Characterization of Polyethylene Branching by Thermal Analysis-Photoionization Mass Spectrometry

The rising demand for more and more specialized polyethylene represents a challenge for synthesis and analysis. The desired properties are dependent on the structure, but its elucidation is still intricate. For this purpose, we applied thermal analysis hyphenated to single photon ionization mass spectrometry (STA-SPI-MS). The melting and pyrolysis behavior of different types of polyethylene were tracked by DSC and mass loss. Crystallinity and melting point give hints about the branching but are also influenced by the molecular weight distribution. The evolving gas analysis patterns obtained by SPI-MS however, contain specific molecular information about the samples. Shifts in the summed spectra, which can be clearly observed with our technique, result from differently favored degradation reactions due to the respective structure. Pyrolysis gas chromatography mass spectrometry (Py-GC-EI-MS) was used to support the assignment of pyrolysis products. Principal component analysis was successfully applied to reduce the complexity of data and find suitable markers. The obtained grouping is based on the molecular fingerprint of the samples and is strongly influenced by short-chain branching. Short and medium alkenes and dienes have the strongest impact on the first four principal components. Thus, two marker ratios could be defined, which also give a comprehensible and robust grouping. Butene and pentene were the most abundant signals in our set of samples. With STA-PI-MS, a broad range of pyrolysis products can be measured at the same time, possibly extending the range for quantifiable short-chain branches to more than six carbon atoms for PE. Unfortunately, no clear trend between long-chain branching and any grouping was observed. The quite universal and soft single photon ionization enables access to many different compound classes and hence other polymers can be studied.

Membrane phospholipid composition of Pseudomonas aeruginosa grown in a cystic fibrosis mucus-mimicking medium

BACKGROUND

Pseudomonas aeruginosa is a bacterium able to induce serious pulmonary infections in cystic fibrosis (CF) patients. This bacterium is very often antibiotic resistant, partly because of its membrane impermeability, which is linked to the membrane lipid composition. This work aims to study the membrane phospholipids of P. aeruginosa grown in CF sputum-like media.

METHODS

Three media were used: Mueller Hilton broth (MHB), synthetic cystic fibrosis medium (SCFM) and 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) complemented SCFM (SCFM-PC). Lipids were extracted and LC-MS/MS analyses were performed. Growth curves, atomic force microscopy images and minimal inhibitory concentration determination were performed in order to compare the growth and potentially link lipid modifications to antibiotic resistance.

RESULTS

Semi-quantification showed phospholipid quantity variation depending on the growth medium. Phosphatidylcholines were detected in traces in SCFM. MS/MS experiments showed an increase of phospholipids derived from DOPC in SCFM-PC. We observed no influence of the medium on the bacterial growth and a minor influence on the bacterial shape. MIC values were generally higher in SCFM and SCFM-PC than in MHB.

CONCLUSIONS

We defined a CF sputum-like media which can be used for the membrane lipid extraction of P. aeruginosa. We also showed that the growth medium does have an influence on its membrane lipid composition and antibiotic resistance, especially for SCFM-PC in which P. aeruginosa uses DOPC, in order to make its own membrane.

GENERAL SIGNIFICANCE

Our results show that considerable caution must be taken when choosing a medium for lipid identification and antibiotic testing -especially for phospholipids-enriched media.

Mediterranean diet, sociodemographic factors and ultra-processed food consumption in Portugal

Background

Mediterranean diet has been shown to promote beneficial effects on health, while ultra-processed food (UPF) consumption has been associated with lower diet quality and higher risk for non-communicable diseases. Our aims were to explore the adherence to a Mediterranean dietary pattern (MDP) in Portugal and its association with sociodemographic factors and UPF consumption.

Methods

Participants were from the Portuguese National Food, Nutrition and Physical Activity Survey 2015-2016, aged 18-84y (n = 3,852). CAPI face-to-face interviews were used including 2 dietary 24-h recalls. UPF were identified using NOVA classification. Adherence to MDP was defined by the Mediterranean Diet Score (MDS), which may vary from 0 to 9. MDS≥6 was considered as high adherence. Weighted multivariate logistic regression analysis was used to explore associations of high adherence to MDP with sex, age, region, educational level, family income and dietary share of UPF groups.

