Genomic Insights into the expansion of Carbapenem-Resistant Klebsiella pneumoniae within Portuguese Hospitals

Carbapenem-resistant Klebsiella pneumoniae complex (CR-KP) are a public health concern, causing infections with a high mortality rate, limited therapeutic options and challenging infection control strategies. In Portugal CR-KP rate has increased steeply, but the factors associated to this expansion are poorly explored. To address this question we compared, by phylogenetic and resistome analysis, the draft genomes of 200 CR-KP isolates collected in 2017-2019 from five hospitals in the Lisbon region, Portugal. We found that CR-KP belonged mainly to ST13 (29%), ST17 (15%), ST348 (13%), ST231 (12%) and ST147 (7%). Carbapenem resistance was conferred mostly by KPC-3 (74%) or OXA-181 (18%) presence, which were associated with IncF/IncN and IncX plasmids, respectively. Almost all isolates were multidrug resistant harbouring resistance determinants to aminoglycosides, beta-lactams, trimethoprim, fosfomycin, quinolones and sulphonamides. In addition, 11% of isolates were resistant to colistin. Colonizing and infection isolates were highly related and most colonized patients (89%) reported a previous hospitalization. Moreover, among the 171 events of cross-dissemination identified, by cgMLST data analysis (<5 alleles), 41 occurred between different hospitals and 130 within the same hospital. Our results suggest that CR-KP dissemination in the Lisbon region result from acquisition of carbapenemases in mobile genetic elements, influx of CR-KP into the hospitals by colonized ambulatory patients and transmission of CR-KP within and between hospitals. Our data reinforces that the prudent use of carbapenems, patients screening at hospital entrance, and improvement of infection control will be needed to decrease the burden of CR-KP infection in Portugal.

Impact of Emergency Medical System Transportation in ST-segment Elevation Myocardial Infarction: A Nationwide Retrospective Study

INTRODUCTION

Emergency medical system transportation has been shown to reduce treatment times in ST-segment elevation myocardial infarction. The authors studied the Portuguese National Registry of Acute Coronary Syndromes to determine the nationwide impact of the emergency medical system transportation in the treatment of ST-segment elevation myocardial infarction.

MATERIAL AND METHODS

A multicentric, nationwide, retrospective study of ST-segment elevation myocardial infarction patients inserted in the National Registry from 2010 to 2017 was performed. The patients were divided into: Group I, composed of patients transported by emergency medical system, and Group II, patients arriving to the Emergency department by other means.

RESULTS

Of the 5702 patients studied, 25.9% were transported via emergency medical system. Rates of emergency medical system activation increased by 17% in the last 7 years. The emergency medical system provided a higher rate of transport to a percutaneous coronary intervention capable centre, of Emergency department bypass, of on-site fibrinolysis, and ensured a 59-minute reduction of the median reperfusion time (p < 0.001). There was no difference in in-hospital mortality.

DISCUSSION

In this nationwide cohort, emergency medical system transportation is associated with a reduction in reperfusion times. It provides a higher amount of salvaged myocardium and reduces the incidence of acute heart failure. However, emergency medical system use did not result in lower in-hospital mortality, probably due to confounding factors of higher disease severity and comorbidity.

CONCLUSION

The benefits associated with emergency medical system based transportation of patients with ST-segment elevation myocardial infarction do not translate into lower in-hospital mortality.

Epidemiology of Carbapenemase-Producing Klebsiella pneumoniae in a Hospital, Portugal

We aimed to provide updated epidemiologic data on carbapenem-resistant Klebsiella pneumoniae in Portugal by characterizing all isolates (N = 46) recovered during 2013–2018 in a 123-bed hospital in Lisbon. We identified bla_KPC-3 (n = 36), bla_OXA-181 (n = 9), and bla_GES-5 (n = 8) carbapenemase genes and observed co-occurrence of bla_KPC-3 and bla_GES-5 in 7 isolates. A single GES-5–producing isolate co-produced the extended-spectrum β-lactamase BEL-1; both corresponding genes were co-located on the same ColE1-like plasmid. The bla_OXA-181 gene was always located on an IncX3 plasmid, whereas bla_KPC-3 was carried on IncN, IncFII, IncFIB, and IncFIIA plasmid types. The 46 isolates were distributed into 13 pulsotypes and 9 sequence types. All isolates remained susceptible to ceftazidime/avibactam, but some exhibited reduced antimicrobial susceptibility (MIC = 3 mg/L).

Application of Risks Scores in Acute Coronary Syndromes. How Does ProACS Hold Up Against Other Risks Scores?

