Validation of a hematology analyzer in donkey medicine

Asinina de Miranda is a protected donkey sub-species from the Mirandês plateau in northeastern of Portugal. Donkeys are animals that have substantially lost their place as working animals in modern society, this had led to a decrease in their population numbers. A need to preserve native species has led to the foundation of organizations like Associação para o Estudo e Proteção do Gado Asinino (AEPGA) and the development of studies regarding breed welfare, such as hematology. The IDEXX ProCyte Dx is a veterinary hematology analyzer validated for several species, but not for donkeys. The aim of this study was to validate the ProCyte Dx for Asinina de Miranda donkeys. The validation requires a controlled study of precision, carryover, linearity and comparison between the equipment and the manually obtained values for the leukocyte differential count and hematocrit. Results indicated coefficient of variation was good (below 5 %) for both the intra-assay and the inter-assay precision, except for basophils. Carryover was 0 % for all the parameters except platelets (5.88 %). Linearity showed a very high Pearson correlation coefficient, above 0.99, for erythrocytes, hematocrit, hemoglobin, leucocytes, neutrophils, lymphocytes, monocytes, eosinophils, platelets and plateletcrit. Comparison demonstrated excellent agreement for hematocrit (rs=0.96) and good Spearman rank correlation for neutrophils (rs=0.84) and lymphocytes (rs=0.90). Accuracy for total leukocyte count and platelets could not be determined. In conclusion, the ProCyte Dx seems appropriate to be used in Asinina de Miranda hematology.

Indexing calcium score of the aortic valve to the annulus area improves the grading of aortic stenosis severity in patients within the grey zone of aortic valve calcification

Introduction

Calcium score of the aortic valve (CaScAoV) is recommended as a supporting tool to assist in the grading of aortic stenosis (AS) severity when echocardiographic assessment is inconclusive. However, a significant proportion of patients have CaScAoV values within a “grey zone” between the “unlikely” and “likely” thresholds. The purpose of this study was to assess the potential usefulness of indexing CaScAoV to the area of the aortic annulus, in order to improve the discriminative power of CaScAoV in this subset of patients.

Methods

Consecutive patients evaluated at a single center TAVI program were retrospectively identified and included in the analysis if cardiac CT and echocardiography were performed within a 6-month timeframe. Those with LVEF <50%, indexed stroke volume <35 ml/m2, rheumatic heart disease, or bicuspid aortic valves were excluded. Severe AS was defined as mean transvalvular gradient ≥40 mmHg. The likelihood of severe AS assessed by CT was categorized according to the guideline-recommended sex-specific CaScAoV thresholds. Patients were considered to be in the “grey zone” if their CaScAoV values were between 800–1200 for women, and between 1600–2000 for men.

Results

A total of 655 patients were included (282 men (43.1%), median age 83 years [IQR 79–86]). AS was considered severe by echocardiographic criteria in 587 patients (89.6%), and moderate in the remainder. Median transvalvular gradient was 49 mmHg (IQR 43–59), and median CaScAoV values were 3329 (IQR 2356–4500) for men, and 1995 (IQR 1462–2781) for women.

Overall, 77 patients (11.7%) had CaScAoV values in the “grey zone”, of which 24 (31.2%) had moderate AS (Figure 1). Patients within this region of uncertainty were no different form the others in terms of age, sex, annulus size and body surface area.

In this subset of patients, indexing CaScAoV to aortic annulus area showed good discriminative power to identify severe AS (AUC 0.69, 95% CI 0.56–0.81, p=0.008). Using previously established thresholds (>300 AU/cm2 for women and >500 AU/cm2 for men), 48 patients (62.3%) were correctly reclassified (net reclassification index of 0.45, p=0.03). These findings were similar for both sexes.

Conclusion

In patients undergoing cardiac CT for known or suspected severe AS with CaScAoV values within the “grey zone”, indexing CaScAoV to the area of the aortic annulus improves the classification of AS severity and may decrease diagnostic uncertainty.

Funding Acknowledgement

Type of funding sources: None.

Myocardial deformation in athletes measured with feature tracking cardiovascular magnetic resonance

Background

Morphological changes of the heart associated with exercise are well studied. However, changes in myocardial mechanics of athlete's heart are less understood. The aim of this study was to analyze myocardial deformation parameters in athletes and controls, using feature tracking cardiac magnetic resonance (FT-CMR).

Methods

In a cohort of 73 athletes who had been submitted to CMR at 1.5T and 3 T (mean age 31±12 years, 69% males), we used CMR-FT to measure longitudinal, circumferential and radial strain and strain rates of both ventricles. Left ventricle (LV) longitudinal, circumferential and radial dyssynchrony index (L-SDI, C-SDI and R-CDI, respectively) was calculated as the standard deviation of the calculated time to peak strain percentages of the cardiac cycle with segmental strain analysis. We also measured these parameters in 73 age-matched healthy subjects.

Results

In comparison to the control subjects, athletes revealed lower left and right ventricle global longitudinal strain (−14.24% vs. −13.31%, p=0.03, and −18.12% vs. −15.95% p=0.01, respectively) and right ventricular (RV) global radial strain (19.28 vs 15.74, p<0.05) – Figure 1. There were no significant differences in LV global radial and circumferential strain. LV longitudinal, radial and circumferential systolic strain rate were also lower in athletes compared to controls (−0.69 s–1 vs. −0.78 s–1, p=0.04; 1.35 s–1 vs. 1.50 s–1, p=0.03: −0.92 s–1 vs −0.98 s–1, p=0.05, respectively). Regarding LV dyssynchrony index, we found no significant difference for L-SDI (10.76% vs. 10.72%, p=0.956), but athletes group showed lower C-SDI and R-SDI values (5.99% vs 4.84%, p=0.006, and 5.53% vs 4.47%, p=0.002).

Conclusion

Our study revealed attenuation of biventricular strain values and lower circumferential and radial LV dyssynchrony indexes in athletes, compared with healthy controls. We hypothesize that these differences may be related with exercise physiologic cardiac adaptations.

Funding Acknowledgement

Type of funding sources: None.

Predicting pacemaker dependency after TAVI with pre-procedural MSCT

Background and aim

High degree conduction disturbances is a burdensome complication of transcatheter aortic valve implantation (TAVI). There is limited data whether such disorders are permanent or reversible. Anatomic surrogates, such as membranous septum [MS, a distance marker from aortic annulus to His-bundle surge] and calcium distribution within aortic valve have been associated with pacemaker (PM) implantation. The aim of our study was to assess predictors of long-term pacemaker dependency following TAVI.