Results

High adherence to MDP was observed for 19.6% of participants and was inversely associated with higher consumption of UPF, namely, sugar-sweetened beverages (OR = 0.924; 95%CI 0.883-0.966), confectionery (OR = 0.893; 95%CI 0.816-0.977), sweet snacks (OR = 0.953; 95%CI 0.923-0.985), cakes/desserts (OR = 0.956; 95%CI 0.934-0.978) and meat products (OR = 0.922; 95%CI 0.874-0.972). Being female (OR = 0.629; 95%CI 0.471-0.841) and not from the North or Alentejo regions were inversely associated with high adherence to MDP. There was no relation between income and adherence to MDP. The higher the level of education or age, the higher the odds of high adherence to MDP (OR = 2.573; 95%CI 1.741-3.803 and OR = 1.028; 95%CI 1.020-1.037, respectively).

Conclusions

Actions to improve adherence to MDP in Portugal should consider discouraging UPF consumption and be addressed to specific subgroups.

Funding

POCI-01-0145-FEDER-032090 (FCT/FEDER); FAPESP 2018/07391-9, 2019/05972-7 (MCR), 2016/14302-7 (FR).

Key messages

High adherence to a Mediterranean dietary pattern was observed for near 20% of Potuguese over 18 years old. The higher the level of education or age, the higher the odds of high adherence to MDP. High adherence to a Mediterranean dietary pattern was inversely associated with higher consumption of sugar-sweetened beverages, confectionery, sweet snacks, cakes/desserts and meat products.

Availability of ultra-processed food associated with health outcomes: a systematic review

Background

Ultra-processed food (UPF) consumption increases worldwide, which can be harm to population's health. To establish associations between UPF and health outcomes, food consumption can be assessed individually or by using availability data, such as purchase lists or household budget surveys. The aim of this review was to search for studies on the availability of UPF related with mortality and morbidity from noncommunicable diseases or their risk factors.

Methods

PRISMA guideline was used. Searches were performed on PubMED, EBSCO, Scopus and Web of Science on December 2019. Search strategy included terms related with exposure (UPF) and outcomes (mortality or morbidity from noncommunicable diseases and their risk factors). Studies were selected based on the title and abstracts. Full texts were screened for eligibility and the snowballing method was used to find other relevant studies. To be based on UPF availability data and its relation with health outcomes were the inclusion criteria. Studies that assessed only food consumption at an individual level and did not present health outcome were excluded. Selection was conducted by two reviewers and a third helped when disagreement occurred.

Results

After duplicates removal, 560 records were analyzed. From the 11 eligible studies, 55% were conducted in more than one country. Others were performed in Brazil (27%), Guatemala (9%) and Sweden (9%). Studies were ecological (64%), cross-sectional (27%) and longitudinal (9%). All had representative samples, 45.5% were national samples, and the others were from particular population subgroups. In all studies, the only health outcomes that showed positive association with UPF availability were overweight and obesity prevalence.

Conclusions

Studies relating ultra-processed food availability and health outcomes are mainly focused on overweight and obesity. It is thus necessary to further explore the relationship between UPF availability and other health outcomes.

Key messages

It is necessary to further research association between ultra-processed food availability and other health outcomes, such as morbidity and mortality from cardiovascular diseases, diabetes or cancer. Purchase lists or household budget surveys are an important source of food availability data and can be used to relate the consumption of ultra-processed foods to health outcomes.

Children-menus in restaurants of Portuguese, Hungarian and Croatian shopping centres: A qualitative study

Background

Families to eat out frequently use shopping centres and, there is evidence that children's menus are poor nutritional quality. Obesity rates have increased all over the world, and it has been associated to the observed out of home food consumption. This study aimed to characterise children's menus in shopping center restaurants in Portugal, Hungary and Croatia, as a preliminary study to further develop strategies to intervene.

