Photodegradation of 2,4-D (dichlorophenoxyacetic acid) with Rh/TiO2; comparative study with other noble metals (Ru, Pt, and Au)

In this work the effect of noble metal on the photodegradation of 2,4-dichlorophenoxyacetic acid herbicide using TiO₂ as support was studied. The metals and concentration were: Rh, Ru, Pt and Au and 1, 0.98, 1.89, and 1.91 wt% respectively. Rhodium was taken as reference for this experiment. The samples were characterized by X-Ray Diffraction (XRD), UV-vis absorption spectra, N₂ physisorption (BET Specific Surface Area), High Annular Angle Analysis Darkfield (HAADF) and Transmission Electron Microscopy Scanning (STEM), H₂ chemisorption, optical emission spectroscopy with inductive coupling plasma analysis (ICP-OES), solid fluorescence, X-ray Photoelectron Spectroscopy (XPS) and OH quantification. The presence of the anatase crystalline phase was mostly confirmed in all samples. The band gap decreased with the presence of metal (from 3.24 to 2.92 eV). The specific area was a function of the metal particle size. The metal particle diameter showed the following sequence Pt > Ru > Au > Rh. By XPS, TiO₂ does not manifest changes in oxidation states, but when impregnated with metals, only Pt shows the highest abundance of any oxidized state (Pt²⁺). The presence of metal reveals less electron–hole recombination compared with titanium oxide. The results of photocatalytic activity showed that Pt and Rh are the two metals with the highest mineralization (99.0 and 98.3%, respectively).

The optimum catalyst for the photocatalytic degradation of 2,4-D was Rh (1%)/TiO₂ by UV radiation. The Rh presents a strong metal-support interaction and improves the photocatalytic properties of TiO₂, modifying its band gap energy.

Assessment of the CHA2DS2-VASc score in predicting ischemic stroke and death in patients with acute myocardial infarction without atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

onbehalf

on behalf of the investigators of the Portuguese Registry of Acute Coronary Syndromes

Introduction

The CHA2DS2-VASc score is used in clinical practice to stratify the risk of stroke in patients (pts) with atrial fibrillation (AF). Its usefulness in the population of pts with acute myocardial infarction without AF is not well known.

Objectives

To investigate whether CHA2DS2-VASc predicts ischemic stroke and death during hospital stay in pts with acute myocardial infarction without known AF. To determine independent predictors of ischemic stroke in this population.

Methods

A multicentre, retrospective study was performed during 01/10/2010-04/09/2019 period, and included all pts admitted due to acute myocardial infarction. Pts with previous AF, AF rhythm in the electrocardiogram at admission or AF during hospital stay were excluded. Statistical analysis with Kaplan-Mayer and Cox regression was applied.

Results

Of 29851 pts admitted with acute myocardial infarction, were included in our study 19218 pts (74% male, mean age of 65 ± 14 years). 

During hospital stay, 78 (0.4%) pts had an ischemic stroke and 462 (2.4%) pts died. 

The event-free survival analysis showed significant differences according to the CHA2DS2-VASc score at admission (log rank test p = 0.015 for ischemic stroke; log rank test p < 0.001 for in-hospital mortality). (Figure) 

The CHA2DS2-VASc score demonstrated a good predictive accuracy for in-hospital mortality (area under the ROC curve 0.69; 95% CI 0.67-0.72; p < 0.001). The area under the ROC curve indicates that the CHA2DS2-VASc score performed modestly for ischemic stroke (0.62; 95% CI 0.56-0.68; p < 0.001). 

In univariate analysis, the factors that were positively associated with ischemic stroke during hospital stay were CHA2DS2-VASc, absence of previous therapy with statin, time between cardiac symptoms and hospital admission, absence of chest pain, Killip-Kimball class, cardiorespiratory arrest, complete left ventricular block and left ventricle ejection fraction <50% (p < 0.05). 

