Determination, validation and standardization of a CMV DNA cut-off value in plasma for preemptive treatment of CMV infection in solid organ transplant recipients at lower risk for CMV infection

BACKGROUND

Valganciclovir preemptive therapy guided by the viral load is the current strategy recommended for preventing CMV disease in CMV-seropositive Solid Organ Transplant Recipients (SOTR) at lower risk for developing CMV infection. However, universal viral load cut-off has not been established for initiating therapy.

OBJECTIVES

Our goal was to define and validate a standardized cut-off determined in plasma by real-time PCR assay for initiating preemptive therapy in this population.

STUDY DESIGN

A prospective cohort study of consecutive cases of CMV-seropositive SOTR was carried out. The cut-off value was determined in a derivation cohort and was validated in the validation cohort. Viral loads were determined using the Quant CMV LightCycler 2.0 real-time PCR System (Roche Applied Science) and results were standardized using the WHO International Standard for human CMV.

RESULTS

A viral load of 3983 IU/ml (2600 copies/ml) was established as the optimal cut-off for initiating preemptive therapy in a cohort of 141 patients with 982 tests and validated in a cohort of 252 recipients with a total of 2022 test. This cut-off had a 99.6% NPV indicating that the great majority of patients at lower risk will not develop CMV disease without specific antiviral therapy. The high sensitivity and specificity (89.9% and 88.9%, respectively) and the relatively small numbers of patients with CMV disease confirm that real-time PCR was optimal.

CONCLUSIONS

We have established a cut-off viral load for starting preemptive therapy for CMV-seropositive SOT recipients. Our results emphasized the importance of a mandatory follow-up protocol for CMV-seropositive patients receiving preemptive treatment.

Differences between HIV-infected and uninfected adults in the contributions of smoking, diabetes and hypertension to acute coronary syndrome: two parallel case-control studies

OBJECTIVES

The aim of the study was to assess the separate contributions of smoking, diabetes and hypertension to acute coronary syndrome (ACS) in HIV-infected adults relative to uninfected adults.

METHODS

Two parallel case-control studies were carried out. In the first study, HIV-positive adults diagnosed with ACS between 1997 and 2009 (HIV+/ACS) were matched for age, gender and known duration of HIV infection with HIV-positive adults without ACS (HIV+/noACS), each individual in the HIV+/ACS group being matched with three individuals in the HIV+/noACS group. In the second study, each individual in the HIV+/ACS group in the first study was matched for age, gender and calendar date of ACS diagnosis with three HIV-negative individuals diagnosed with ACS between 1997 and 2009 (HIV-/ACS). Each individual in the HIV-/ACS group was then matched for age and gender with an HIV-negative adult without ACS (HIV-/noACS). After matching, the ratio of numbers of individuals in the HIV+/ACS, HIV+/noACS, HIV-/ACS and HIV-/noACS groups was therefore 1 : 3 : 3 : 3, respectively. We performed logistic regression analyses to identify risk factors for ACS in each case-control study and calculated population attributable risks (PARs) for smoking, diabetes and hypertension in HIV-positive and HIV-negative individuals.

RESULTS

There were 57 subjects in the HIV+/ACS group, 173 in the HIV+/noACS group, 168 in the HIV-/ACS group, and 171 in the HIV-/noACS group. Independent risk factors for ACS were smoking [odds ratio (OR) 4.091; 95% confidence interval (CI) 2.086-8.438; P < 0.0001] and a family history of cardiovascular disease (OR 7.676; 95% CI 1.976-32.168; P = 0.0003) in HIV-positive subjects, and smoking (OR 4.310; 95% CI 2.425-7.853; P < 0.0001), diabetes (OR 5.778; 95% CI 2.393-15.422; P = 0.0002) and hypertension (OR 6.589; 95% CI 3.554-12.700; P < 0.0001) in HIV-negative subjects. PARs for smoking, diabetes and hypertension were 54.35 and 30.58, 6.57 and 17.24, and 9.07 and 38.81% in HIV-positive and HIV-negative individuals, respectively.

CONCLUSIONS

The contribution of smoking to ACS in HIV-positive adults was generally greater than the contributions of diabetes and hypertension, and was almost twice as high as that in HIV-negative adults. Development of effective smoking cessation strategies should be prioritized to prevent cardiovascular disease in HIV-positive adults.