BACKGROUND

Multiple risk scores (RS) are approved in the prediction of worse prognosis in acute coronary syndromes (ACS). Recently, the Portuguese Journal of Cardiology has proposed the ProACS RS.

OBJECTIVE

Application of several validated RS, as well as ProACS in patients, admitted for ACS. Evaluation of each RS's performance in predicting in-hospital mortality and the occurrence of all-cause mortality or non-fatal ACS at one-year follow-up and compare them to the ProACS RS.

METHODS

A retrospective study of ACS was performed. The following RS were applied: GRACE, ACTION Registry-GWTG, PURSUIT, TIMI, EMMACE, SRI, CHA2DS2-VASc-HS, C-ACS and ProACS. ROC Curves were created to determine the predictive power for each RS and then were directly compared to ProACS.

RESULTS

The ProACS, ACTION Registry-GWTG and GRACE showed a c-statistics of 0.908, 0.904 and 0.890 for predicting in-hospital mortality, respectively, performing better in ST-segment elevation myocardial infarction patients. The other RS performed satisfactorily, with c-statistics over 0.750, apart from the CHA2DS2-VASc-HS and C-ACS which underperformed. All RS underperformed in predicting worse long-term prognosis revealing c-statistics under 0.700.

CONCLUSION

ProACS is an easily obtained risk score for early stratification of in-hospital mortality. When evaluating all RS, the ProACS, ACTION Registry-GWTG and GRACE RS showed the best performance, demonstrating high capability of predicting a worse prognosis. ProACS was able to demonstrate statistically significant superiority when compared to almost all RS. Thus, the ProACS has showed that it is able to combine simplicity in the calculation of the score with good performance in predicting a worse prognosis.

Improvement in soil and sorghum health following the application of polyacrylate polymers to a Cd-contaminated soil

Contamination of soils with cadmium (Cd) is a serious global issue due to its high mobility and toxicity. We investigated the application of insoluble polyacrylate polymers to improve soil and plant health. Sorghum was grown in a Cd-contaminated sandy soil. Polyacrylate polymers at 0.2% (w/w) were added to half of the soil. Control soil without plants was also included in the experiment. Growth of sorghum was stimulated in the polymer-amended soil. The concentration of Cd in the shoots, and the activities of catalase and ascorbate peroxidase decreased in plants from polymer-amended soil compared with unamended control. The amount of CaCl(2)-extractable Cd in the polymer-amended soil was 55% of that in the unamended soil. The Cd extracted in sorghum shoots was 0.19 mg per plant grown on soil without polymer and 0.41 mg per plant grown on polymer-amended soil. The total amount of Cd removed from each pot corresponded to 1.5 and more than 6% of soil CaCl(2)-extractable Cd in unamended and polymer-amended soil, respectively. The activities of soil acid phosphatase, beta-glucosidase, urease, protease and cellulase were greatest in polymer-amended soil with sorghum. In conclusion, the application of polyacrylate polymers to reduce the bioavailable Cd pool seems a promising method to enhance productivity and health of plants grown on Cd-contaminated soils.

Thermodynamics of uptake of cadmium by Chlorella marina

From voltammetric titration curves of living Chlorella marina cells with cadmium ion, at constant pH, the surface binding capacity of the alga was determined and interpreted in terms of average conditional equilibrium constants and of differential equilibrium function. Since the alga can live in estuaries, the influence of ionic strength and competition of alkaline and alkaline earth cations has been considered. Cadmium complexation with dead algae killed by heat or using formaldehyde has also been studied for comparison.

Adenosine A2A receptors facilitate 45Ca2+ uptake through class A calcium channels in rat hippocampal CA3 but not CA1 synaptosomes

In the hippocampus, the neuromodulatory role of adenosine depends on a balance between inhibitory A1 responses and facilitatory A2A responses. Since the presynaptic effects of hippocampal inhibitory A1 adenosine receptors are mostly mediated by inhibition of Ca2+ channels, we now investigated whether presynaptic facilitatory A2A adenosine receptors would modulate calcium influx in the hippocampus. The mixed A1/A2 agonist, 2-chloroadenosine (CADO; 1 microM) inhibited veratridine (20 microM)-evoked 45Ca2+ influx into hippocampal synaptosomes of the CA1 or CA3 areas by 24.2 +/- 4.5% and 17.2 +/- 5.8%, respectively. In the presence of the A, antagonist, 1,3-dipropyl-8-cyclopentylxanthine (DPCPX; 100 nM), the inhibitory effect of CADO (1 microM) on 45Ca2+ influx was prevented in CA1 synaptosomes, but was converted into a facilitatory effect (14.2 +/- 6.7%) in CA3 synaptosomes. The A2A agonist, CGS 21680 (3-30 nM) facilitated 45Ca2+ influx in CA3 synaptosomes, with a maximum increase of 22.9 +/- 3.9% at 10 nM, and was virtually devoid of effect in CA1 synaptosomes. This facilitatory effect of CGS 21680 (10 nM) in CA3 synaptosomes was prevented by the A2A antagonist 8-(3-chlorostyryl)caffeine (CSC; 200 nM), but not by the A1 antagonist, DPCPX (20 or 100 nM). The facilitatory effect of CGS 21680 on 45Ca2+ uptake by CA3 synaptosomes was prevented by the class A calcium channel blocker, omega-agatoxin-IVA (200 nM). These results indicate that presynaptic adenosine A2A receptors facilitate calcium influx in the CA3 but not the CA1 area of the rat hippocampus through activation of class A calcium channels.

