of multivariate analysis. Preoperative IABP support improved the operative mortality significantly (P=0.002). Use of LIMA did not have any influence on survival. Conclusion: CABG on patients with poor left ventricular function: (1) Can be performed with an acceptable mortality. (2) Mid term results are encouraging. (3) Preoperative IABP support improves the chance of survival.     

Changes in bloodstream infections in HIV-positive patients in a university hospital in Spain (1995-1997).

OBJECTIVES: The Hospital Universitario Germans Trias i Pujol is a 600-bed center serving 700,000 inhabitants including 1800 patients with HIV infection in Catalonia (Spain). Highly active antiretroviral therapy (HAART) became available at the end of 1996. Thus, the period 1995 1997 was considered appropriate for evaluating possible epidemiological changes in bloodstream infections (BSI) in HIV-infected patients. METHODS: All significant bloodstream infections, including mycobacteremia and fungemia, observed in HIV-positive patients from January, 1995 to December, 1997 have been included in the study. RESULTS: One hundred and eighty six cases were evaluated, in whom a decrease in BSI was observed (68 in 1995, 86 in 1996, 32 in 1997). Over time, we observed an improvement in the immunologic situation of the patients (1995: CD4 <50/mm3 73.8% vs 1997: CD4 <50/mm3 45.5% (P=0.05)). The source of BSI was known in 80.7% of the episodes. BSI secondary to catheter and respiratory infections prevailed in 1995, whereas an increase in bacteremias related to intravenous drug use, with or without endocarditis, was seen in 1997. The most frequent isolates were Mycobacterium avium intracellulare (23) (MAI), M. tuberculosis (20), Staphylococcus aureus (20), coagulase-negative staphylococci (16), Salmonella spp. (16) and Streptococcus pneumoniae (15). In 1997, a decrease was observed in the isolation of Gram-negatives and Mycobacterium spp. with S. aureus and enterococci prevailing. CONCLUSIONS: The prevalence of bloodstream infections in HIV-positive patients has decreased since the introduction of HAART and the immunologic state has improved. Furthermore there is a trend to a decrease or disappearance of microorganisms, such as Pseudomonas spp., Mycobacterium tuberculosis, MAI or fungi related to severe immunosuppression. Lastly, bacteremia caused by the active use of intravenous drugs remains stable with the highest percentage in Spain.     

Laparoscopic Resection for Colon Cancer: Would all Patients Benefit?

Purpose This study was designed to assess whether the exclusion criteria used in the Clinical Outcomes of Surgical Therapy and Colon Cancer Laparoscopic or Open Resection trials affected the generalizability of their findings. Methods A prospective database of consecutive laparoscopic resections performed for colon cancer was reviewed. Patients were categorized into two groups: inclusion group and exclusion group, based on the selection criteria used in the Clinical Outcomes of Surgical Therapy and Colon Cancer Laparoscopic or Open Resection trials. Baseline and perioperative data were analyzed by using t-tests, Wilcoxon’s rank-sum, chi-squared, and Fisher’s exact test. Kaplan-Meier survival curves, followed by adjustment for tumor nodes metastasis stage and age utilizing a Cox proportional hazard model, were performed. Results The inclusion group had 221 patients and the exclusion group had 166 (median age and gender distribution were similar). The exclusion group had a higher conversion rate (23 vs. 11.3 percent; P = 0.0023). There was no difference in intraoperative complications (9 percent for exclusion group vs. 8.6 percent for inclusion group; P = 0.8), operative time (180 minutes for exclusion group vs.172 minutes for inclusion group; P = 0.24), or postoperative complication rates (33.7 percent for exclusion group vs. 26 percent for inclusion group; P = 0.13). No difference was detected in perioperative mortality rates, length of stay, days to diet as tolerated, and adjusted two-year survival. Conclusions No differences were found in outcomes between the two groups in terms of operative/postoperative complications, length of stay, perioperative mortality, and two-year survival. It seems that all patients with colon cancer can potentially benefit from a laparoscopic approach. Read at the meeting of The American Society of Colon and Rectal Surgeons, St. Louis, Missouri, June 2 to 6, 2007.     