Methods

Single center prospectively included patients that underwent pacemaker implantation following TAVI (March 2017 to September 2020). Patients who were lost to follow up, with bicuspid aortic valve, previously implanted PM and non-available or low quality MSCT exam were excluded. On MSCT, MS length was measured on modified coronal view, the aortic-valvular complex (AVC) was characterized by leaflet sector and calcium distribution was assessed on a J-score threshold of 850-Hounsfield units. Pacemaker dependency was assessed by reducing ventricular pacing to 30 bpm and defined by subsequent complete AV dissociation in patients in sinus rhythm or an escape rhythm <50 bpm in atrial fibrillation, in addition of >90% pacing percentage since implantation.

Results

From the 352 patients with inclusion criteria, 67 underwent PM implantation (19%) and 55 included in the analysis (male 33.9%, median age=85) (Figure). Median time for pacemaker implantation was 3 days [interquartile range (IQR) 3–5 days], mostly due to complete auriculo-ventricular block (76.4%, N=42). PM dependency occurred in 14 out of 55 (25.5%) patients at mean follow up of 500±363 days. Patients with PM dependency tended to have deeper implantation depth, (6.2 mm vs 5.5 mm, p=0.096) and a significantly shorter MS (5.8 mm vs 6.8 mm, P-value = 0.031) (Table). Increasing MS length was independently associated with a lower risk of PM dependency [odds ratio (OR) 0.58 per mm; 95% CI: 0.35–0.98, p=0.04] regardless prosthesis choice. MS length under 5 mm had 97.6% specificity (95% CI: 87.1–99.9) and 85.7% positive predictive value for pacemaker dependency (AUC=76.7; 95% CI 63.3–87).

Conclusion

Our findings highlight the importance of MSCT-derived MS length to stratify the risk of long term need for pacemaker. Patients with short MS (<5mm) in addition to conduction abnormality following TAVI had a high likelihood of PM dependency on the long term and should be considered for prompt PM implantation.

Funding Acknowledgement

Type of funding sources: None.

Regurgitant volume to left ventricular end-diastolic volume ratio: the quest to identify Disproportionate MR is not over

Background

Quantification of secondary mitral valve regurgitation (SMR) remains challenging. Proportionate and Disproportionate SMR provides a conceptual framework that relates the degree of SMR to left ventricular dilatation and dysfunction. In line with this concept, regurgitant volume to LV end-diastolic volume ratio (Rvol/LVEDV) was recently proposed as a possible strategy to identify patients with Disproportionate SMR. The aim of this study was to validate this approach in a Portuguese cohort.

Methods

In a single center cohort of patients with heart failure and reduced left ventricular ejection fraction (HFrEF <50%) under optimal guideline-directed medical therapy (GDMT), we retrospectively identified those with at least moderate SMR. According to the published literature, we divided the study population into 2 risk groups: those with a Rvol/LVEDV ratio ≥20% (greater MR/smaller LVEDV) and those with a ratio <20% (smaller MR/ larger EDV). Cox regression and Kaplan-Meier survival analysis were used to assess the association between Rvol/LVEDV ratio and all-cause mortality.

Results

A total of 154 patients (mean age 69±12 years; 81% male) were included. Mean LVEF was 31±8% and median LVEDV was 193 mL (IQR: 155 to 236 mL). There were 74 patients (48.1%) with a Rvol/LVEDV ratio <20% and 80 patients (51.9%) Rvol/LVEDV ratio ≥20%. Regarding GDMT, 141 (91.6%) received beta-blockers, 139 (90.3%) angiotensin converting–enzyme inhibitors/angiotensin receptor blockers and 77 (50.0%) were under mineralocorticoid therapy. Also, there were patients 49 (31.8%) under cardiac resynchronization therapy and 40 patients (26.0%) had an implantable cardioverter defibrillator. During a median follow-up of 2.1 years (IQR 0.7 to 3.8 years), 92 (59.7%) patients died. Cox regression and survival analysis showed no mortality difference between patients with a Rvol/LVEDV ratio <20% and those with a ratio ≥20% (HR: 1.04; 95% CI 0.69–1.57; P=0.854; Log-rank P=0.967) – see also figure.

Conclusion

In a Portuguese cohort of HFrEF patients under optimized GDMT and with at least moderate SMR, the Rvol/LVEDV ratio was not associated with an increased risk of all-cause mortality. As such, the Rvol/LVEDV ratio does not seem to be a reliable surrogate of Disproportionate SMR, possibly because it does not account for the degree of LV dysfunction.

Funding Acknowledgement

Type of funding sources: None.

Coronary artery calcium score to predict coronary CT angiography interpretability. An old problem revisited

Introduction

Clinical guidelines recommend against the use of coronary computed tomography angiography (CCTA) in patients with heavy calcification due to interpretability concerns, but no specific approach or threshold is provided. Recently, alternative methods have been proposed as more reliable predictors of CCTA interpretability than the classic coronary artery calcium score (CACS). The purpose this study was to compare the performance of different measures of coronary calcification as predictors of CCTA interpretability.

Methods

We conducted a retrospective analysis of consecutive patients undergoing CACS and CCTA between 2018 and 2020. The key exclusion criteria were known coronary artery disease, CACS of zero, and presence of non-assessable coronary lesions for reasons other than calcification (movement/gating artifacts or vessel diameter <2mm). CCTA studies were considered non-interpretable if the main reader considered one or more coronary lesions non-assessable due to calcification. Three different measures of coronary calcification were compared using ROC curve analysis: 1) total CACS; 2) CACS-to-lesion ratio (total CACS divided by the number of calcified plaques); and 3) calcium score of the most calcified plaque. Decision-tree analysis was performed to identify the algorithm that best predicts CCTA interpretability.

Results

A total of 432 patients (191 women, mean age 64±11 years) were included. Overall, 31 patients (7.2%) had a non-interpretable CCTA due to calcification. Patients with non-interpretable CCTA had higher CACS (median 589 vs. 50 AU, p<0.001), higher CACS-to-lesion ratio (median 43 vs. 14 AU/lesion, p<0.001), and higher score of the most calcified plaque (median 445 vs. 43 AU, p<0.001). Among the 3 methods, CACS showed the highest discriminative power to predict a non-interpretable CCTA (C-statistic 0.93, 95% CI 0.89–0.95, p<0.001) – Figure 1.

Decision-tree analysis identified a single-variable algorithm (CACS value ≤515 AU) as the best discriminator of CCTA interpretability: 396 of the 409 patients (97%) with CACS ≤515 AU had an interpretable CCTA, whereas only 5 of the 23 patients (22%) with CACS >515 AU had an interpretable test, yielding a total of 96% correct predictions.

Conclusions

The recently proposed and more complex measures of coronary calcification seem unable to outperform total CACS as a predictor of CCTA interpretability. A simple CACS cutoff-value around 500 AU remains the best discriminator for this purpose.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Patients undergoing invasive coronary angiography after a positive single-photon emission computed tomography or a positive stress cardiac magnetic resonance - What to expect at the cath lab

Funding Acknowledgements

Type of funding sources: None.

