Prevalence of anti-beta-1 antibody 6 months after hospitalization for acute heart failure predicts adverse outcome

AIMS

Agonistic antibodies against neurohumoral receptors can induce cardio-noxious effects by altering the baseline receptor activity. To estimate the prevalence of autoantibodies directed against the beta-1 receptor (b1-AAB) in patients admitted to the hospital for acute heart failure (HF) at (i) baseline and (ii) after 6 months of follow-up (F6) and (iii) after another 12 months of follow-up (i.e. 18 months after index hospitalization), to estimate their prognostic impact on clinical outcome (death or first hospitalization for HF).

METHODS AND RESULTS

In 47 patients, b1-AAB were serially determined in serum samples collected at index hospitalization and at 6 months of follow-up (F6) with a flow cytometry-based assay: median age 71 years (quartiles 60, 80), 23 (49%) women, 24 (51%) HF with preserved ejection fraction. Beta1-AAB were detected in three subjects at index hospitalization (6%), and in eight subjects at F6 (17%). There were no differences apparent between patients with and without b1-AAB at F6 with regard to age, sex, type, duration, or main cause of HF. During the 12 month period following F6 (i.e. up to month 18), eight events occurred. Event-free survival was associated with prevalence of b1-AAB at F6. Compared with patients without b1-AAB at F6, age-adjusted Cox regression indicated a higher event risk in patients harbouring b1-AAB, with a hazard ratio of 8.96 (95% confidence interval 1.81-44.50, P = 0.007).

CONCLUSIONS

Our results suggest a possible adverse prognostic relevance of b1-AAB in patients with acute HF, but this observation needs to be confirmed in larger patient collectives.

Current status and future challenges in implementing and upscaling vertical farming systems

Vertical farming can produce food in a climate-resilient manner, potentially emitting zero pesticides and fertilizers, and with lower land and water use than conventional agriculture. Vertical farming systems (VFS) can meet daily consumer demands for nutritious fresh products, forming a part of resilient food systems-particularly in and around densely populated areas. VFS currently produce a limited range of crops including fruits, vegetables and herbs, but successful implementation of vertical farming as part of mainstream agriculture will require improvements in profitability, energy efficiency, public policy and consumer acceptance. Here we discuss VFS as multi-layer indoor crop cultivation systems, exploring state-of-the-art vertical farming and future challenges in the fields of plant growth, product quality, automation, robotics, system control and environmental sustainability and how research and development, socio-economic and policy-related institutions must work together to ensure successful upscaling of VFS to future food systems.

Sparse identification of nonlinear dynamics for model predictive control in the low-data limit

Data-driven discovery of dynamics via machine learning is pushing the frontiers of modelling and control efforts, providing a tremendous opportunity to extend the reach of model predictive control (MPC). However, many leading methods in machine learning, such as neural networks (NN), require large volumes of training data, may not be interpretable, do not easily include known constraints and symmetries, and may not generalize beyond the attractor where models are trained. These factors limit their use for the online identification of a model in the low-data limit, for example following an abrupt change to the system dynamics. In this work, we extend the recent sparse identification of nonlinear dynamics (SINDY) modelling procedure to include the effects of actuation and demonstrate the ability of these models to enhance the performance of MPC, based on limited, noisy data. SINDY models are parsimonious, identifying the fewest terms in the model needed to explain the data, making them interpretable and generalizable. We show that the resulting SINDY-MPC framework has higher performance, requires significantly less data, and is more computationally efficient and robust to noise than NN models, making it viable for online training and execution in response to rapid system changes. SINDY-MPC also shows improved performance over linear data-driven models, although linear models may provide a stopgap until enough data is available for SINDY. SINDY-MPC is demonstrated on a variety of dynamical systems with different challenges, including the chaotic Lorenz system, a simple model for flight control of an F8 aircraft, and an HIV model incorporating drug treatment.

International Normalized Ratio (INR) – Proficiency Tests by ÖQUASTA for the Prothrombin Time

Although the INR (International Normalized Ratio)/ISI (International Sensitivity Index) scheme was introduced by the WHO (13) in 1983 to standardize the PT (prothrombin time) expression, the use of the non-comparable percent of a normal fresh plasma, seconds or PT-ratio (patient plasma/normal plasma) is still common in the coagulation laboratories. The availability of the INR/ISI scheme to monitor quality control of the laboratories in a reagent and method independent manner was examined by the comparison of 13 PT proficiency tests carried out by the ÖQUASTA (Austrian Society of Quality Assurance and Standardization of Diagnostic Medical Investigations).