After multivariate analysis, CHA2DS2-VASc≥3 (HR 2.25; 95% CI 1.37-3.71; p = 0.001), absence of chest pain (HR 3.17; CI 1.44-6.14, p < 0.001) and previous therapy with statin (HR 0.39; 95% CI 0.22-0.67; p = 0.001) were independent predictors of ischemic stroke.

Conclusion

 Among patients with acute myocardial infarction without known atrial fibrillation, the CHA2DS2-VASc score was associated with risk of ischemic stroke and death during hospital stay. This score may be useful for estimating the risk of stroke and in-hospital mortality in these population without known atrial fibrillation.

Abstract Figure.

The 90s are the new 70s: approach to nonagenarian patients with myocardial infarction: data from the Real World Portuguese Registry on Acute Coronary Syndromes (ProACS)

Introduction

The approach to Acute Coronary Syndromes is based on robust high quality evidence, currently systematized in European endorsed guidelines. However most trials that support such guidelines excluded or included a small percentage of the very elderly, namely nonagenarian patients, and the clinical decision in this age range is subjected to high interpersonal and inter-hospital variability.

Purpose

Our aim was to assess the approach to nonagenarian patients with Acute Coronary Syndromes (ACS), in what regards the choice of percutaneous coronary intervention or conservative management and determine in-hospital and at 1 year outcomes.

Methods

We performed a 9 year retrospective analysis of all patients with age equal or greater than ninety (90) admitted with ACS in Portugal. Medical records were analysed for demographic, procedural data and outcomes.

Results

Seven hundred and fourteen (714) nonagenarian patients were admitted with ACS, which corresponded to 2.4% of the total cohort. The mean age was 92±2 with a female preponderance (58.7%). There was a high rate of cardiovascular risk factor with hypertension in 81.3%; Dyslipidemia in 46.1% Diabetes Mellitus in 23.4%; and other comorbidities with 21% of prior ACS, 14.4% with Heart Failure, 11% with cerebrovascular events and 15.4% with chronic kidney failure.

The ACS was categorized as ST elevation Myocardial Infarction (STEMI) in 43.9%, non- STEMI (NSTEMI) in 45.8%, and unstable angina (UA) in 2%.

Two hundred and sixty-eight (268), 37.8% of the cohort, were submitted to percutaneous coronary intervention (PCI), mainly due to STEMI (68.3%). This cohort were composed of patients with less comorbidities (statistically significant less valvular heart disease, heart failure, peripherical artery disease and dementia although more oncological diseases). There was no difference in the severity of ACS, as categorized by the Kilip Kimbal (KK) classification, mechanical complication or depressed ejection fraction between the 2 groups. (p>0.05 for all)

There was a statistically significant increase of advanced atrioventricular block (10.6 vs 4.4%; p 0.002; Logistic regression OR 3.12; IC95 [1.37–7.15], p 0.007) and major bleeding (1.8 vs 5.5%; p 0.008; Logistic regression OR 3.36; IC95 [1.36–8.32] p 0.009) in the PCI group. There was no difference in in-hospital re-infarction, cardiac arrest, stroke or death. (p>0.05 for all)

The follow up at 1 year was performed in two hundred and fifty-six (256) patients, 30.9% submitted to PCI. Although the survival analysis demonstrated a trend towards improvement in 1-year survival and cardiovascular readmissions in the intervention group, it did not reach statistical significance. (p>0.05 for all)

Conclusions

PCI was performed in about a third of nonagenarians presenting with ACS. Our cohort demonstrated a greater rate of in-hospital complications without a significant in-hospital or at 1 year clinical benefit.

Funding Acknowledgement

Type of funding source: None

P846Discriminatory power of the grace score in non-ST segment elevation myocardial infarction in the real world: results from the portuguese registry on acute coronary syndromes

Introduction

Current clinical practice guidelines recommend risk stratification in patients with acute coronary syndrome (ACS) upon admission to the hospital. The Global Registry of Acute Coronary Events (GRACE) risk score was developed in a large multinational registry to predict both mortality and the combined events of death or reinfarction during the hospital stay and 6 months after discharge. Given the substantial regional variation and temporal changes in patient characteristics and management patterns, specially in non-ST segment elevation myocardial infarction (NSTEMI) patients, we sought to validate this risk score in a contemporary Portuguese population.