Specific and non-overlapping functions of testosterone and 11-ketotestosterone in the regulation of professional phagocyte responses in the teleost fish gilthead seabream

Sex hormones, both estrogens and androgens, have a strong impact on immunity in mammals. In fish, the role of androgens in immunity has received little attention and contradictory conclusions have been obtained. However, it is well known that sex steroids are involved in fish growth, osmoregulation and gonad remodelation. In this study, we examine the in vitro effects of testosterone and 11-ketotestosterone, the two main fish androgens, on the professional phagocytes of the teleost fish gilthead seabream (Sparus aurata L.). Although both testosterone and 11-ketotestosterone failed to modulate the respiratory burst of seabream phagocytes, testosterone but not 11-ketotestosterone was able to increase the phagocytic ability of non-activated phagocytes. Curiously, 11-ketotestosterone was more powerful than testosterone at inducing the expression of its own receptor, namely androgen receptor b (ARb), in acidophilic granulocytes (AGs), but none of them affected the basal ARb expression levels in macrophages (MØ). Furthermore, although physiological concentrations of testosterone exerted a pro-inflammatory effect on both AGs and MØs, 11-ketotestosterone showed an anti-inflammatory effect in AGs and a strong pro-inflammatory effect in MØs. Interestingly, both androgens modulated the expression of toll-like receptors in these two immune cell types, suggesting that androgens might regulate the sensitivity of phagocytes to pathogens and damage signals. Testosterone and 11-ketotestosterone have a competitive effect, at least, on the modulation of the expression of some genes. Therefore, our results show for the first time a non-overlapping role for testosterone and 11-ketotestosterone in the regulation of professional phagocyte functions in fish.

Unexpected severity of cases of influenza B infection in patients that required hospitalization during the first postpandemic wave

OBJECTIVES

After the last pandemic the knowledge regarding influenza A infection has improved however, the outcomes of influenza B infection remain poorly studied. The aim of this study was to compare the features of influenza B versus influenza A(H1N1)pdm09 infections during the 2010-2011 epidemic-season.

METHODS

A prospective, observational-cohort of adults with laboratory-confirmed influenza infection during the 2010-2011 epidemic-season was studied

RESULTS

Fifty cases of influenza B and 80 of influenza A(H1N1)pdm09 infection were enrolled. Among patients with influenza B, the median age was 34 years-old (23-64), 30% pregnant, 24% obese, 34% transplant recipients and 14% with bacterial co-infection. Twenty-eight percent of patients had pneumonia with alveolar localized pattern and five (10%) died. Pneumonia was associated with delayed antiviral therapy, older age, higher Charlson score, invasive mechanical ventilation and bacterial co-infection. Obesity and pregnancy were not associated with complicated influenza B infection. The proportion of pneumonia, admission to the ICU and mortality did not differ between cases of influenza A(H1N1)pdm09 and influenza B infection.

CONCLUSIONS

Influenza B infection causes severe infection and it is associated with pneumonia or death, similar to influenza A(H1N1)pdm09 infection. Rapid diagnosis and early antiviral therapy are necessary for managing influenza pneumonia during epidemic periods.

Effect of orally-administered Lactobacillus plantarum LPLM-O1 strain in an immunosuppressed mouse model of urinary tract infection

Urinary tract infections (UTIs) affect both healthy and immunocompromised people, and they are treated with antibiotics. However, the high recurrence of UTIs obliges the use of natural mechanisms to regulate the normal microbiota through the use of e.g. lactic acid bacteria. In order to induce a UTI, 20 µl of the Escherichia coli (Ec-01) strain, in doses of 2.7×107 cfu/ml, was inoculated by way of the urethra in female Balb/c mice, all of them immunosuppressed with dexamethasone (10 mg/kg). Lactobacillus plantarum LPLM-O1 was used as a treatment, in daily doses of 1×107 cfu/ml, which were orally administered for seven days before the infection (preventive) or alongside the infection for seven days (curative). The oral administration of LPLM-O1 did not cause any adverse effects when used in an immunosuppressed animal model. It was observed that, when used as a preventive measure, LPLM-O1 induces a decrease in the infection, in the concentration of urinary leukocytes, and in the bacterial load. This study proposes the use of this lactic bacterium as a probiotic.