In each proficiency test approximately 250 laboratories had to determine the PT of two to three lyophilized plasma samples with their routinely used reagents and methods. The INR mean values of the AK-plasmas (plasmapools from patients under anticoagulant therapy) were between 2 and 5. The determined data and the calculated INR-values were returned to the ÖQUASTA.

According to the INR/ISI scheme, all data should be considered as belonging to the same collective (TC = total collective). To prove this demand, additionally each reagent and method was evaluated separately (SC = single collective). It could be shown that the INR mean values obtained from all data and using TC or SC evaluation are nearly equivalent indicating that the TC evaluation is suitable for use in proficiency tests.

The aim of a better comparability of the PT values can not only be reached by the laboratories through the use of the INR/ISI scheme. Additionally, the manufacturer are asked to standardize their ISI and 100% value determination. The manufacturer took this into account by establishing a candidate reference plasma (5).

It could be shown that the introduction of the INR was not only an important step forward in terms of standardization and comparability of different thromboplastin reagents, but also in the quality control of the laboratories checked in proficiency tests in Austria.

Untersuchungen über clie Aktivierung von Serum-Proteasen durch Antigen-Antikörper-Reaktionen

Es wurde an Hand von Versuchen in vivo und in vitro gezeigt, daß Zusätze von Antigen zum Serum sensibilisierter Kaninchen zu einer Aktivierung der Serumprotease führen, wodurch verschiedene ältere Untersuchungen, insbeson dere aber die Befunde von Ungar zumindest teilweise bestätigt wurden. Für die erwähnte Antigenaktivierung der Serumprotease ist das Komplementsystem von ausschlaggebender Bedeutung; komplementfreies oder C’3-freies Serum läßt sich durch Antigenzusatz nicht aktivieren. Die Antigenaktivierung läßt sich durch Heparin aufheben.

Die mutmaßliche Bedeutung der Versuche als Modell für das anaphylaktische Geschehen wird diskutiert und an Hand von Versuchen mit dem Arthus-Phäno-men (lokalisierte anaphylaktische Reaktion) erläutert.

Assessment of cerebral oxygenation in neurocritical care patients: comparison of a new four wavelengths forehead regional saturation in oxygen sensor (EQUANOX®) with brain tissue oxygenation. A prospective observational study

BACKGROUND

Because of restricted information given by monitoring solely intracranial pressure and cerebral perfusion pressure, assessment of the cerebral oxygenation in neurocritical care patients would be of interest. The aim of this study was to determinate the correlation between the non-invasive measure regional saturation in oxygen (rSO2) with a third generation NIRS monitor and an invasive measure of brain tissue oxygenation tension (PbtO2).

METHODS

We conducted a prospective, observational, unblinded study including neurocritical care patients requiring a PbtO2 monitoring. Concomitant measurements of rSO2 were performed with a four wavelengths forehead sensor (EQUANOX Advance®) of the EQUANOX® 7600 System. We determined the correlation between rSO2 and PbtO2 and the ability of the rSO2 to detect ischemic episodes defined by a PbtO2 less than 15 mmHg. The rSO2 ischemic threshold was 60%.

RESULTS

During 2 months, 8 consecutives patients, including 275 measurements, were studied. There was no correlation between rSO2 and PbtO2 (r=0.016 [-0.103-0.134], r2=0.0003, P=0.8). On the 86 ischemic episodes detected by PbtO2, only 13 were also detected by rSO2. ROC curve showed the inability for rSO2 to detect cerebral hypoxia episodes (AUC=0.54).

CONCLUSION

rSO2 cannot be used as a substitute for PbtO2 to monitor cerebral oxygenation in neurocritical care patients.