[Prognostic factors in intraparenchymatous cerebral hemorrhages. An analysis of a hospitalization series]

We studied 76 patients, with the diagnosis of spontaneous intracerebral haematoma confirmed by CT scan, admitted to the Internal Medicine Department of S. Pedro Hospital, Vila Real, from 1991 to 93. Neurologic examination, radiological characteristics, previous diseases, clinical evolution and treatment were analysed to select prognostic factors in relation to length of stay, functional status and mortality. Length of stay varied between 1 and 63 days and it is estimated that 50% of these patients have a length of stay of less than 22 days. In what concerns length of stay, the localisation of haematoma (p < 0.001) and presence/absence of systemic infections (p < 0.001) were the most significant prognostic factors. The haematomas localised in the brain stem or cerebral deep massive and the occurrence of systemic complications were associated to a longer hospital stay. None of the parameters analysed were related to functional status (Rankin scale), despite the fact that functional impairment was present in 57.1% of the patients whose hemorrhage had ventricular blood, compared with 27.5% whose hemorrhage had no ventricular blood. In this series, the mortality rate was 29.2% and the presence/absence of ventricular blood was the most important prognostic factor (p < 0.001). The mortality rate in patients whose haematoma presented ventricular blood was five times higher than in the remainder.

Adenosine A2 receptor activation facilitates 45Ca2+ uptake by rat brain synaptosomes

Adenosine has been shown to increase the release of neurotransmitters by stimulation of adenosine A2 receptors. This effect probably depends on Ca2+ entry into presynaptic nerve terminals. In the present work the ability of the mixed adenosine A1/A2 agonist, 2-chloroadenosine, to stimulate Ca2+ uptake into rat brain synaptosomes was investigated. 45Ca2+ uptake was induced by 20 microM veratridine. In the absence of other drugs, 2-chloroadenosine (1 microM) decreased 45Ca2+ uptake into synaptosomes. Blocking the adenosine A1 receptor with 100 nM of 1,3-dipropyl-8-cyclopentylxanthine (DPCPX), 2-chloroadenosine (1 microM) increased rather than decreased the uptake of 45Ca2+ into synaptosomes. The excitatory effect of 2-chloroadenosine observed in the presence of DPCPX was reversed by 200 nM of omega-agatoxin-IVA, a specific P-type Ca2+ channel antagonist, but not by L-type (nifedipine, 100 nM to 1 microM; methoxyverapamil 1-10 microM) or N-type (omega-conotoxin GVIA, 500 nM) Ca2+ channel antagonists. The adenosine A2A selective agonist 2-p-(2-carboxyethyl)-phenethylamino-5'-N-ethyl-carboxamido-adenosi ne (CGS 21680), did not significantly modify Ca2+ uptake induced by veratridine. In contrast, the selective adenosine A2 receptor agonist, N6-(2-(3,5-dimethoxyphenyl)-2-(2-methylphenyl)ethyl)-adenosine (DPMA), in concentrations ranging from 10 nM to 1 microM increased Ca2+ uptake induced by veratridine. The selective adenosine A2 receptor antagonist 3,7-dimethyl-1-propargylxanthine (DMPX) at a concentration of 10 microM antagonized the stimulatory effect of DPMA (0.1 microM) on 45Ca2+ uptake. In conclusion, activation of adenosine A2 receptors increases Ca2+ uptake by synaptosomes depolarized by veratridine, which could explain the increase of neurotransmitter release observed when A2 receptors are activated.