Purpose

To assess the discriminatory power of the GRACE risk score in a Portuguese contemporary cohort of patients with NSTEMI submitted to invasive strategy, regarding in-hospital mortality and the combined end-point of reinfarction and/or in-hospital mortality.

Methods

We included patients with NSTEMI submitted to coronary angiogram from the Portuguese Registry on Acute Coronary Syndrome (ProACS). For each patient, we calculated the GRACE risk score and classified them in low, intermediate or high risk, according to the cut-offs recommended in the guidelines. The discriminatory capacity of the GRACE risk score was evaluated by the area under the receiver operating characteristic [ROC] curve. The primary endpoint was defined as the occurrence of reinfarction and in-hospital mortality, and the secondary endpoint was in-hospital mortality.

A model with an AUC-ROC between 0.8 and 0.9 was considered to have a good capacity for discrimination.

Results

Among the 19.430 patients included in the ProACS between October 2010 and January 2019, we identified 7304 patients with NSTEMI that performed coronary angiogram and had the GRACE score calculated (37.6%). Patients were divided in three groups according to the GRACE score (group 1: 1–108; group 2: 109–140; group 3: 141–372), with 24.9% included in group 1, 33.0% in group 2, and 42.1% in group 3. Most patients were male (73.4%), with a mean age of 66±12 years, and 48.0% were admitted to non-percutaneous coronary intervention centers. In-hospital mortality was 1.0% and the primary endpoint occurred in 2.2% of the patients. The discriminatory capacity of the GRACE score in our population was good regarding in-hospital mortality: the area under the ROC curve was 0.83 (95% confidence interval [CI], 0.783–0.878), with the best cut-off of 148. The discriminatory capacity for the primary end-point was reasonable; the area under the ROC curve was 0.700 (95% CI 0.654–0.745), and the best cut-off was 164.

Conclusions

In our population of patients with NSTEMI submitted to an invasive strategy, the GRACE risk score presented a moderate discriminatory capacity for the occurrence of reinfarction and in-hospital, and a a good discriminatory power for in-hospital mortality.

P3128Unprotected left main revascularization in patients with acute myocardial infarction: insights of a multicenter national registry

Introduction

Unlike stable coronary disease, there is no consensus about the best revascularization strategy for unprotected left main coronary artery (ULMCA) disease associated with acute myocardial infarction (MI). Recent studies have shown that percutaneous coronary intervention (PCI) is technically feasible with acceptable outcomes, making it a reasonable alternative to surgical revascularization (CABG).

Aims

To describe the practice of ULMCA revascularization in MI patients (pts) and its evolution over an 9-year period. To analyze the prognosis of this population and determine the effect of revascularization on outcome.

Methods

Retrospective, multicenter national observational study that included 19 430 MI pts from October 2010 to December 2018. Pts who presented ULMCA as culprit lesion were selected and then compared the subgroup that underwent revascularization by PCI alone versus (vs.) CABG alone. Primary endpoint (PE) was a composite of all-cause death, nonfatal re-MI and nonfatal stroke during hospital stay. Secondary endpoint (SE) was all-cause death rate at 1-year after hospital discharge.

