Guidelines surrounding the use of implantable cardioverter-defibrillator (ICD) for primary prevention of sudden cardiac death (SCD) in patients diagnosed with heart failure have been established for many years. We suspected discordance between Canadian Cardiovascular Society’s recommendations and current clinical practice. Our goal was to establish the difference between current guidelines and clinical practice as well as factors that significantly influence referral for an ICD. Our perception was that female gender was a factor of non-adherence to ICD guidelines. This retrospective study included 903 consecutive patients that were followed by cardiologists in a specialized heart function clinic. Electronic medical record (Vision C+) collected data from patients seen between May 2005 and February 2017. Patients had to have a documented left ventricular ejection fraction of 35% or less, persistent for at least 90 days. All patients fulfilling these criteria were included except patients in New York Heart Association functional class 4. We described the use of ICD within our group of patients potentially eligible for ICD in primary prevention of SCD. Available variables such as age, sex, medication and comorbidities were analyzed. Of our 903 patients group, 195 (21,6%) were women. Mean age was 71,9 ± 12,5 years. ICD was implanted in 367 (40,6%) patients. CAD was labeled has the cause of HF in 607 (67,2%) of patients. In a multivariate analysis, factors such as age (OR=1,03, p < 0,001), female sex (OR=1,6, p=0,011) and diagnostic of cognitive impairment (OR=3,45, p=0,004) were showed to negatively influence the prescription of an ICD. The prescription of an ICD should be approached individually according to the age, comorbidities and wishes of each patient. The present study suggests that women, independently of age and comorbidities, were significantly less likely than men to receive an ICD. Our group included only 21,6% of women which can possibly be a source a bias. We cannot know for sure if the difference noted is related to wishes and beliefs in our group or if there really is a sex bias within clinical practice. This concern would benefit further evaluation in future studies.

Brain Natriuretic Peptide (BNP) reflects the left ventricular pressure and is known to be elevated in diastolic dysfunction. The objective of our study was to compare the BNP levels in two groups of patients with different severity of diastolic dysfunction. We measured BNP, diastolic dysfunction and clinical parameters in 121 patients (mean age: 65.1 ± 8.4 years; 78 males, 43 females) enrolled at the cardiology laboratory and rehabilitation clinic, at the Sherbrooke University Hospital. We divided the patients in two groups according to the severity of the diastolic dysfunction: mild (group 1: E/A < 1 at rest), and moderate (group 2: E/A>1 at rest, reverse Valsalva or an abnormal tissue doppler with an E/E'> 8). Patients in group 1 had a lower but not significant BNP level of 28.9 ± 26.0 pg/mL, n = 64, in comparison to 43,9 ± 45,4 pg/mL, n = 57 for group 2 (p = 0.136). Patients with elevated LV end diastolic pressure, defined as E/E' > 15 (n = 12) had the highest BNP levels (54.1 ± 50.5 pg/mL), patient with E/E' between 8 and 15 (n = 80) had a mean BNP level of 37.6 ± 37.6 pg/mL and those with E/E' < 8 (n = 29) had a mean BNP level of 24.0 ± 24.6 pg/mL (p <0.05). The log-transformed BNP correlated significantly with E/E'septal (r = 0.312, p = 0.01). Multivariate regression analysis demonstrated a significant correlation of log-transformed BNP with diastolic dysfunction (p = 0.013) regardless of age, sex and creatinine clearance. The area under the receiver-operating characteristic curve for BNP to discriminate between the two groups was 0.58 (95% CI, 0.48-0.68; p = 0.136). BNP levels show a relationship with diastolic dysfunction characteristics but does not seem to discriminate between mild and moderate diastolic dysfunction. A probable reason for this result is that BNP is not sensitive to detect diastolic dysfunction with normal filling pressure.

Background The Siemens ADVIA Centaur® CP Immunoassay system is a benchtop system that uses the same reagents, calibrators, controls and ancillaries as the larger ADVIA Centaur Immunoassay system. The ADVIA Centaur hepatitis assays (aHAVM, HAVT, aHBcM, HBcT, aHBs, HBs, HBsAg Confirmatory and aHCV)* were evaluated at three sites each for precision, patient sample concordance and patient sample correlation. Each assay was evaluated at the Siemens Tarrytown laboratory and at two external sites. The aHAVM and HAVT assays were evaluated at Collaborative Research for Effective Diagnostics in Sherbrooke, Quebec and at Specialty Laboratories in Valencia, California. The other assays were evaluated at the University of Miami and the University of Texas.