Uptake of lead and its influence in the alga Selenastrum capricornutum printz

The influence of nutrient level, hours of fight and the flux of air by volume of solution on uptake of lead has been examined from batch growth experiments carried out with the alga Selenastrum capricornutum Printz. The organic matter released by the alga has been characterized in terms of absorbance at 285 nm, dissolved organic carbon and maximum intensity of fluorescence at the excitation peak. The lability of lead complexes formed with the alga exudates has been investigated in terms of differential pulse anodic stripping voltammetry (DPASV). It has been noticed that lead inhibits the division of the cells which become bigger in size but with less pigment per cell.

Effect of adenosine on 45Ca2+ uptake by electrically stimulated rat brain synaptosomes

The effect of adenosine on 45Ca2+ uptake by rat brain synaptosomes stimulated by electrical pulses was investigated. 45Ca2+ uptake was voltage dependent. Adenosine (1 nM-1 microM) decreased the uptake of 45Ca2+ induced by electrical stimulation (amplitude, 20 V; duration, 400 microseconds; frequency, 10 pulses/s) in a concentration-dependent manner. At a concentration of 1 microM, adenosine almost abolished the 45Ca2+ uptake induced by electrical stimulation (92.9 +/- 5.3% inhibition), but when the calcium uptake was induced by high-K+ (60 mM) medium, the effect of adenosine (1 microM) was smaller (43.8 +/- 5.2% inhibition). The inhibitory effect of 1 microM adenosine on calcium uptake induced by electrical stimulation was antagonized by 1,3-dipropyl-8-p-sulfophenylxanthine (5 microM). The possibility that adenosine interacts with the calcium channels opened by electrical stimulation is discussed.

Effects of purines and forskolin on haemolysis

Effects of adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), and adenosine on the antihaemolytic action of procaine, and the effect of ATP on the antihaemolytic actions of lidocaine, dibucaine, tetracaine, pentobarbitone, and chlorpromazine were investigated in rat erythrocytes. The effects of adenosine and its analogues D-N6-phenylisopropyladenosine (D-PIA), L-N6-phenylisopropyladenosine (L-PIA), N6-cyclohexyladenosine (CHA), 2-chloroadenosine, and N6-methyladenosine, as well as the effects of cyclic-AMP (cAMP), dibutyryl cAMP, and forskolin on haemolysis were also investigated in rat erythrocytes. ATP, ADP, and AMP, but not adenosine, antagonized in a concentration-dependent manner the antihaemolytic action of procaine, and ATP was ineffective against the antihaemolytic actions of lidocaine, dibucaine, tetracaine, pentobarbitone, and chlorpromazine. Adenosine and its analogues, but not N6-methyladenosine, protected erythrocytes against hypotonic haemolysis in a concentration-dependent manner. The order of potencies was: D-PIA greater than CHA greater than L-PIA greater than adenosine greater than 2-chloroadenosine. The effect of adenosine on haemolysis was not prevented by theophylline, 8-phenyltheophylline, or 8-sulfophenyltheophylline. Dibutyryl cAMP, a stable analogue of cAMP, and forskolin, a specific activator of adenylate cyclase, mimicked the antihaemolytic action of adenosine. cAMP was less efficient than adenosine. Adenine nucleotides antagonized the antihaemolytic action of procaine, probably due to calcium-chelating properties. In contrast, adenine nucleosides have antihaemolytic properties. The possibility that the antihaemolytic effects of these substances relate to cAMP and/or to lipophilicity is discussed.

Influence of serum proteins on erythrocyte uptake of digoxin and digitoxin

My purpose was to find out whether changes in serum protein content (albumin and gamma globulin) influenced erythrocyte uptake of glycosides and the capacity of erythrocytes to equilibrate glycoside levels when there are changes in protein binding. Heparinized human blood was incubated with 3H-digoxin, 6 ng/ml, and 3H-digitoxin, 44 ng/ml for 15 min. After centrifugation, distribution between plasma and erythrocytes was determined by liquid scintillation. Ratios between erythrocyte and plasma concentrations were 0.84 and 0.11 for digoxin and digitoxin. Replacing plasma by a protein-free isotonic solution led to increased erythrocyte uptake by 15% and 540% for digoxin and digitoxin. Erythrocyte uptake for both drugs was also determined in varying amounts of albumin (0 to 120 gm/l) and gamma globulin (0 to 25 gm/l). Only albumin influenced the erythrocyte uptake of these drugs. Calculations of free and bound plasma levels for both drugs showed that free digitoxin increased when albumin concentrations were equal to or less than 10 gm/l and remained constant (3%) for albumin concentrations between 15 and 120 gm/l. Free digoxin plasma levels rise when the albumin concentration is equal to or less than 15 gm/l and do not change at albumin levels between 30 and 120 gm/l. These data indicate that blood components play an important role in equilibrating changes in free digoxin and digitoxin levels.