Methods

An observational cross-sectional study was carried out in shopping centres in Portugal, Hungary and Croatia. Only the ones providing a children's menu were selected. Data collection tool was developed by the research team, consisting of a three-section form to identify and characterise the restaurant and analyses the quality of children's menu.

Results

Researcher visited 295 restaurants, from which only 69 provided a children's menu. From these 12 restaurants offered gifts associated with it. The most frequently featured items on the menu were hamburgers (22%), grilled or fried chicken (19%), nuggets (17%) and pizza (12%). Potato chips were the most frequent side dish option (33%). Only 11 restaurants offered vegetable soup or vegetables. Although water was available, a variety of soft drinks and sugary fruit juices were also options. Sweet dessert is a common part of the menu. Nutritional information is present in only 13% of the menus. Menu prices do not differ much, Portugal having the higher average (x ̅ = €5.35±1.45). Hungary had the lower average (x ̅ = €4.30±1.50) and Croatia the lowest range (min=€3.00, max=€7.40).

Conclusions

Children's menu options have poor quality. Shifting foods offered to children in restaurants has the potential to improve diet quality, reduce excess energy intake and promote healthy eating habits.

Key messages

European strategies are needed to promote children healthy food environment. Following aim is to develop and test balanced menus for children among food chains.

High-performance thin-layer chromatography with atmospheric solids analysis probe mass spectrometry for analysis of gasoline polymeric additives

RATIONALE

The offline coupling of high-performance thin-layer chromatography (HPTLC) with atmospheric solids analysis probe mass spectrometry (ASAP-MS) was evaluated for the characterization of polymeric additives in gasoline.

METHODS

A protocol was developed to optimize the ion signal. A glass capillary was moistened with deionized water, and then dipped into silica gel scratched from an HPTLC plate. The capillary tube was fixed to the ASAP holder and introduced into the ionization source for analysis by MS. Silica gel, reversed-phase C18 and cellulose stationary phases were evaluated.

RESULTS

The effect of the stationary phase and the nature of analyte were evaluated using polypropylene glycol and polyisobutylene succinimide polyamine as analyte molecules. The optimal ionization conditions are significantly different between ASAP and HPTLC/ASAP-MS analyses. In particular, a higher desorption gas temperature was required to produce ions from the silica gel HPTLC plate. The presence of the stationary phase reduces the internal energy of the ions and limits the fragmentation.

CONCLUSIONS

HPTLC/ASAP-MS is a very fast and efficient technique for the analysis of polymers in formulated fuels. Good ionization efficiency was obtained with all investigated stationary phases.

FRI0388 ARE WE OVERLOOKING OSTEOARTHRITIS? – A COMPARATIVE STUDY OF PAIN, FUNCTION AND QUALIFY OF LIFE IN PATIENTS WITH HAND OSTEOARTHRITIS AND RHEUMATOID ARTHRITIS

Background:

Osteoarthritis (OA) is frequently regarded by patients and health care providers as a normal consequence of ageing (1). On the other hand, it is well established that rheumatoid arthritis (RA) is a pathological condition requiring prompt and efficacious treatment and in which remarkable progresses have been achieved in the last decades. Pain and physical limitations are hallmarks of both conditions. Some previous studies suggest that OA and RA may have a similar burden (2,3).

Objectives:

To compare levels of pain, physical disability and health-related quality of life in patients with primary hand osteoarthritis (hOA) and with RA: active disease (aRA) or in remission (rRA).

Methods:

Observational cross-sectional study including patients of two clinical centres with hOA and RA, either in remission or with active disease (at least two swollen and/or tender hand joints). Matching for sex and age was performed. Patients were asked to complete a survey consisting of visual analogic scale (VAS) for pain, Health Assessment Questionnaire (HAQ) and Short Form 36 (SF36). Mean values for each domain were compared between the three groups using one-way ANOVA test with significance accepted for p<.05.