We have treated Jurkat T lymphocytes with a concentration (160 nM) of phorbol myristyl acetate (PMA) that down-regulates conventional and novel protein kinase C (PKC) isozymes and we have investigated the effects on Ca2+ signaling and protein tyrosine phosphorylation using mAb (C305) directed against the beta-subunit of the Ti heterodimer or the epsilon/delta-component of the CD3 complex (mAb Leu 4 or OKT 3). The levels of expression of PKC alpha, betaI, betaII, and delta were reduced by 90% or more in PMA-treated cells, whereas the expression of PKCtheta decreased by approximately 30%. In contrast, the chronic treatment with PMA increased the expression of PKCepsilon and PKCzeta. There was a lack of Ca2+ response and myo-inositol trisphosphate (IP3) production in PMA-treated cells when they were exposed to mAb Leu 4 but the cells responded to mAb C305. The treatment with PMA did not affect the surface expression of Ti or CD3. The overall levels of tyrosine-phosphorylated proteins were markedly reduced in PMA-treated cells. We investigated whether these observations were related to defects in signal transduction related to protein tyrosine kinase (PTK) of the src and syk families. The electrophoretic mobilities of p59(fyn) or ZAP-70 were not changed in PMA-treated cells but p56(Ick) migrated as a large band of M(r) 60-62 kDa. The decreased mobility of p56(Ick) was related to a state of hyperphosphorylation. The activity of modified p56(Ick) was not up-regulated in activated Jurkat cells. Our data suggest that clonotypic Ti can trigger Ca2+ mobilization independently of conventional PKC isoforms. Our observations further suggest that conventional PKC isoforms are involved early in the cascade of events associated with Jurkat T lymphocyte activation.

Spatial analyses of the distribution of Ca2+ in resting-and activated T and B lymphocytes have shown that the bulk of increased [Ca2+](i) appears to be associated with the nuclear region. These observations suggest that Ca2+ is released from the perinuclear space or that it diffuses to the nucleoplasm, or both. We have used laser scanning confocal microscopy to assess whether cytoplasmic, diffusion of Ca2+ could contribute to the rise in nuclear Ca2+. We found that the activation of individual Jurkat cells by use of an anti-Ti (beta-subunit) mAb induced a nucleus-associated increase in [Ca2+](i). In cells loaded with the InsP3 receptor antagonist heparin, the nuclear Ca2+ response was abolished but not the response to thapsigargin. Evidence for a cytoplasmic Ca2+ response was obtained by loading Jurkat cells with a cytoplasm-restricted Ca2+ probe (Calcium Green-1-Dextran). These observations suggested that a process of diffu sion of cytoplasmic Ca2+ contributed to the rise of nuclear Ca2+ in Jurkat T cells. This interpretation was supported by the findings (1) that rapid scanning of thapsigargin-released Ca2+ showed an inverse relationship between the levels of cytoplasmic and nuclear Ca2+ and (2) that modulation of the external concentration of Ca2+ in thapsigargin-treated Jurkat cells showed a time-dependent decrease of fluorescence from the nucleoplasm that was reversed by raising the concentration of external Ca2+. We conclude that Ca2+ can rapidly diffuse between the cytoplasm and the nucleoplasm in activated Jurkat T lymphocytes and that hydrophilic Ca2+ probes largely partition to the nucleoplasm, thus giving rise to distorted nucleus-to-cytoplasm fluorescence ratios.

Staurosporine (Stp) is an inhibitor of protein kinase C (PKC) that has been used to address the role of this enzyme in a variety of cells. However, Stp can also inhibit protein tyrosine kinases (PTK). We have investigated the effects of Stp on the InsP3- (using mAb C305 directed against the β chain of the T cell receptor (TcR)/CD3 complex) and the thapsigargin (Tg)-dependent release and influx of Ca2+ in human (Jurkat) T cells. The addition of Stp (200 nM) during the sustained phase of the TcR-dependent Ca2+ response resulted in a rapid inhibition of the influx of Ca2+ that was not seen when Ca2+ mobilization was triggered by Tg (1 μM). When the cells were preincubated with Stp (200 nM), there was an inhibition of the mAb C305- but not the Tg-dependent Ca2+ response. The effect of Stp was not the result of the inhibition of PKC as shown by down-regulation of PKC and with the use of the specific PKC inhibitor bis-indolyl maleimide GF 109203X. The effect of Stp on the entry of Ca2+ in activated (mAb C305) Jurkat lymphocytes was dose-related and was not the result of a direct inhibition of plasma membrane Ca2+ channels based on an absence of effect on the Tg-dependent entry of Ca2+ and the use of Ca2+ channel blockers (econazole and Ni2+). These blockers terminated the influx of Ca2+ but the Tg-sensitive Ca2+ reserves were not refilled in marked contrast to the effect of Stp. Quantification of InsP3 revealed that the addition of Stp resulted in an approximate 40% reduction in mAb C305-activated Jurkat cells. The effects of Stp can be explained as follows. Stp decreases the mAb C305-induced production of InsP3 by inhibiting the TcR/CD3-dependent activation of PTK associated with the stimulation of phospholipase C-γ1. A decrease in [InsP3] without a return to baseline is sufficient to close the InsP3 Ca2+ channel, endoplasmic Ca2+ ATPases use the incoming Ca2+ to refill the Ca2+ pools and that terminates the capacitative entry of Ca2+. A simple kinetic model reproduced the experimental data.