Background

 Randomized controlled trials comparing stress cardiac magnetic resonance (CMR) and single-photon emission computed tomography (SPECT) suggest similar diagnostic accuracy for detecting obstructive coronary artery disease (CAD). However, there are few data on whether or not this remains true in routine clinical practice.

The aim of this study was to assess the clinical and angiographic characteristics of patients undergoing invasive coronary angiography (ICA) after a positive stress CMR or positive SPECT, and to compare their positive predictive value with published results from the CE-MARC trial.

Methods

In this retrospective tertiary-center analysis, we included 429 patients (mean age 67 ± 10 years, 28% women, 42% diabetic) undergoing ICA between January 2016 and December 2020, after a positive stress CMR or positive SPECT. Regarding stress test, an adenosine protocol was performed in all stress CMR and in 76.4% (n = 272) of stress SPECT. 

Stress test results, including ischemia location and severity, were classified as reported by their primary readers. Patients with missing data on key variables, and those in whom microvascular disease was considered likely in the original stress test report were excluded. Obstructive CAD was defined as any coronary artery stenosis ≥ 50% in a vessel compatible with the ischemic territory on stress testing.

Results

Out of the total 429 patients, 356 (83%) were referred after a positive SPECT, and 73 (17%) after a positive stress CMR. Patients did not differ regarding age, cardiovascular risk factors, previous revascularization or left ventricular dysfunction, but patients with SPECT were more frequently male (p = 0.046). Overall, 320 patients (75%) had obstructive CAD on ICA. The prevalence of obstructive CAD was similar in patients with positive SPECT vs. positive stress CMR (76.1% vs. 80.8%, respectively, p = 0.385). There were also no significant differences in the prevalence of left main or 3-vessel disease (9.0% vs. 9.6%, p = 0.871, and 19.7% vs. 23.3% p = 0.483, respectively). Revascularization was performed or planned in 59.3% of patients in the SPECT group, and 52.1% of those in the stress CMR group (p = 0.255). The positive predictive values of both techniques were similar to those reported in the CE-MARC trial (Figure), and would increase to 88.1% and 89.4% for SPECT and stress CMR, respectively, if patients reported as having only mild ischemia were excluded.

Conclusion

In this tertiary center analysis, stress CMR and SPECT showed similar positive predictive values, comparable to those reported in the CE-MARC trial.

Calcium score of the aortic valve as a predictor of aortic stenosis severity

Funding Acknowledgements

Type of funding sources: None.

Background

The calcium score of the aortic valve (CaScAoV) is now recommended as a supporting tool to assist in the grading of aortic stenosis (AS) severity when echocardiographic assessment is inconclusive. However, the proposed CaScAoV cut-offs for considering severe AS "unlikely", "likely", or "very likely" have never been validated in Portuguese cohorts.

Aim

The purpose of this study was to assess the performance of the proposed CaScAoV cut-offs in identifying patients with severe aortic stenosis.

Methods

A total of 513 consecutive patients (median age 83 years [IQR 79–87], 38% males) evaluated at a single-centre TAVI-programme between Jan/2016 and Nov/2019 were retrospectively identified. Only patients with an ECG-gated cardiac computed tomography (CT) and a transthoracic echocardiography performed within a 6-month time-frame were included. Main exclusion criteria were left ventricular ejection fraction < 50%, indexed stroke volume < 35 ml/m2, previous valve surgery and

bicuspid aortic disease. CaScAoV was measured according to the Agatston method (Agatston units – AU). As previously reported, the likelihood of aortic stenosis as assessed by CT was categorized as: "very likely" (>3000 AU for men, >1600 AU for women); "likely" (>2000 AU for men, >1200 AU for women) ; or unlikely (<1600 AU for men, <800 AU for women). Diagnostic tests performance measures were calculated for each category. Separate analyses were performed for each gender.

Results

Severe AS (mean gradient ≥ 40 mmHg) was present in 422 patients (overall 82.3%: 83.1% in females and 80.8% in males), with a median transvalvular gradient of 49 mmHg (IQR 42 – 60).

Overall, the discriminative ability of the CaScAoV to distinguish severe from non-severe AS was higher in men when compared with women (c-statistic 0.86 [95%CI 0.80 – 0.93] vs. 0.72 [95%CI 0.64 – 0.80], p for comparison < 0.001). In males, the "very likely" cut-off had a sensitivity of 71% (95%CI 63 – 78%), a specificity of 81% (95%CI 65 – 92%), a positive predictive value (PPV) of 94% (95%CI 89 – 97%) and a negative predictive value (NPV) of 40% (95%CI 33 – 46%) for the diagnosis of severe AS. Conversely, in women the sensitivity was 75% (95%CI 69 – 80%), specificity was 57% (95%CI 43 – 71%), PPV was 90% (95%CI 86 – 92%) and NPV was 32% (95%CI 25 – 39%).

On the other end of the spectrum, the "unlikely" cut-off showed poor performance in dismissing severe AS, particularly in females – NPV of 43% (95%CI 25-63%) in women vs. 83% (95%CI 63-93%) in men.

Conclusion

In our population, the discriminative power of CaScAoV for identifying patients with severe AS was lower than in previously published cohorts, particularly in females. While very high CaScAoV is strongly supportive of severe AS, caution should be employed when interpreting low CaScAoV values in women, since the recommended cut-off value does not allow the safe exclusion of severe aortic stenosis.

Abstract Figure. Waterfall chart of individuals CaScAoV

A FABP4-PPARγ signaling axis regulates human monocyte responses to electrophilic fatty acid nitroalkenes

Nitro-fatty acids (NO2-FA) are electrophilic lipid mediators derived from unsaturated fatty acid nitration. These species are produced endogenously by metabolic and inflammatory reactions and mediate anti-oxidative and anti-inflammatory responses. NO2-FA have been postulated as partial agonists of the Peroxisome Proliferator-Activated Receptor gamma (PPARγ), which is predominantly expressed in adipocytes and myeloid cells. Herein, we explored molecular and cellular events associated with PPARγ activation by NO2-FA in monocytes and macrophages. NO2-FA induced the expression of two PPARγ reporter genes, Fatty Acid Binding Protein 4 (FABP4) and the scavenger receptor CD36, at early stages of monocyte differentiation into macrophages. These responses were inhibited by the specific PPARγ inhibitor GW9662. Attenuated NO2-FA effects on PPARγ signaling were observed once cells were differentiated into macrophages, with a significant but lower FABP4 upregulation, and no induction of CD36. Using in vitro and in silico approaches, we demonstrated that NO2-FA bind to FABP4. Furthermore, the inhibition of monocyte FA binding by FABP4 diminished NO2-FA-induced upregulation of reporter genes that are transcriptionally regulated by PPARγ, Keap1/Nrf2 and HSF1, indicating that FABP4 inhibition mitigates NO2-FA signaling actions. Overall, our results affirm that NO2-FA activate PPARγ in monocytes and upregulate FABP4 expression, thus promoting a positive amplification loop for the downstream signaling actions of this mediator.