Consumer exposure modelling under REACH: Assessing the defaults

Consumer exposure to chemicals from products and articles is rarely monitored. Since an assessment of consumer exposure has become particularly important under the European REACH Regulation, dedicated modelling approaches with exposure assessment tools are applied. The results of these tools are critically dependent on the default input values embedded in the tools. These inputs were therefore compiled for three lower tier tools (ECETOC TRA (version 3.0), EGRET and REACT)) and benchmarked against a higher tier tool (ConsExpo (version 4.1)). Mostly, conservative input values are used in the lower tier tools. Some cases were identified where the lower tier tools used less conservative values than ConsExpo. However, these deviations only rarely resulted in less conservative exposure estimates compared to ConsExpo, when tested in reference scenarios. This finding is mainly due to the conservatism of (a) the default value for the thickness of the product layer (with complete release of the substance) used for the prediction of dermal exposure and (b) the complete release assumed for volatile substances (i.e. substances with a vapour pressure ⩾10Pa) for inhalation exposure estimates. The examples demonstrate that care must be taken when changing critical defaults in order to retain conservative estimates of consumer exposure to chemicals.

[Thromboelastometric profile of unwashed shed blood after primary knee arthroplasty]

INTRODUCTION

Knee arthroplasty causes significant blood loss. Different blood-saving measures exist like retransfusion of unwashed salvaged blood. Some studies question the quality of this blood and in particular its ability to clot. These studies use "static" coagulation tests reflecting only partially the reality, unlike viscoelastic methods. The main objective of this study was to evaluate the salvaged blood thromboelastometric profile using ROTEM® system and to compare these results with patient venous blood.

MATERIALS AND METHODS

We performed an observational, prospective, single-center study conducted over 3 months in 2013. Agreement of local ethical committee and patient consent were obtained beforehand. All adult patients who underwent a primary total knee arthroplasty were included. A thromboelastometric profile and standard laboratory tests (hemoglobin, platelets count, PT, aPTT, fibrinogen) were performed in the same time on patient venous blood and on unwashed salvaged blood in the PACU.

RESULTS

Twenty patients were included. The median duration of surgery was 93 minutes. Thirteen patients (65%) received tranexamic acid during procedure. The median volume of shed blood was 225 mL. Two patients (10%) received a reinfusion. Analysis of shed blood showed a major deficiency of clotting factor in standard biology (PT<10%) and an absence of clot formation in thromboelastometric test (In-tem®, Ex-tem®, Fib-tem® or Ap-tem®). Compared to venous blood, shed blood had significantly lower hemoglobin levels: 8.8 vs 13.5 g/dL (P<0.0001). Allogenic transfusion concerned 5% of patients.

DISCUSSION

In this work, we confirmed that shed blood was naturally uncoagulable probably due to a multifactorial mechanism involving a major clot factor deficiency and an activation of fibrinolysis.

[Leg ischemia complicating the intraosseous infusion of epinephrine for a Djiboutian child]

Intraosseous infusion is increasingly used as an alternative to intravenous infusion. It is recommended for the cardiac arrest of a child in the first instance and after two failed attempts of intravenous infusion in the cardiac arrest of adults. Its rapid use and its low failure rate justify its use in all life-threatening emergencies. It can be used to administer the same treatments as intravenous infusion. It does, nonetheless, present some rare complications, such as acute leg ischemia by extravasation of epinephrine, as we report here. Awareness of these complications is necessary to ensure compliance with the rules of placing this type of infusion.

[Medication safety in the home care setting: error-prone process steps]

So far, little is known about drug-related problems in the homecare setting. It is estimated that up to 30% of homecare patients experience a potential medication error, most frequently happening during preparation and administration of drugs. In order to identify error-prone process steps in a Swiss homecare organisation caring for 1854 patients per year, direct observation of the medication use process, including the analysis of 10% of all prescriptions, was executed. Three complimentary methods were combined for the assessment of qualitative aspects of the medication use process: the analysis of a critical incident reporting system, a survey among homecare nurses, and a failure, mode and effects analysis. The medication use process is complex, consisting of 20 individual steps. Patients are prescribed an average of 7.5 ± 3.5 drugs per day, including 1 to 9 doses not suitable for deblistering into weekly dispensing systems. Of 84 reported errors, 74% happened during drug preparation. Communication with physicians, patients interrupting drug preparation and not transmitted changes of the drug regimen were considered the most critical process steps.