Novel mode for neutrophil protease cathepsin G-mediated signaling: membrane shedding of epidermal growth factor is required for cardiomyocyte anoikis

Neutrophils are thought to orchestrate myocardial remodeling during the early progression to cardiac failure through the release of reactive oxygen species, antimicrobial peptides, and proteases. Although neutrophil activation may be beneficial at early stages of disease, excessive neutrophil infiltration can induce cardiomyocyte death and tissue damage. The neutrophil-derived serine protease cathepsin G (Cat.G) has been shown to induce neonatal rat cardiomyocyte detachment and apoptosis by anoikis. However, the involved signaling mechanisms for Cat.G are not well understood. This study identifies epidermal growth factor receptor (EGFR) transactivation as a mechanism whereby Cat.G induces signaling in cardiomyocytes. Cat.G induced a rapid and transient increase in EGFR tyrosine phosphorylation, and inhibition of EGFR kinase activity, either with AG1478 or by expression of kinase inactive EGFR mutants (EGFR-CD533), markedly attenuated EGFR downstream signaling and myocyte anoikis induced by Cat.G. Consistent with this effect of EGFR, high level expression of wild-type EGFR was sufficient to promote myocyte apoptosis. We also found that matrix metalloproteinase-dependent membrane shedding of heparin-binding EGF was involved in Cat.G signaling and that membrane type 1 matrix metalloproteinase activation may constitute a potential target that entails matrix metalloproteinase activation induced by Cat.G. The paradoxical proapoptotic effect of EGFR appeared to be dependent on protein tyrosine phosphatase SHP2 (Src homology domain 2-containing tyrosine phosphatase 2) activation and focal adhesion kinase downregulation. These results show that Cat.G-induced cardiomyocyte apoptosis involves an increase in EGFR-dependent activation of SHP2 that promotes focal adhesion kinase dephosphorylation and subsequent cardiomyocyte anoikis.     

JuSpace: A tool for spatial correlation analyses of magnetic resonance imaging data with nuclear imaging derived neurotransmitter maps

Recent studies have shown that drug‐induced spatial alteration patterns in resting state functional activity as measured using magnetic resonance imaging (rsfMRI) are associated with the distribution of specific receptor systems targeted by respective compounds. Based on this approach, we introduce a toolbox (JuSpace) allowing for cross‐modal correlation of MRI‐based measures with nuclear imaging derived estimates covering various neurotransmitter systems including dopaminergic, serotonergic, noradrenergic, and GABAergic (gamma‐aminobutric acid) neurotransmission. We apply JuSpace to two datasets covering Parkinson''s disease patients (PD) and risperidone‐induced changes in rsfMRI and cerebral blood flow (CBF). Consistently with the predominant neurodegeneration of dopaminergic and serotonergic system in PD, we find significant spatial associations between rsfMRI activity alterations in PD and dopaminergic (D2) and serotonergic systems (5‐HT1b). Risperidone induced CBF alterations were correlated with its main targets in serotonergic and dopaminergic systems. JuSpace provides a biologically meaningful framework for linking neuroimaging to underlying neurotransmitter information.     

Electrochemical sensory detection of Sus scrofa mtDNA for food adulteration using hybrid ferrocenylnaphthalene diimide intercalator as a hybridization indicator

In this study, an electrochemical DNA biosensor was developed based on the fabrication of silicon nanowires/platinum nanoparticles (SiNWs/PtNPs) on a screen-printed carbon electrode (SPCE) for the detection of Sus scrofa mitochondrial DNA (mtDNA) in food utilizing a new hybrid indicator, ferrocenylnaphthalene diimide (FND). The morphology and elemental composition of the SiNWs/PtNPs-modified SPCE was analyzed by field emission scanning electron microscopy (FESEM) combined with energy dispersive X-ray spectroscopy (EDX). Cyclic voltammetry (CV) was used to study the electrical contact between the PtNPs and the screen-printed working electrode through SiNWs, while electrochemical impedance spectroscopy (EIS) was used to measure the charge transfer resistance of the modified electrode. The results clearly showed that the SiNWs/PtNPs were successfully coated onto the electrode and the effective surface area for the SiNWs/PtNPs-modified SPCE was increased 16.8 times as compared with that of the bare SPCE. Differential pulse voltammetry used for the detection of porcine DNA with FND as an intercalator confirmed its specific binding to the double-stranded DNA (dsDNA) sequences. The developed biosensor showed a selective response towards complementary target DNA and was able to distinguish non-complementary and mismatched DNA oligonucleotides. The SiNWs/PtNPs-modified SPCE that was fortified with DNA hybridization demonstrated good linearity in the range of 3 × 10⁻⁹ M to 3 × 10⁻⁵ M (R² = 0.96) with a detection limit of 2.4 × 10⁻⁹ M. A cross-reactivity study against various types of meat and processed food showed good reliability for porcine samples.

An electrochemical DNA biosensor was developed based on the fabrication of silicon nanowires/platinum nanoparticles on a screen-printed carbon electrode for the detection of Sus scrofa mitochondrial DNA in food.