P2849Prevalence and significance of sustained pulmonary vein isolation in repeat AF ablation procedures

Introduction

Pulmonary vein (PV) reconnection is a common cause of relapse after catheter ablation of atrial fibrillation (AF). However, some patients have AF recurrence despite durable PV isolation. The aim of this study was to assess the PV isolation status at the time of a second catheter ablation (redo) procedure, and its relationship with subsequent AF relapse.

Methods

Consecutive patients with symptomatic drug-resistant AF who underwent redo procedures from January 2006 to December 2017 were identified in a single-center observational registry. Pulmonary vein isolation status was assessed during the electrophysiologic study with a circular mapping catheter. Additional radiofrequency (RF) energy applications were also recorded. AF relapse was defined as symptomatic or documented AF/atrial tachycardia/atrial flutter after a 3-month blanking period.

Results

We identified 240 patients (77 [32%] females, median age 61 [IQR 53–67] years, 85 [35%] with non-paroxysmal AF) undergoing redo procedures during the study period. At the time of redo, 17 (7%) of the patients presented bidirectional conduction block of all PVs. PV reconnection occurred in 157 (65%) of cases in the left superior vein, 142 (59%) in the left inferior vein, 177 (73%) in the right superior vein, and 163 (68%) in the right inferior vein (table). All of the PVs were reconducted in 91 (38%) patients. Additional RF applications were performed in the left atrium (LA) roof, LA posterior wall, cavotricuspid isthmus, mitral isthmus, superior vena cava, coronary sinus, and left atrial appendage ostium, at the operator's discretion (table 1).

Over a median follow-up of 2-years (IQR 1–5), 126 patients (53%) suffered AF recurrence, yielding a mean relapse rate of 17%/year. In multivariate Cox regression analysis, the lack of PV reconnection at the time of redo emerged as an independent predictor of subsequent relapse (HR 1.97, 95% CI 1.12–3.49, p=0.019) even after adjustment for univariate predictors including non-paroxysmal AF, body mass index, female sex, and active smoking.

Conclusion

In patients undergoing redo AF ablation procedures, less than 10% present with complete PV isolation. Despite being relatively infrequent, this finding is independently associated with greater likelihood of subsequent recurrence, suggesting that other mechanisms, not fully addressed by additional RF applications, are at play.

P5699Endocardial vs. epicardial ventricular tachycardia ablation: a propensity score matched analysis

Introduction

Direct comparisons of long-term clinical outcomes of endocardial vs. epicardial catheter ablation techniques for drug-resistant ventricular tachycardia (VT) have been scarcely reported.

We aim to compare the long-term efficacy and safety of endocardial vs. epicardial catheter ablation (END-ABL and EPI-ABL, respectively) in a propensity score (PS) matched population.

Methods

Single-center observational registry including 215 consecutive patients who underwent END-ABL (181) or EPI-ABL (n=34) for drug-resistant VT between January 2007 and June 2018. Efficacy endpoint was defined as VT-free survival after catheter ablation, while safety outcomes were defined by 30-days mortality and procedure-related complications. A propensity score was used to match patients in a 1:1 fashion according to the following variables: VT storm at presentation, left ventricular ejection fraction (LVEF), New York Heart Association (NYHA) class III/IV at presentation, ischemic ethology, presence of implantable cardioverter-defibrillator (ICD), and previous endocardial catheter ablation. Independent predictors of VT recurrence were assessed by Cox regression.

Results

The PS yielded two groups of 31 patients each well matched for baseline characteristics (Table 1). Over a median follow-up of 2 years (IQR 1–3), 58% (n=18) ENDO-ABL patients had VT recurrence vs. 26% (n=8) in the EPI-ABL group (P=0.020). The yearly rates of VT recurrence were 28%/year for END-ABL vs. 11%/year for EPI-ABL (P=0.021). Multivariate survival analysis identified previous endocardial ablation (HR= 3.52; 95% CI 1.17–10.54, p=0.026) and VT storm at presentation (HR=3.57; 95% CI 1.50–8.50, p=0.004) as independent predictors of VT recurrence. EPI-ABL was independently associated with fewer VT recurrences (HR=0.28; 95 CI 0.12–0.69, p=0.005), but only in patients with a previous endocardial ablation (p for interaction = 0.004) – Figure A.

No patients died at 30-days post-procedure. Hospital length of stay was similar between END-ABL and EPI-ABL (5 vs. 4 days respectively, p=0.139), as was the complication rate (6.5% vs. 12.9% respectively, p=0.390), although driven by different causes (Table 1).

Conclusion

VT storm at presentation and previous catheter ablation were independent predictors of VT recurrence. In patients with a previous failed endocardial catheter ablation, epicardial ablation seems to provide greater VT-free survival than repeat endocardial ablation. Both strategies seem equally safe.

1204Pericardial fat volume outperforms classic risk markers in the prediction of relapse after pulmonary vein isolation

Introduction

Pericardial adipose tissue has been implicated in the pathophysiology of atrial fibrillation (AF), but its relevance to clinical practice remains uncertain. The aim of this study was to assess the relative importance of pericardial fat as predictor of recurrence after pulmonary vein isolation (PVI).

Methods

We assessed 453 patients (278 men, age 61±13 years, 348 paroxysmal AF) with symptomatic AF undergoing cardiac CT prior to a PVI procedure. Pericardial fat was quantified on contrast-enhanced images using a new simplified semi-automated method. The study endpoint was symptomatic and/or documented AF recurrence.

Results

Over a median follow-up of 14 months (IQR 7–23), 170 patients (38%) relapsed. Survival analysis showed significant differences in AF-free survival across tertiles of pericardial fat (Figure). Pericardial fat volume was weakly correlated to body mass index [(BMI), Pearson's R=0.34]. After adjustment for BMI and other univariate predictors of relapse, three variables emerged independently associated with time to AF recurrence: non-paroxysmal AF (HR 2.08, 95% CI: 1.51–2.87, p<0.001), indexed left atrial (LA) volume (HR 1.02 per mL/m2, 95% CI: 1.01–1.02, p<0.001), and indexed pericardial fat volume (HR 1.50 per mL/m2, 95% CI: 1.37–1.64, p<0.001). Based on the Wald test, indexed pericardial fat volume was the strongest of these predictors of relapse (X2 values of 20, 13, and 77, respectively). The population attributable risk (PAF) was higher for pericardial fat (PAF=37% for 1st vs 4th quartile) vs LA volume (PAF=11% for 1st quartile vs 4th quartile) and non-paroxysmal AF (PAF=23%). Pericardial fat volume also showed greater discriminate power than indexed LA volume, with a C-statistic of 0.80 (95% CI 0.76–0.85) vs. 0.61 (95% CI 0.55–0.66), p for difference <0.001. The method for quantifying pericardial fat showed high inter-observer reproducibility (Pearson's R=0.90) and was quick to perform (38±3 seconds).