Aliskiren for the treatment of essential hypertension under real-life practice conditions: design and baseline data of the prospective 3A registry

BACKGROUND

The renin-angiotensin system (RAS) is a key target for blood pressure control and for cardiovascular and renal protection. Aliskiren is the first-in-class direct oral inhibitor of renin that controls the rate-limiting step in the RAS cascade. So far little is known about the use and efficacy of aliskiren in the treatment of essential hypertension under clinical practice conditions.

METHODS

The 3A registry was an open, prospective cohort study (observational registry) of 14,988 patients in 899 offices throughout Germany. Consecutive patients were eligible for inclusion if their physician had decided to modify their antihypertensive therapy. This included treatment with aliskiren or an angiotensin converting enzyme inhibitor (ACE-I)/angiotensin receptor blocker (ARB) or agents not blocking the RAS, alone or on top of an existing drug regimen.

RESULTS

Mean age of patients was 65 years, their mean body mass index was 28.2 kg/m(2) 53.5% were men, 36% working, 90% in statutory health insurance and 26% in any disease management programme. Patients in the aliskiren and the RAS groups compared with the non-RAS group were older, more often men, had a longer history of hypertension, and had a higher prevalence of comorbidities (diabetes, chronic heart failure, ischaemic heart disease, renal disease). Mean systolic, but not diastolic blood pressure was substantially higher in the aliskiren group (158/91 mmHg vs. 154/89 mmHg in ACE-I/ARB vs. 152/89 mmHg in non-RAS). Mean number of antihypertensive drugs was higher in the aliskiren group compared with the other groups (3.0 drugs vs. 2.5 in ACE-I/ARB vs. 1.6 in non-RAS; p < 0.0001).

CONCLUSIONS

In this large cohort of outpatients with hypertension, aliskiren was used mainly in patients with more severe stages of hypertension and those with concomitant diseases such as diabetes mellitus and impaired renal function. The 3A registry will provide important information about the use and efficacy of aliskiren in a real-life setting.

Age and diagnostic performance of Alzheimer disease CSF biomarkers

OBJECTIVES

Core CSF changes in Alzheimer disease (AD) are decreased amyloid β(1-42), increased total tau, and increased phospho-tau, probably indicating amyloid plaque accumulation, axonal degeneration, and tangle pathology, respectively. These biomarkers identify AD already at the predementia stage, but their diagnostic performance might be affected by age-dependent increase of AD-type brain pathology in cognitively unaffected elderly.

METHODS

We investigated effects of age on the diagnostic performance of CSF biomarkers in a uniquely large multicenter study population, including a cross-sectional cohort of 529 patients with AD dementia (median age 71, range 43-89 years) and 304 controls (67, 44-91 years), and a longitudinal cohort of 750 subjects without dementia with mild cognitive impairment (69, 43-89 years) followed for at least 2 years, or until dementia diagnosis.

RESULTS

The specificities for subjects without AD and the areas under the receiver operating characteristics curves decreased with age. However, the positive predictive value for a combination of biomarkers remained stable, while the negative predictive value decreased only slightly in old subjects, as an effect of the high AD prevalence in older ages.

CONCLUSION

Although the diagnostic accuracies for AD decreased with age, the predictive values for a combination of biomarkers remained essentially stable. The findings highlight biomarker variability across ages, but support the use of CSF biomarkers for AD even in older populations.

[Rare cause of heart failure in an elderly woman in Djibouti: left ventricular non compaction]

The purpose of this report is to describe the first case of left ventricular non compaction diagnosed in Djibouti. The patient was a 74-year-old Djiboutian woman with symptomatic heart failure. Echocardiography is the key tool for assessment of left ventricular non compaction. This rare cardiomyopathy is probably underdiagnosed in Africa.

[Upper airway management during anesthesia for reconstructive surgery in patients with noma]

Noma causes tissue degeneration of the face resulting in impaired mouth opening with secondary malnutrition and metabolic disorders. Reconstructive plastic surgery for noma can be lifesaving but requires special airway and ventilation techniques because of limited mouth opening. In addition, the African context imposes logistic and budgetary constraints. The purpose of this article is to describe an upper airway management strategy that takes into account disease factors and available resources.