Results:

Thirty patients with hOA and 93 with RA (33 with aRA and 60 with rRA) were included. All patients were caucasian females with no significant differences in age between groups. Patients with hOA reported higher levels of pain in comparison with aRA patients (mean VAS 57.3vs49.3mm, respectively, p=.265) and with rRA patients (57.3vs28.6mm, respectively, p<.001) [F(2.120)=25.907, p<.001]. Regarding physical function, patients with hOA reported levels of disability similar to rRA patients, but significantly lower disability than patients with aRA [F(2.120)=6.962, p=.001]. Patients with hOA evaluated their quality of life significantly better than patients with aRA and in similar levels to patients with rRA, as measured by mental health and general health status domains of SF36.

Conclusion:

Our results show that hOA may have similar or even higher burden of pain than RA; this is in line with previous studies, although most of them did not consider the level of inflammatory activity of RA. On the other hand, patients with hOA seem to preserve function and have better health-related quality of life despite the higher levels of pain. These results highlight OA as a cause of severe pain, which should lead us to try an optimal symptom control for these patients. These findings should also encourage rheumatologists to endeavor efforts to perform more studies in the field of OA, to better understand its pathogenesis and to eventually find disease modifying drugs.

References:

[1]Gignac MAM, Davis AM, Hawker G, Wright JG, Mahomed N, Fortin PR, et al. “What do you expect? You’re just getting older”: A comparison of perceived osteoarthritis-related and aging-related health experiences in middle- and older-age adults. Arthritis Rheum. 2006 Dec 15;55(6):905–12.

[2]El-Haddad C, Castrejon I, Gibson KA, Yazici Y, Bergman MJ, Pincus T. MDHAQ/RAPID3 scores in patients with osteoarthritis are similar to or higher than in patients with rheumatoid arthritis: a cross-sectional study from current routine rheumatology care at four sites. RMD Open. 2017 Jul;3(1):e000391.

[3]Slatkowsky-Christensen B, Mowinckel P, Kvien T. Health status and perception of pain: a comparative study between female patients with hand osteoarthritis and rheumatoid arthritis. Scand J Rheumatol. 2009 Jan;38(5):342–8.

Disclosure of Interests:

None declared

AB0192 RHEUMATOID ARTHRITIS: IS IT WORTH IT TO ADD LEFLUNOMIDE TO METHOTREXATE IN REFRACTORY DISEASE?

Background:

In refractory rheumatoid arthritis (RA), adding other classic synthetic disease-modifying antirheumatic drug (csDMARD) such as leflunomide (LFN) to methotrexate (MTX) is one suitable option [1,2]. Yet, there are safety issues to consider which may limit this strategy, but also regarding its true effectiveness in avoiding exposure to biological DMARDs (bDMARD) or target synthetic DMARDs (tsDMARD).

Objectives:

To assess the effectiveness and safety of adding LFN to MTX and to evaluate the predictors of drug retention, toxicity and inefficacy.

Methods:

A retrospective clinical record review of adult RA patients followed on our rheumatology department in whom LFN was added to MTX was done. Sociodemographic information, comorbidities, disease related information, adverse reactions and disease activity according to Disease Activity Score 28 – C reactive protein (DAS28) were recorded at baseline and after 3, 6 and 12 months of combination therapy (3_DAS28; 6_DAS28; 12_DAS28, respectively). Information regarding toxicity (need to dose adjustment/suspension) and inefficacy (add/switch to bDMARD/tsDMARD) were recorded. Follow-up was considered until last medical record available. SPSS was used for statistical analysis. Kaplan Meier and Cox-regression were used for univariate and multivariate analysis, respectively, significant level was 2-sidedp<.05.

Results:

In total, 77 patients were included, 66.20% females, with a mean age of 56±11 years old. There was a significant reduction of DAS28 only after 3 months of therapy (4.01±1.01 to 2.57±1.52,p=.003; ΔDAS28 = 1.58±1.17). However, during a median follow up time of 64 (IQR 39-83) months, 58.44% of patients needed to change treatment strategy, 66.67% due to toxicity (median time to toxicity 13 months, IQR 2-16) and 33.33% due to inefficacy (median time to inefficacy of 10 months, IQR 5.84-17.64). Gastrointestinal intolerance was the main reported toxicity (46.15%). In univariate analysis, anti-citrullinated protein antibodies (ACPA) positivity, alcohol consumption, lack of comorbidities, hepatic toxicity, higher 6_DAS28, swollen joint count and tender joint count on the 6thmonth were associated to lower retention rates.