Conclusion

Pericardial fat volume is a strong independent predictor of AF relapse after PVI, outperforming classic risk markers such as LA volume and type of AF. The underlying mechanisms of this association deserve further study. Meanwhile, this simple parameter may help select patients who are more likely to derive sustained benefit from AF ablation.

Lactose-crosslinked fish gelatin-based porous scaffolds embedded with tetrahydrocurcumin for cartilage regeneration

Tetrahydrocurcumin (THC) is one of the major colourless metabolites of curcumin and shows even greater pharmacological and physiological benefits. The aim of this work was the manufacturing of porous scaffolds as a carrier of THC under physiological conditions. Fish-derived gelatin scaffolds were prepared by freeze-drying by two solutions concentrations (2.5% and 4% w/v), cross-linked via addition of lactose and heat-treated at 105 °C. This cross-linking reaction resulted in more water resistant scaffolds with a water uptake capacity higher than 800%. Along with the cross-linking reaction, the gelatin concentration affected the scaffold morphology, as observed by scanning electron microscopy images, by obtaining a reduced porosity but larger pores sizes when the initial gelatin concentration was increased. These morphological changes led to a scaffold's strength enhancement from 0.92 ± 0.22 MPa to 2.04 ± 0.18 MPa when gelatin concentration was increased. THC release slowed down when gelatin concentration increased from 2.5 to 4% w/v, showing a controlled profile within 96 h. Preliminary in vitro test with chondrocytes on scaffolds with 4% w/v gelatin offered higher metabolic activities and cell survival up to 14 days of incubation. Finally the addition of THC did not influence significantly the cytocompatibility and potential antibacterial properties were demonstrated successfully against Staphylococcus aureus.

Synthesis of bioinspired collagen/alginate/fibrin based hydrogels for soft tissue engineering

Hydrogels based on natural polymers offer a range of properties to mimic the native extracellular matrix, and provide microenvironments to preserve cellular function and encourage tissue formation. A tri-component hydrogel using collagen, alginate and fibrin (CAF) was developed and investigated at three collagen concentrations for application as a functional extracellular matrix analogue. Physical-chemical characterization of CAF hydrogels demonstrated a thermo-responsive crosslinking capacity at physiological conditions with stiffness similar to native soft tissues. CAF hydrogels were also assessed for cytocompatibility using L929 murine fibroblasts, pancreatic MIN6 β-cells and human mesenchymal stem cells (hMSCs); and demonstrated good cell viability, proliferation and metabolic activity after 7 days of in vitro culture. CAF hydrogels, especially with 2.5% w/v collagen, increased alkaline phosphatase production in hMSCs indicating potential for the promotion of osteogenic activity. Moreover, CAF hydrogels also increased metabolic activity of MIN6 β-cells and promoted the reconstitution of spherical pseudoislets with sizes ranging between 50 and 150 μm at day 7, demonstrating potential in diabetic therapeutic applications.

Alginate-based hydrogels functionalised at the nanoscale using layer-by-layer assembly for potential cartilage repair

Injuries to articular cartilage are frequently difficult to repair, in part because of the poor regenerative capacity of this tissue. To date, no successful system for complete regeneration of the most challenging cartilage defects has been demonstrated. The aim of this work was to develop functionalised hydrogels at the nanoscale by Layer-by-Layer (LbL) assembly to promote cartilage healing. Hydrogels, based on sodium alginate (NaAlg) and gelatin (G), were prepared by an external gelation method consisting of CaCl₂ diffusion and genipin addition for G crosslinking. Successively, hydrogels were coated with G to obtain a positive charge on the surface, then functionalised by LbL assembly to create 16 nanolayers, based on poly(styrene sulfonate)/poly(allyl amine) (PSS/PAH), including a specific peptide sequence (CTATVHL) and transforming growth factors β1 (TGF-β1). Physico-chemical properties were evaluated by XPS, ATR-FTIR and rheological analyses while in vitro cytocompatibility was studied using bovine articular chondrocytes (BAC). XPS spectra showed N_1s and S_2p peaks, indicating that PAH and PSS have been introduced with success. ATR-FTIR indicated the specific PAH and PSS absorption peaks. Finally, the biomolecule incorporation influenced positively the processes of BAC adhesion and proliferation, and glycosamynoglycan secretion. The functionalised alginate-based hydrogels described here are ideally suited to chondral regeneration in terms of their integrity, stability, and cytocompatibility.

Epidemiology, risk factors and outcomes of multi-drug-resistant bloodstream infections in haematopoietic stem cell transplant recipients: importance of previous gut colonization

BACKGROUND

Bloodstream infections (BSI) are a major complication in the early phase of a haematopoietic stem cell transplant (HSCT).

AIM

To describe the incidence and risk factors for BSI occurring in the pre-engraftment phase of HSCT, and its impact on mortality.

METHODS

Clinical variables of 232 HSCT patients were analysed retrospectively between 2014 and 2015. Univariate Cox regression analyses were performed to test the association between each covariate and the outcome. Covariates with P < 0.10 on univariate analysis were included in a multiple Cox regression analysis using a backward elimination method.

FINDINGS

The cumulative incidence of BSI was 25.4%, mainly caused by Gram-negative bacteria (GNB) (55.2%). Approximately 40.5% of the patients had gut colonization by multi-drug-resistant (MDR) bacteria (vancomycin-resistant enterococcus and carbapenem-resistant GNB). Among patients colonized by MDR GNB, 20% developed an overt BSI due to MDR bacteria with the same pattern of sensitivity. Of the 13 deaths related to infection, 10 were patients with BSI caused by MDR GNB. The independent risk factors for BSI were gut colonization by MDR bacteria including GNB (P < 0.001) and duration of neutropenia >10 days (P = 0.005), and those associated with BSI caused by MDR bacteria were age >62 years (P = 0.03), use of total parenteral nutrition (TPN) (P < 0.001) and previous gut colonization by MDR GNB (P = 0.002).

CONCLUSIONS

Previous gut colonization by MDR was an independent risk factor for BSI, together with TPN and age, and had an impact on outcome. These findings suggest that gut decolonization may be a potential strategy to prevent BSI.