Decompressive craniectomy guided by cerebral microdialysis and brain tissue oxygenation in a patient with meningitis

Bacterial meningitis remains a life-threatening disease mainly due to intracranial hypertension. However, decompressive craniectomy (DC) and the use of cerebral microdialysis (MD) and brain tissue oxygen pressure measurement (pTiO(2) ) are poorly described in this disease. We report a case of a 56-year-old woman admitted for severe bacterial meningitis complicating mastoiditis. Despite maximal medical treatment, intracranial pressure increased above 30 mmHg, with a decline in pTiO(2) and MD results indicating cerebral ischaemia. A bilateral DC was performed. Neurological outcome was favourable, and on discharge, the patient was able to live independently. This is the first report of DC in meningitis guided by cerebral MD and pTiO(2) . Invasive multimodal neuromonitoring should be used in severe meningitis and DC could be considered in the case of refractory intracranial hypertension.

Neutralizing CCL2 Inhibits Breast Tumor Growth Via Impact on the Tumor/Stroma Microenvironment

CCL2, (CC-chemokine ligand 2 or monocyte chemoattractant protein-1 (MCP-1)), is overexpressed in many human tumors and is believed to exert pro-tumor effects by recruiting monocytes to the tumor, where these cells become tumor associated macrophages (TAMs). TAMs secrete growth factors that stimulate angiogenesis and tumor growth, as well as proteases to promote tumor invasion and metastasis. CCL2 expression levels in primary breast tumors have been correlated with macrophage infiltration and blood vessel density, which in turn is correlated with disease stage and prognosis. These correlations indicate that CCL2 is a key player in tumor macrophage infiltration and/or tumor growth/invasion, and suggest that neutralizing CCL2 could be an effective form of therapy for breast cancer patients.The objective of these studies was to investigate whether CCL2 blockade could inhibit tumor growth in mice bearing human breast tumors. The human breast tumor cell lines MDA-MB-231 (ER-, PR-, Her2-) and MDA-MB-361 (ER+, PR+, Her2+) were implanted orthotopically in immunocompromised mice, and in both models the primary tumors metastasized to lungs and brain. Neutralizing antibodies to human CCL2 (CNTO 888) and to the mouse orthologs, MCP-1 and MCP-5, were administered therapeutically, either as a cocktail (termed CCL2 blockade) or individually to study the relative roles of host vs tumor derived CCL2 in promoting tumor growth.In both tumor models, CCL2 blockade significantly inhibited the growth of established primary tumors in the mammary fat pad. In addition, CCL2 blockade inhibited metastasis to distant sites. As measured by Taqman, visual inspection and immunohistochemistry, mice with MDA-MB-361 tumors treated with CCL2 blockade showed significantly reduced metastasis to lungs and brain, while mice bearing MDA-MB-231 tumors showed significantly reduced metastasis to lungs.To define the relative roles of human tumor-derived CCL2 vs mouse host-derived MCP-1/MCP-5, in vivo monotherapy tumor studies were conducted using the individual neutralizing antibodies. These studies included the mammary fat pad model and a tail vein metastasis model. In both cases, only the treatment with the anti-mouse MCP-1 antibody significantly inhibited primary tumor growth and distant metastasis, indistinguishable from the effect of CCL2 blockade treatment. In the tail vein metastasis model, the antibody treatment resulted in significantly fewer detectable lesions with these lesions showing a significant reduction in both tumor size and growth fraction, suggesting antibody treatment inhibits tumor seeding and growth. Mechanistic studies are in progress to further understand the basis of the anti-tumor effect mediated by the antibody treatment. These results demonstrate that host-derived MCP-1, produced from the tumor microenvironment, plays the critical role in tumor growth and metastasis in these models of human breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6095.

[One case report of tracheo-innominate artery fistula responsible of massive haemoptysis in a tracheotomized patient: which strategy to adopt?]

The tracheo-innominate artery fistula is a rare but life-threatening complication of the tracheotomy. Its care management requires a rapid airway control to allow haemostasis by compression and ventilation. The haemostasis must be immediate and two techniques exist: surgery opencast (sternotomy) or interventional radiology. The choice between the two depends largely on the technical platform available. Our case report describes a tracheo-innomninate artery fistula surgically managed with success. The patient carried an anatomic variant, the two carotids come from innominate artery.