In multivariate analysis, lack of comorbidities (HR=3.3, CI 95% 1.4-7.8,p=.006) and higher 6_DAS28 (HR=0.32, CI 95% 0.14-0.72,p=.006) were independent predictors of suspension of combination therapy. Moreover, both male gender (HR=2.87, 95%CI 1.2-6.56,p=.016) and positivity to ACPA (HR=0.1, 95%CI 0.01-0.73,p=.024) were independent predictors of toxicity. There was also higher tendency to toxicity, but without statistical significance, in alcohol consumers (p=.08). Regarding inefficacy, smoking habits (HR=0.15, 95%CI 0.04-0.52) and 3_DAS28 (HR=0.15, 95%CI 0.04-0.53) were independent predictors.

Conclusion:

Addition of LFN to MTX showed an early positive response. However, it was frequently associated to toxicity, and less than half of the patients continued with this therapeutic strategy after 5 years of follow up. Male gender, smoking habits and positivity to ACPA were predictors of worse outcome, as already reported in literature [1]. Lack of comorbidities was an independent predictor of suspension. This can be explained by the fact that physicians tend to adopt a more aggressive strategy on patients without comorbidities, switching earlier to bDMARDs/tsDMARDs.

This study also showed that early response to combination therapy is an independent predictor on drug retention, suggesting that decisions on treatment strategy should be made early after the beginning of MTX/LFN.

References:

[1]Smolen JS, et al. Ann Rheum Dis 2020;0:1–15. doi:10.1136/annrheumdis-2019-216655

[2]Kremer J, et al. J Rheumatol. 2004 Aug;31(8):1521-31. PMID: 15290730

Disclosure of Interests:

None declared

AB0236 DIFFERENCES AND DETERMINANTS OF PHYSICIAN’S AND PATIENT’S PERCEPTION IN GLOBAL ASSESSMENT OF RHEUMATOID ARTHRITIS

Background:

Patient’s Global Assessment of Disease Activity (PtGA) and Physician’s Global Assessment of Disease Activity (PhGA) are assessed as part of commonly used measures of disease activity in RA.1Both are important measures in treat-to-target strategies in Rheumatoid Arthritis (RA), but often provide discordant results.2,3This can provide an erroneous assessment of disease activity in patients under Biologic treatment and mislead treatment decisions, namely switches.

Objectives:

To assess differences and determinants of PtGA and PhGA in RA patients under biologic treatment.

Methods:

Cross-sectional study, including 46 patients with RA diagnosed according to the ACR/EULAR criteria, under biologic treatment, consecutively evaluated in day-care unit. Participants completed patient-reported outcomes (PROs), including PtGA, and sociodemographic characteristics. Physicians collected comorbidities and parameters of inflammatory activity (erythrocyte sedimentation rate [ESR] and C-reactive protein [CRP]) and completed PhGA and disease activity score 28 with ESR (DAS28). SPSS was used for statistical analysis and significance level was defined as 2-sided p<0.05.

Results:

Clinical and laboratory characteristics of patients are shown in table 1. PtGA and PhGA were significantly different (36.1±27.6 mmvs8.7±14.2 mm, p< 0.001) and a positive discordance (PtGA>PhGA, more than 25mm in visual analogue scale [VAS]) was found in 54.3% of cases.

PtGA had a correlation with PROs (Pain VAS, 36-Item Short Form Health Survey [SF-36], Health Assessment Questionnaire [HAQ], Functional Assessment of Chronic Illness Therapy [FACIT], EuroQol [EQ5D] and Hospital Anxiety and Depression Scale [HADS]), CRP, tender and swollen joint counts and an association with comorbidities like fibromyalgia or osteoarthritis (OA). No association was found between PtGA and age, sex, education level, profession, employment status, extra-articular manifestations, positivity of rheumatoid factor, ESR, years of disease evolution or number of biologic treatments. In multivariable analyse including SF-36, CRP, tender joints count and OA (R2adjusted= 0.672), the main predictors of PtGA were lower SF36, concomitant OA and higher CRP level.