Parasite molecules and host responses in cystic echinococcosis

Cystic echinococcosis is the infection by the larvae of cestode parasites belonging to the Echinococcus granulosus sensu lato species complex. Local host responses are strikingly subdued in relation to the size and persistence of these larvae, which develop within mammalian organs as 'hydatid cysts' measuring up to tens of cm in diameter. In a context in which helminth-derived immune-suppressive, as well as Th2-inducing, molecules garner much interest, knowledge on the interactions between E. granulosus molecules and the immune system lags behind. Here, we discuss what is known and what are the open questions on E. granulosus molecules and structures interacting with the innate and adaptive immune systems, potentially or in demonstrated form. We attempt a global biological approach on molecules that have been given consideration primarily as protective (Eg95) or diagnostic antigens (antigen B, antigen 5). We integrate glycobiological information, which traverses the discussions on antigen 5, the mucin-based protective laminated layer and immunologically active preparations from protoscoleces. We also highlight some less well-known molecules that appear as promising candidates to possess immune-regulatory activities. Finally, we point out gaps in the molecular-level knowledge of this infectious agent that hinder our understanding of its immunology.

Floristic and phytosociology in dense "terra firme" rainforest in the Belo Monte Hydroelectric Plant influence area, Pará, Brazil

The objective of the present study was to characterise the floristic and phytosociological composition on a stretch of dense "Terra Firme" rainforest located in the Belo Monte hydroelectric plant area of influence, located in the state of Pará, Brazil. All trees with DAP >10 cm situated in 75 permanent plots of 1 ha were inventoried. 27,126 individuals trees (361 ind.ha-1), distributed in 59 botanical families, comprising 481 species were observed. The families with the largest number of species were Fabaceae (94), Araceae (65) and Arecaceae (43), comprising 43.7% of total species. The species Alexa grandiflora (4.41), Cenostigma tocantinum (2.50) and Bertholletia excelsa (2.28) showed the highest importance values (IV). The ten species with greater IV are concentrated (22%). The forest community has high species richness and can be classified as diverse age trees, heterogeneous and of medium conservation condition.

Responses of CYP450 dependent system to aliphatic and aromatic hydrocarbons body burden in transplanted mussels from South coast of Portugal

Mussels Mytilus galloprovincialis were cross-transplanted at South Portugal from a reference site (site 1) to a site more contaminated with hydrocarbon compounds (site 2), and vice versa, in an active biomonitoring (ABM) concept, to assess the biotransformation capacity catalyzed by the mixed function oxygenase (MFO) system. Total alkanes (TAlk), the unresolved complex mixture (UCM), and total polycyclic aromatic hydrocarbons (TPAHs) concentration increased respectively 6, 4.4 and 4.2 fold relatively to control, in mussels transplanted from site 1 to 2. In the cross-transplant, a 48, 57 and 62% depuration of TAlk, UCM and TPAHs concentrations occurred by the end of the 3-4th week. Petrogenic and biogenic (marine and terrigenous) sources of AHs, and petrogenic and pyrolitic (biomass and oil/fuel incomplete combustion) sources of PAHs were detected at both sites. CYP450, CYT b (5) and NADPH-RED in mussels transplanted from site 1 to 2 were induced from day 0 to 28, with a total increase of 35, 32 and 35%, respectively, while biochemical equilibrium to lesser environmental contamination occurs in mussels transplanted from site 2 to 1. A significant relationship between CYP450 and NADPH-RED was found with TPAH, with distinctive behavior at the two sites. MFO system components increase with exposure time at one site and decreases in the other, reflecting an adaptation to distinct environmental hydrocarbon loads. The ABM strategy proved to be useful to understand the environment real impact on the biochemical responses in mussels' local populations. In this study, CYP450 and NADPH-RED are a useful biomarker for hydrocarbon exposure.

Prevalence of diabetes mellitus in a rural population of Goa, India

BACKGROUND

We aimed to estimate the prevalence of diabetes mellitus and study the associated factors in a rural population in Goa, India.

METHODS

A cross-sectional study was done in the rural area of Mandur, Goa. Participants>20 years of age were selected by systematic random sampling. They were interviewed with the help of a structured, pretested questionnaire. This was followed by clinical examination, anthropometry and relevant laboratory investigations. Diabetes mellitus was defined as per the American Diabetes Association (ADA) criteria. Statistical analysis was done using the SPSS software package (version 14.0).

RESULTS

The prevalence of diabetes mellitus in the study population was 10.3% (130/1266) with a prevalence of 8.4% among men and 12% among women. On bivariate analysis, the prevalence of diabetes mellitus was found to be significantly associated with age, occupation, family income, family history of diabetes, smoking, obesity, hypertension, and high serum cholesterol and triglycerides levels. Multiple logistic regression analysis identified age, family history, hypertension, smoking, total cholesterol and triglyceride as the Independently associated variables for diabetes mellitus.

CONCLUSION

Innovative community outreach programmes are required to create awareness, and for screening and treatment of diabetes mellitus to curb the growing epidemic of diabetes in the population.

Organic pollutants in microplastics from two beaches of the Portuguese coast

Microplastics pose a threat to coastal environments due to their capacity to adsorb persistent organic pollutants (POPs). These particles (less than 5 mm in size) are potentially dangerous to marine species due to magnification risk over the food chain. Samples were collected from two Portuguese beaches and sorted in four classes to relate the adsorption capacity of pollutants with color and age. Polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and DDTs were analysed on pellets through gas chromatography mass spectrometry (GC-MS), and types of plastic were identified using Fourier transformed infra-red spectroscopy (micro-FTIR). Microplastics were mostly polyethylene and polypropylene. Regarding sizes, some fibres ranged from 1 to 5 μm in diameter and were 500 μm in length. The majority of samples collected had sizes above 200 μm. Black pellets, unlike aged pellets, had the highest concentrations of POPs except for PAHs in Fonte da Telha beach. PAHs with higher concentrations were pyrene, phenantrene, chrysene and fluoranthene. Higher concentrations of PCBs were found for congeners 18, 31, 138 and 187. Further investigation is necessary to understand the relationship between plastic degradation and adsorption for different pollutants.