Comparison of fluid compartments and fluid responsiveness in septic and non-septic patients

Our objective was to study the response to a fluid load in patients with and without septic shock, the relationship between the response and baseline fluid distributions and the ratios of the various compartments. A total of 18 patients with septic shock and 14 control patients without pathologies that increase capillary permeability were evaluated prospectively. We used transpulmonary thermodilution to measure the extravascular lung water index, intrathoracic blood volume index and pulmonary blood volume. For the measurement of the initial distribution volume of glucose, plasma volume and extracellular water we used dilutions of glucose, indocyanine green and sinistrin respectively. Transpulmonary thermodilution and dilutions of glucose were repeated 75 minutes after the beginning of the fluid load. The patients in the septic group had higher volumes of extracellular water (median 295 vs. 234 ml/kg, P < 0.001), lower intrathoracic blood volume index (median 894 vs. 1157 ml/m2, P < 0.003), higher pulmonary permeability ratios (extravascular lung water/pulmonary blood volume) (P < 0.003) and higher systemic permeability ratios (interstitial/plasma volume) (P < 0.04). The intrathoracic blood volume index increase after fluid loading was lower in the septic group (10 vs. 145 ml/m2). The pulmonary permeability ratios did not correlate with the systemic permeability ratios, and in the septic group, the percentage volume retained in the intrathoracic blood volumes after fluid loading did not correlate with the systemic permeability ratios. Septic shock can cause a redistribution of fluids. Fluid administration in these patients produced a minimal increase in intrathoracic blood volume, and the percentage of volume retained in this space was not correlated with the interstitial/plasma volume ratio.

[Foreseeable variation in parameters measured at implant and follow-up of permanent pacemaker active fixation electrodes]

OBJECTIVES

To analyze the variations in the parameters relative to active fixation electrodes at the time of implantation and over subsequent follow-up during 6 months of the acute phase of implantation.

DESIGN

A descriptive, analytical, prospective, observational cohort study was made of consecutive cases over a period of 8 months (April-December 2010).

SETTING

Pacing unit of an Intensive Care Unit.

PATIENTS OR PARTICIPANTS

Patients undergoing permanent pacemaker implantation with active fixation electrodes, implanted in both atrium and ventricle, Interventions: Measurement of variables described with a threshold analyzer during electrode fixation and at different times during the study, Main compared variables: threshold, impedance and intrinsic activity (both atrial and ventricular) before and after fixation, at 48 hours, at one month and 6 months, Comparisons were made using the Student t-test for paired data, assuming significance for p<0,05, and ANOVA to analyze the successive changes over ambulatory follow-up.

RESULTS

We analyzed 40 patients, with 19 atrial and 40 ventricular electrodes, In fixation, the electrodes showed significant variation in the impedance values of the atrial lead (1,188,53 ± 397,26 vs 610,69 ± 326,30 ohms, p<0,0001) and ventricular lead (1,512,93 ± 718,07 vs 768,80 ± 224,90 ohms, p>0,0001), In the first 48 hours it was coupled with a decrease in ventricular (0,86 ± 0,35 vs 0,48 ± 0,23 volts, p = 0,0001) and atrial pacing threshold (1,10 ± 0,39 vs 0,43 ± 0,23 volts, p = 0,0003), and p-wave sensing (3,61 ± 2,25 vs 2,32 ± 1,09 mV, p = 0,0463), Over follow-up we found the parameters to be stable, with no significant changes.

CONCLUSIONS

After active lead fixation, a fall in impedance of the antrial and ventricular is expected, Over the next 48 hours improvement in atrial and ventricular threshold may occur, in contrast to the sensitivity of the intrinsic activity, which reached significance at the P wave measured after 48 hours, These values stabilize over patient follow-up and do not differ significantly in the studied acute patient course.

Clinical presentation of acute coronary syndrome in HIV infected adults: a retrospective analysis of a prospectively collected cohort

OBJECTIVES

To compare clinical presentation and short-term prognosis of acute coronary syndrome (ACS) in HIV-infected and uninfected adults.