PhGA had a correlation with PtGA, pain VAS, CRP, tender and swollen joints. No association was found between PhGA and patient or physician age, patient or physician sex, extra-articular manifestations, positivity of rheumatoid factor, ESR level, years of disease evolution or number of biologic treatments. In multivariable analysis including ESR, tender and swollen joints count and CRP (R2adjusted= .800), the main predictors of PhGA were swollen joint count and higher CRP level.

Conclusion:

This study showed the variability implied on global assessment of RA activity. Overall PtGA is based on function and also in subjective and emotional experience of pain, whereas the PhGA is based on more objective measures, more related to disease activity.

References:

[1]Kanekoa Y. et al, Determinants of Patient’s Global Assessment of Disease Activity and Physician’s Global Assessment of Disease Activity in patients with rheumatoid arthritis: A post hoc analysis of overall and Japanese results from phase 3 clinical trials.Modern Rheumatology2018; 28(6):960–967

[2]Furu M. et al. Discordance and accordance between patient’s and physician’s assessments in rheumatoid arthritis.Scand J Rheumatol.2014; 43(4):291-5.

Ann Rheum Dis. 2016 Sep;75(9):1661-6. doi: 10.1136/annrheumdis-2015-208251. Epub 2015 Oct 22.

[3]Portier A. et al, Patient-perceived flares in rheumatoid arthritis: A sub-analysis of the STRASS treatment tapering strategy trial.Joint Bone Spine. 2017; 84(5):577-581

Disclosure of Interests:

None declared

AB1350-HPR SOCIOECONOMIC BURDEN OF NON-ATTENDANCE IN RHEUMATOLOGY CONSULTATION

Background:

Outpatient non-attendance refers to the phenomenon of patients who have a medical appointment but do not show up at the specified date, time, and location without giving previous notice.1In addition to affecting the efficiency and thereby increasing the healthcare total costs, nonattendance might also delay access to care for users on waiting lists.1Nonattendance at health appointments is costly to services, and can risk patient health.2There is very little data on the nonattendance prevalence and impact in Portugal. This knowledge might be fundamental to improve effectiveness of outpatient care in Portugal.

Objectives:

1) describe patient’s non-attendance rate; 2) assess and characterize the sociodemographic and clinical characteristics among non-attending patients; 3) estimate the economic burden of non-attendance.

Methods:

Retrospective, cross-sectional and analytical study. We reviewed a one-month Rheumatology consultation period regarding performed medical consultations and non-attended consultations without previous notification from patients. Direct economic costs of non-attended appointments were calculated based on the “Amending Agreement to the ULSAM, EPE Program Agreement”.

Results:

982 consultations within January 2018 were included. Appointments episodes for therapeutic prescription, medical reports or programmed admissions were excluded. Fifty-seven (5.8%) of scheduled outpatient appointments were non-attended. Subsequent consultations represented 85.2% of attended appointments and 80.7% of non-attended appointments. Female gender was the most prevalent in both groups – 620 (67.0%) among attended consultations and 37 (65.0%) among non-attended consultations. Mean age was 57±15 years in the first group and 54±16 years in the second one. Among attended appointments, mean education level was 8±5 years versus 9±6 years among non-attended appointments. There were no differences between both groups in gender, age, education level, diagnosis, disease duration and activity or appointment type (first or subsequent consultation). A cost of 2,438 euros was estimated regarding non-attended appointments for this period, what could represent a burden of more than 29,000 euros yearly, in direct costs, only.

Conclusion:

Non-attendance at scheduled appointments in public hospitals seems to be influenced by other factors besides gender, age and education level. The burden of non-attended appointments is undeniable. In addition to the costs estimated in this study, further indirect costs such as poorer patients outcomes, impaired access to medical care and hospital penalties should be taken into account. Implementation of awareness strategies aiming the optimization and effectiveness of healthcare system are required.