Validating a multi-biomarker approach with the shanny Lipophrys pholis to monitor oil spills in European marine ecosystems

Oil spills are an importance source of polycyclic aromatic hydrocarbons (PAHs) in the aquatic environment. Intertidal communities are particularly sensitive since most organisms from these ecosystems are sessile or present reduced mobility. Hence, it is important to validate the use of resident species as sentinels to characterize the impact of oil spills on the rocky shores and the improvement during the restoration process. Recently the advantages of using the shanny Lipophrys pholis in pollution monitoring within the northwestern Atlantic coast has been pointed out. Therefore, with the aim of further validating the use of L. pholis in pollution monitoring associated with petrogenic hydrocarbon contamination, a multi-biomarker approach study was carried out 1 week after a moderate oil spill from the waste treatment plant (WTP) of the major Portuguese refinery in the north of Portugal (Petrogal). Fish collected at 2 km from the accident displayed a significant induction of ethoxyresorufin-O-deethylase activity (EROD) and fluorescent aromatic compounds (FACs) in bile (up to a 5-fold induction) in comparison with the pre-spill scenario, and a 15% induction in erythrocytic nuclear abnormalities (ENA), a biomarker of genotoxicity. In contrast, no significant differences were recorded in the reference site. In order to better characterize the time-course accumulation of FACs in bile after a PAH insult, laboratory exposure of L. pholis to benzo[a]pyrene (B[a]P) was performed. A clear dose-response accumulation of B[a]P metabolites was observed that closely reflected nominal exposure concentrations already after 3d. Overall, the findings of the present study highlight the potential of L. pholis in pollution monitoring dealing not only with chronic contamination, but also with oil spill accidents of a moderate scale. Taking into consideration that EROD and FACs determinations in L. pholis are cost effective, rapid and easy to use, they offer a great potential to be incorporated into risk assessment of PAHs in the scope of national monitoring programs and the European Water Policy legislation.

Prevalence of human cysticercosis and taeniasis in rural Goa, India

A cross sectional study among 450 individuals selected by strafified random sampling was carried out in rural Goa to find out the prevalence of cysticercosis and taeniasis, as well as to study the role of various factors associated with this diseases. The study participants were administered a pre-tested structured questionnaire and subsequently blood and stool samples were examined. SPSS software was used to analyze the data statistically. The sero-prevalence of cysterosis was 22.4%, which increased with age. Prevalence of taeniasis was 9.7% by stool examination. Individuals with taeniasis were thrice more likely to have cysticercosis; however no association between sero-positivity for cysterosis and pork consumption as well as religion could be established. The study confirmed a high sero-prevalence of cysticercosis in Goa underscoring the need to general awareness about good cooking habits and sanitation.

Resistance of the Echinococcus granulosus cyst wall to complement activation: analysis of the role of InsP6 deposits

The larva of the cestode Echinococcus granulosus (hydatid cyst) is protected by the acellular laminated layer (LL). The mechanisms that make this thick coat a poor activator of host complement are incompletely understood. The structure binds, through unknown motifs, the host regulator of the alternative complement pathway (ACP), factor H. A second potential mechanism of ACP regulation, the inhibition of factor B activation, was detected in assays employing purified components (Immunopharmacology 42 : 91). The inhibitor was subsequently identified as myo-inositol hexakisphosphate (InsP(6)), which in the form of nano-deposits is a major component of the LL (Biochem J 362 : 297; J Cell Biochem 93 : 1272; FEBS J 273 : 3192). In this report we show that colloidal InsP(6 )solids inhibit factor B activation, through adsorption and associated impairment of C3b binding. However, this interaction is not relevant in the presence of serum proteins. In serum, InsP(6) deposits instead bind C1q, and initiate complement activation. This activation is curtailed through efficient C3b inactivation, previously shown to be entirely factor H-dependent, and now observed to be independent of the InsP(6) deposits. Therefore the complement resistance of the LL must be based on functional factor H binding sites present on the mucin-based meshwork that is its other major constituent.

Sediment contamination, bioavailability and toxicity of sediments affected by an acute oil spill: Four years after the sinking of the tanker Prestige (2002)

Sediment contamination and three bioassays were used to determine the sediment quality four years after an oil spill (Prestige, 2002): the Microtox test, a 10-day bioassay using the amphipod Ampelisca brevicornis, and a polychaete 10-day toxicity test with the lugworm Arenicola marina. In addition, bioaccumulation of PAHs was examined in the polychaete after 10 days of exposure. The results obtained from the toxicity tests and bioaccumulation analyses were statistically compared to the sediment chemical data, in order to assess the bioavailability of the contaminants, their effects, and their relationship with the oil spill. The sediments studied were from two areas of the Galician Coast (NW Spain): the Bay of Corme-Laxe and the Cíes Island, located in the Atlantic Island National Park. The results point to a decrease in contamination with respect to previous studies and to the disappearance of the acute toxicity four years after the oil spill. However an important bioaccumulation of PAHs was detected in the organisms exposed to sediments from Corme-Laxe, suggesting that despite the recovery of the environmental quality of the area, effects in the biota might be occurring.

Comparative petroleum hydrocarbons levels and biochemical responses in mussels from hydrothermal vents (Bathymodiolus azoricus) and coastal environments (Mytilus galloprovincialis)

Aliphatic hydrocarbons and PAHs in the whole soft tissues of Bathymodiolus azoricus from three Mid-Atlantic Ridge hydrothermal vents (Menez-Gwen, Lucky Strike and Rainbow), and Mytilus galloprovincialis from three contaminated coastal sites in South Portugal were analysed, and its effects on the digestive gland microsomes mixed-function oxygenase system (MFO) were assessed. Aliphatic hydrocarbons levels were present in the same magnitude in both coastal and hydrothermal environments, while the UCM (unresolved complex mixture) for coastal mussels were higher than in vent mussels. In general, significantly higher PAHs concentrations were found in coastal mussels, compared to B. azoricus where low molecular weight PAHs (2-3 rings) represented the majority of PAHs contrarily to what was observed in M. galloprovincialis. The MFO components were present in both mussel species, and were detected in vent mussels for the first time. However this system seems to have different roles in species from these contrasting environments. In coastal mussels MFO responded to hydrocarbon contamination while response in hydrothermal organisms appeared to be related mainly to endogenous factors.

Is Arenicola marina a suitable test organism to evaluate the bioaccumulation potential of Hg, PAHs and PCBs from dredged sediments?

This paper presents the results of investigations on the suitability of lugworms (Arenicola marina) to study the bioaccumulation potential of Hg, PCB and PAH compounds from dredged sediments upon laboratory exposure. The results of tissue concentrations for several sediments from Spanish ports showed that it is possible to identify increased levels of contaminants in lugworms just after 10 days of exposure although different bioaccumulation trends were shown amongst compounds and sediments. Total and organic Hg compounds were accumulated following a non-linear trend, with a sharp increase of tissue concentrations in lugworms exposed to levels of contamination associated to a significant increase in mortality. Interestingly organic Hg compounds accounted for an average of 40% of the total Hg in lugworms exposed to sediments presenting sublethal concentrations while, when exposed to sediments presenting lethal concentrations, organic Hg compounds only accounted for 4% of the total Hg accumulated in lugworms. While lugworms seem to readily accumulate Hg and PCB compounds, with some variability explained by the organic matter content in sediments or other factor for which it accounts for, the results for PAHs suggest a more complex process of bioaccumulation as no relationship was observed between the measured concentrations in sediments and in lugworms, not even after correcting the results for this factor. Besides, the differences in the calculated BSAFs for each compound and for each sediment supported the use of bioassays for evaluating the bioaccumulation potential of sediment-bound contaminants as part of the assessment framework required in pre-dredging investigations, as they still offer unique information about the bioavailability of sediment-bound contaminants.