Results

204 pts with ULMCA as culprit lesion were selected (1.1% of all pts): 77.9% male, mean age 69±12 years, 97 (47.5%) underwent CABG alone, 92 (45.1%) PCI alone, 10 (4.9%) no revascularization and 5 (2.5%) both strategies. At admission, pts undergoing PCI alone presented more frequently with ST-segment elevation, persistent chest pain, cardiogenic shock and higher values of GRACE risk score. During hospital stay, severe left ventricular (LV) systolic dysfunction (<30%), need for mechanical ventilation, sustained ventricular tachycardia and aborted cardiac sudden death were also more common in these pts. Concerning PE, global rate was 18.5% (27 deaths, 6 nonfatal re-MI and 2 nonfatal stroke). It was significantly higher in pts undergoing PCI alone (32.6% vs. 3.1%, p<0.01). After adjustment, surgical revascularization had 98% lower odds of PE occurrence compared to PCI (OR 0.02, 95% CI 0.002–0.22, p<0.01). Cardiogenic shock at admission (OR 5.06, 95% CI 1.21–21.11, p=0.03) and severe LV systolic dysfunction (OR 7.77, 95% CI 1.49–40.56, p=0.02) were also independent predictors of adverse outcome. One-year all-cause death rate was 4.9%, with no significant difference at survival curves between PCI vs. CABG (Log-Rank p=0.96).Over the 9-year, there was not a significant change in the use of one revascularization technique over the other.

Conclusions

MI with ULMCA as culprit lesion is infrequent and associated with a high rate of adverse events during hospital stay. PCI was preferred in higher risk pts but, even after adjustment, it was associated with a less favorable short-term outcome compared to surgical strategy. Nevertheless, long-term prognosis was excellent in hospital survivors with no difference between both techniques. Randomized trials are needed to determine the ideal revascularization strategy for these pts.

P6403Predictors of bleeding in elderly patients with myocardial infarction: data from the real world

Background

The population of elderly patients with acute myocardial infarction (MI) is clearly underrepresented in contemporary clinical trials. This population presents a higher risk of both cardiovascular and bleeding events, making the decision of the antithrombotic strategy particularly challenging.

Purpose

To characterize the antithrombotic therapy used in patients with MI and age ≥75 years, and to identify predictors of major bleeding and cardiovascular events in this population.

Methods

Retrospective analysis of patients with a diagnosis of MI and age ≥75 years included in the Portuguese Registry of Acute Coronary Syndromes between October 2010 and January 2018. Logistic regression analysis was used to identify predictors of major bleeding and of the combined endpoint of in-hospital mortality and reinfarction.

Results

The analysis included 17.868 patients of which 30.1% with age ≥75 years. This population had a mean age of 82±5 years, 57% were male and 36% had a diagnosis of STEMI. On admission 10% presented with Killip-Kimball (KK) class III or IV, 14% were on atrial fibrillation (AF), and the mean Hb and creatinine levels were 13±2 g/dl and 1.6±1.2 mg/dl, respectively. In comparison with younger patients, this population had higher Grace and Crusade scores (178 vs 139, and 41 vs 24, respectively). Most elderly patients (74%) underwent coronary angiography (71% by radial artery access) and 75% were submitted to percutaneous revascularization, 9% to surgery, and 1% to an hybrid strategy. Aspirin was used in 96% of patients, clopidogrel in 82%, ticagrelor in 13% (vs 25% of younger patients; p<0.001), and glycoprotein IIb/IIIa inhibitors (GPI) in 11%. Most patients were anticoagulated with enoxaparin (68 vs 56% of younger patients; p<0.001), 22% with unfractionated heparin (vs 30%; p<0.001), and 13% with fondaparinux (vs 14%; p=0.018). Complications were more common in the elderly population, including mechanical complications (1 vs 0.5%), atrioventricular block (5 vs 3%), stroke (1 vs 0.6%), major bleeding (3 vs 1%), in-hospital death (8 vs 2%) and reinfarction (2 vs 1%) (p<0.001 for all).

In multivariate logistic regression analysis, the predictors of major bleeding were diastolic blood pressure (BP) on admission <50 mmHg, maximum creatinine ≥2 mg/dl and the use of GPI. The predictors of the combined endpoint were a diagnosis of STEMI, previous history of cancer, chronic kidney disease or demencia, and the presence on admission of an heart rate <60 bpm, systolic BP <90 mmHg or ≥180 mmHg, KK class > I, AF, left bundle branch block, and left ventricle systolic dysfunction.