DESIGN

Retrospective analysis of a prospectively collected cohort.

METHODS

HIV-infected patients with myocardial infarction or unstable angina were identified by clinical history and specific characteristics of HIV infection were consecutively registered. Surviving patients were followed for at least one month after discharge. Risk factors for cardiovascular disease, clinical symptoms at admission, type of ACS, delivery of care, and factors associated with prognosis were compared between HIV-infected and uninfected adults.

RESULTS

Among 627 patients included, 44 (7%) were HIV-infected patients. HIV-infected patients were younger, more frequently men, and had higher prevalence of cardiovascular risk factors than uninfected patients. HIV-infected patients persisted frequently with less pain at Emergency Department (ED) (34% vs 82%, P<0.001) and complained of dyspnea (2% vs 15%, P<0.05) persisted in respect to HIV-uninfected patients. ST-elevation myocardial infarction was the most frequent ACS in HIV-infected patients (59% vs 24%) whereas non-ST-elevation myocardial infarction (23% vs 38%) and unstable angina (18% vs 38%) were the predominant ones in uninfected patients (P<0.001). Catheterism was performed more commonly in HIV-infected patients (75% vs 62%, P<0.01) and similarly admitted in the coronary care unit (38% vs 41%, P=0.81). The evolution was similar in both groups. When HIV-infected patients were matched by age and sex with a subgroup of 88 HIV-uninfected patients, most of the differences disappeared.

CONCLUSIONS

HIV-infected adults presenting with ACS are younger and have fewer symptoms than uninfected. Despite having a more established disease, short-term prognosis is similar.

Analysis of the grafting process of PVP on a silicon surface by AFM and contact angle

Silicon wafers have been silylated with VTMS (vinyltrimethoxysilane) and hydrolyzed. Subsequently, PVP (polyvinyl pyrrolidone) was grafted onto the silylated surface by two different techniques: the grafting-through (GT) and the grafting-onto techniques (GO). The measurement of contact angles along with the topography analysis by atomic force microscopy (AFM) has allowed monitoring the different stages of the process and the temporal evolution of polymer grafting. The results have demonstrated the feasibility of both methods of grafting but have shown that the GT method gives a higher density of polymer-grafted chains. The AFM technique in adequate liquid environments has been proven to permit the surface density of chains to be distinguished by both methods and to estimate the length of the resulting PVP chains.

Association of Rex-1 to target genes supports its interaction with Polycomb function

Rex-1/Zfp42 displays a remarkably restricted pattern of expression in preimplantation embryos, primary spermatocytes, and undifferentiated mouse embryonic stem (ES) cells and is frequently used as a marker gene for pluripotent stem cells. To understand the role of Rex-1 in selfrenewal and pluripotency, we used Rex-1 association as a measure to identify potential target genes, and carried out chromatin-immunoprecipitation assays in combination with gene specific primers to identify genomic targets Rex-1 associates with. We find association of Rex-1 to several genes described previously as bivalently marked regulators of differentiation and development, whose repression in mouse embryonic stem (ES) cells is Polycomb Group-mediated, and controlled directly by Ring1A/B. To substantiate the hypothesis that Rex-1 contributes to gene regulation by PcG, we demonstrate interactions of Rex-1 and YY2 (a close relative of YY1) with Ring1 proteins and the PcG-associated proteins RYBP and YAF2, in line with interactions reported previously for YY1. We also demonstrate the presence of Rex-1 protein in both trophectoderm and Inner Cell Mass of the mouse blastocyst and in both ES and in trophectoderm stem (TS) cells. In TS cells, we were unable to demonstrate association of Rex-1 to the genes it associates with in ES cells, suggesting that association may be cell-type specific. Rex-1 might fine-tune pluripotency in ES cells by modulating Polycomb-mediated gene regulation.

Acute disabling low-back pain during intravenous administration of amiodarone: could intravenous to oral switch therapy be a safe strategy?

We report for the first time a case of an acute disabling low-back pain episode during intravenous administration of amiodarone in a patient with atrial fibrillation. The symptoms completely resolved after terminating the infusion, and switching amiodarone from intravenous to oral administration was well tolerated.