References:

[1]Blæhr EE, Kristensen T, Væggemose U, Søgaard R. The effect of fines on nonattendance in public hospital outpatient clinics: study protocol for a randomized controlled trial.Trials. 2016;17(1):288. doi:10.1186/s13063-016-1420-3

[2]Akter S. A qualitative study of staff perspectives of patient non-attendance in a regional primary healthcare setting.Australas Med J. 2014;7(5):218-226. doi:10.4066/AMJ.2014.2056

Disclosure of Interests:

None declared

High-resolution mass spectrometry for future space missions: Comparative analysis of complex organic matter with LAb-CosmOrbitrap and laser desorption/ionization Fourier transform ion cyclotron resonance

RATIONALE

Mass spectrometers are regularly boarded on spacecraft for the exploration of the Solar System. A better understanding of the origin, distribution and evolution of organic matter and its relationships with inorganic matter in different extra-terrestrial environments requires the development of innovative space tools, described as Ultra-High-Resolution Mass Spectrometry (UHRMS) instruments.

METHODS

Analyses of a complex organic material simulating extraterrestrial matter (Titan's tholins) are performed with a homemade space-designed Orbitrap™ equipped with a laser ablation ionization source at 266 nm: the LAb-CosmOrbitrap. Mass spectra are obtained using only one laser shot and transient duration of 838 ms. A comparison is made on the same sample with a laboratory benchmark mass spectrometer: a Fourier Transform Ion Cyclotron Resonance equipped with a laser desorption ionization source at 355 nm (LDI-FTICR) allowing accumulation of 20,000 laser shots.

RESULTS

Mass spectra and attributions of molecular formulae based on the peaks detected by both techniques show significant similarities. Detection and identification of the same species are validated. The formation of clusters ions with the LAb-CosmOrbitrap is also presented. This specific feature brings informative and unusual indirect detections about the chemical compounds constituting Titan's tholins. In particular, the detection of HCN confirms previous results obtained with laboratory Electrospray Ionization (ESI)-UHRMS studies about the understanding of polymeric patterns for the formation of tholins.

CONCLUSIONS

The capabilities of the LAb-CosmOrbitrap to decipher complex organic mixtures using single laser shot and a short transient are highlighted. In agreement with results provided by a commercial FTICR instrument in the laboratory, we demonstrate in this work the relevance of a space laser-CosmOrbitrap instrument for future planetary exploration.

Particulate inorganic salts and trace element emissions of a domestic boiler fed with five commercial brands of wood pellets

Pellet stoves arouse a real interest from consumers because they are perceived as a renewable and carbon neutral energy. However, wood combustion can contribute significantly to air pollution, in particular through the emission of particulate matter (PM). In this article, five brands of wood pellets were burnt under optimal combustion conditions and trace element and inorganic salt emission factors (EFs) in PM were determined. Results show that a significant proportion of metals such as lead, zinc, cadmium, and copper initially present in pellets were emitted into the air during combustion with 20 ± 6%, 31 ± 12%, and 19 ± 6% of the initial content respectively for Zn, Pb, and Cd. The median emission factors for Pb, Cu, Cd, As, Zn, and Ni were respectively 188, 86, 9.3, 8.7, 2177, and 3.5 μg kg^-1. The inorganic fraction of the PM emissions was dominated by K⁺, SO₄^2-, and Cl^- with respective EFs of 33, 28.7, and 11.2 mg kg^-1. Even taking into account a consumption of 40.1 million tons by 2030 in the EU, the resulting pollution in terms of heavy metal emissions remains minimal in comparison with global emissions in the EU.

Optimization of ion trajectories in a dynamically harmonized Fourier-transform ion cyclotron resonance cell using a design of experiments strategy

RATIONALE

With the recent introduction of the dynamically harmonized Fourier-transform ion cyclotron resonance (FT-ICR) cell, the complexity of tuning has expanded drastically, and fine-tuning of the direct current voltages is required to optimize the ion cloud movement. As this adjustment must typically be performed manually, more reliable computational methods would be useful.