The use of the shanny Lipophrys pholis for pollution monitoring: a new sentinel species for the northwestern European marine ecosystems

The contamination of aquatic ecosystems by organic contaminants such as polycyclic aromatic hydrocarbons (PAHs) is a matter of great concern. Mussels have been extensively used as sentinel species in a large number of monitoring programs. However, the use of bivalves as the sole species has some limitations, because they are not as responsive as fish to Aryl Hydrocarbon Receptor agonists. Hence, for many marine areas, there is the need to validate new sentinel fish species that can be used in the assessment of pollution by organic contaminants. The shanny Lipophrys pholis is an intertidal fish that combines many characteristics required in a sentinel species: is abundant and easy to catch, has a wide geographical distribution and restrict home range. After larvae recruitment to the intertidal rocky shores, they remain in the same area for the rest of the life-cycle, thus reflecting local pollutants exposure. In order to evaluate the species sensitivity to organic contaminants under field conditions, L. pholis were collected at six sites reflecting different degrees of anthropogenic contamination. The induction of two biomarkers extensively validated in the assessment of PAHs contamination ethoxyresorufin-O-deethylase activity (EROD) and Fluorescent Aromatic Compounds (FACs) was evaluated. In parallel, mussels were collected at the same locations and levels of 16 PAHs and selected heavy metals determined. Overall, the specimens collected in the urban areas showed a significant induction of EROD and FACs (up to a six-fold induction) if compared with the reference sites. Additionally, a positive correlation was observed between the biomarkers and PAHs levels in mussel tissues. Even though further validation is currently in progress, the available data indicate that L. pholis is responsive to organic contaminants such as PAHs, suggesting its future integration in monitoring programmes designed to evaluate the presence of these contaminants in European marine ecosystems.

Bed utilization indices at a tertiary care hospital in Goa: an eight year trend analysis

A retrospective data analysis of records from medical records department of Goa Medical College Hospital was done to analyse the trends of various bed utilisation indices from 1999 - 2006. Average length of stay, bed occupancy rate, turnover interval and bed turnover ratio were the indices calculated. During the eight year period from 1999 to 2006, the average length of stay for the entire hospital registered a small decline from 6.23 to 5.51 days, the overall bed occupancy rate increased from 72.13% to 83.12% and the bed turnover interval declined from 2.41 days to 1.12 days. The Orthopaedics ward had the highest increase in bed occupancy and also fastest decline in turnover interval in 2006. Bed utilization indices are an objective measure of the efficiency of the hospital management system.

Developmental competence and expression of the Hsp 70.1 gene in oocytes obtained from Bos indicus and Bos taurus dairy cows in a tropical environment

Bos indicus cows usually have better reproductive performance in tropical and subtropical regions than Bos taurus cows, presumably due to their better adaptation to tropical environments. The aim of this study was to evaluate the developmental competence and expression of the Hsp 70.1 gene in immature oocytes from B. taurus (Holstein) and B. indicus (Gyr) dairy cows raised in a tropical region. Cumulus-oocyte complexes were obtained by transvaginal ultrasound-guided follicle aspiration between spring and early autumn, and subjected to in vitro maturation and fertilization. Presumptive zygotes were co-cultured with their own cumulus cells in CR2aa media with 10% fetal calf serum; Grade 1 blastocysts were transferred to synchronized crossbred recipients. The total RNA was extracted from immature Holstein and Gyr oocytes (three pools for each breed) and relative quantification of the Hsp 70.1 transcripts was performed by real time PCR after reverse transcription. Cleavage and blastocyst rates were greater (P<0.05) for Gyr (n=390 oocytes) than Holstein (n=505) breed (66.7% versus 53.1% of cleavage and 19.6% versus 10.8% of blastocysts, respectively), but pregnancy rates were not significantly different following transfer to recipients (44.5% for 36 Gyr embryos; 60% for 10 Holstein embryos). Holstein immature oocytes had a higher level (P<0.05) of Hsp 70.1 relative expression (1.82+/-0.22; mean+/-S.E.M.) than Gyr oocytes (1.12+/-0.11). In conclusion, Gyr oocytes obtained in a tropical region were less subject to stress and more likely to develop (after IVF) than Holstein oocytes.

Doppler assessment of uterine blood flow in recurrent pregnancy loss

OBJECTIVE

To compare uterine artery pulsatility index (PI) and flow velocity wave (FVW) patterns between women with no history of abortion and women with recurrent pregnancy loss of unexplained cause.

METHOD

A cross-sectional study was conducted with 43 women with recurrent pregnancy loss and 43 women with no history of abortion and at least 1 child born at term (control group). Transvaginal ultrasonography with uterine artery Doppler evaluation was performed in the second phase of the menstrual cycle to calculate the PI and analyze the FVW pattern.

RESULTS

The women with recurrent pregnancy loss had a significantly higher uterine artery PI than those in the control group (2.71+/-0.54 and 2.30+/-0.44, respectively), as well as a higher incidence of FVWs of the A and B types.

CONCLUSION

Compared with the control group, a higher PI and a higher incidence of FVW of the A and B types--and thus a higher uterine artery impedance--were found among women with recurrent pregnancy loss.

Eosinophil cationic protein damages protoscoleces in vitro and is present in the hydatid cyst

Eosinophils are locally recruited during the establishment and chronic phases of cystic hydatidosis. This study provides evidence that eosinophil cationic protein (ECP), one of the major components of eosinophil granules, can damage Echinococcus granulosus protoscoleces (PSC). The toxicity of ECP was investigated in vitro by following parasite viability in the presence of this protein. ECP was found to damage PSC at micromolar concentrations; the effect was blocked by specific antibodies and heparin, and was more severe than the one caused by similar concentrations of RNase A, suggesting that the cationic nature of ECP, and not its ribonuclease activity, is involved in toxicity. This observation may highlight the capacity of eosinophils to control secondary hydatidosis, derived from PSC leakage from a primary cyst. To further assess the relevance of the previous result during infection, the presence of eosinophil proteins was investigated in human hydatid cysts. ECP was found to be strongly associated with the laminated layer of the cyst wall, and present at micromolar concentrations in the hydatid fluid. Overall, these results demonstrate that eosinophils degranulate in vivo at the host-parasite interface, and that the released ECP reaches concentrations that could be harmful for the parasite.