Conclusions

This study reflects the contemporary national reality of the management of elderly patients with MI. Overall, this population has a high risk of major bleeding, but several characteristics are associated with an even higher risk, such as the hemodynamic profile, renal function, and the use of GPI.

The relationship between faecal-associated and mucosal-associated microbiota in irritable bowel syndrome patients and healthy subjects

BACKGROUND

The faecal-associated microbiota is commonly seen as a surrogate of the mucosal-associated microbiota. However, previous studies indicate that they are different. Furthermore, analyses of the mucosal microbiota are commonly done after standard bowel cleansing, affecting the microbial composition.

AIM

To compare the mucosal-associated microbiota, obtained from unprepared colon, with faecal-associated microbiota in healthy subjects and irritable bowel syndrome (IBS) patients.

METHODS

Faecal and mucosal biopsies were obtained from 33 IBS patients and 16 healthy controls. Of IBS patients, 49% belonged to the diarrhoea-predominant subgroup and 80% suffered from IBS symptoms during at least 5 years. Biopsies were collected from unprepared sigmoid colon and faecal samples a day before colonoscopy. Microbiota analyses were performed with a phylogenetic microarray and redundancy discriminant analysis.

RESULTS

The composition of the mucosal- and the faecal-associated microbiota in unprepared sigmoid colon differs significantly (P = 0.002). Clinical characteristics of IBS did not correlate with this difference. Bacteroidetes dominate the mucosal-associated microbiota. Firmicutes, Actinobacteria and Proteobacteria dominate the faecal-associated microbiota. Healthy subjects had a significantly higher (P < 0.005) abundance (1.9%) of the bacterial group uncultured Clostridiales I in the mucosal-associated microbiota than IBS patients (0.3%). Bacterial diversity was higher in faecal- compared with mucosal-associated microbiota in IBS patients (P < 0.005). No differences were found in healthy subjects.

CONCLUSIONS

Differences in the mucosal-associated microbiota between healthy individuals and IBS patients are minimal (one bacterial group) compared to differences in the faecal microbiota of both groups (53 bacterial groups). Microbial aberrations characterising IBS are more pronounced in the faeces than in the mucosa.

Altered faecal and mucosal microbial composition in post-infectious irritable bowel syndrome patients correlates with mucosal lymphocyte phenotypes and psychological distress

BACKGROUND

A subset of irritable bowel syndrome (IBS) patients, denoted post-infectious IBS (PI-IBS), develop symptoms after an enteric infection. Bacterial dysbiosis and mucosal inflammation have been proposed to be involved in the pathophysiology of this entity.

AIM

To characterise the mucosal and faecal microbiota in PI-IBS, general IBS and healthy controls, and to investigate associations between the microbiota and the mucosal immune system.

METHODS

Mucosal biopsies and faeces were collected from 13 PI-IBS patients, 19 general IBS patients and 16 healthy controls. Global bacterial composition was determined by generating 16S rRNA amplicons that were examined by phylogenetic microarray hybridisation, principal component and redundancy analysis. We correlated previously reported lymphocyte proportions with the microbiota.

RESULTS

Faecal microbiota composition of PI-IBS patients differed significantly from both general IBS patients and healthy controls (P < 0.02). Both mucosal (P < 0.01) and faecal (P = 0.05) microbial diversity were reduced in PI-IBS compared to healthy controls. In the intraepithelial lymphocytes the previously published proportion of CD8(+) CD45RA(+) was negatively correlated with mucosal microbial diversity (P < 0.005). The previously published number of lamina propria lymphocytes was negatively correlated with mucosal microbial diversity (P < 0.05). Faecal microbial diversity was significantly negatively correlated with the Hospital Anxiety and Depression scale (P < 0.05).

CONCLUSIONS

We present data that distinguishes the intestinal microbiota of PI-IBS patients from that of both general IBS patients and HC. The microbial composition is significantly associated with the HADs score and alterations in lymphocyte subsets proportions.