METHODS

Here we propose a computational method based on a design of experiments (DoE) strategy to overcome the limits of classical manual tuning. This DoE strategy was exemplarily applied on a 12 T FT-ICR instrument equipped with a dynamically harmonized ICR cell. The chemometric approach, based on a central composite face (CCF) design, was first applied to a reference material (sodium trifluoroacetate) allowing for the evaluation of the primary cell parameters. Eight factors related to shimming and gating were identified. The summed intensity of the signal corresponding to the even harmonics was defined as one quality criterion.

RESULTS

The DoE response allowed for rapid and complete mapping of cell parameters resulting in an optimized parameter set. The new set of cell parameters was applied to the study of an ultra-complex sample: Tholins, an ultra-complex mixture that mimics the haze present on Titan, was chosen. We observed a substantial improvement in mass spectrometric performance. The sum of signals related to harmonics was decreased by a factor of three (from 4% for conventional tuning to 1.3%). Furthermore, the dynamic range was also increased, which in turn led to an increase in attributed peaks by 13%.

CONCLUSIONS

This computational procedure based on an experimental design can be applied to any other mass spectrometric parameter optimization problem. This strategy will lead to a more transparent and data-driven method development.

Collision Cross Sections of Phosphoric Acid Cluster Anions in Helium Measured by Drift Tube Ion Mobility Mass Spectrometry

In the last years, ion mobility mass spectrometry (IMS-MS) has improved structural analysis and compound identification by giving access to the collision cross section (CCS). An increasingly wide and accurate database of CCS values is now available but often without assessment of the influence of different instrumental settings on CCS values. Here, we present 75 CCS values in helium (^DTCCS_He) for phosphoric acid cluster anions [(H₃PO₄)_n - zH]^z- with charge state (z) up to 4-. The CCS values, noted ^DTCCS_He, were obtained with a commercial drift tube ion mobility mass spectrometer, in helium, by applying a classic multifield approach. Phosphoric acid clusters are fragile structures that allow to evaluate the effect of different experimental conditions on the retention of weak bonds and their effect on CCS values. We probed harsh and soft voltage gradients in the electrospray (ESI) source before the IMS and two different voltage gradients in the post-IMS region. The variations in the ion mobility and mass spectra consisted in a change in the distribution of the cluster anions aggregation numbers (n) and charge states (z), with a higher amount of multiply charged species for the soft pre-IMS voltage gradient and a lower proportion of cluster dissociation for soft post-IMS conditions. However, the CCS values did not change with experimental conditions for a given cluster, as long as it stays intact from the IMS to the mass analyzer. The ^DTCCS_He were found in good agreement among 3 to 10 replicated values, with a relative standard deviation between 0.1 and 1.7%.

Direct Inlet Probe Atmospheric Pressure Photo and Chemical Ionization Coupled to Ultrahigh Resolution Mass Spectrometry for the Description of Lignocellulosic Biomass

Lignocellulosic biomass, in particular wood, is a complex mixture containing cellulose, hemicellulose, lignin, and other trace compounds. Chemical analysis of these biomasses, especially lignin components, is a challenge. Lignin is a highly reticulated polymer that is poorly soluble and usually requires chemical, enzymatic, or thermal degradation for its analysis. Here, we studied the thermal degradation of lignocellulosic biomass using a direct insertion probe (DIP). The DIP was used with two ionization sources: atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI) coupled to ultrahigh-resolution mass spectrometry. Beech lignocellulosic biomass samples were used to develop the DIP-APCI/APPI methodology. Two other wood species (maple and oak) were analyzed after optimization of DIP parameters. The two ionization sources were compared at first and showed different responses toward beech samples, according to the source specificity. APPI was more specific to lignin degradation compounds, whereas APCI covered a larger variety of oxygenated compounds, e.g., fatty acids and polyphenolics compounds, in addition to lignin degradation products. The study of the thermodesorption profile gave information on the different steps of lignocellulosic biomass pyrolysis. The comparison of the three feed sample types (oak, maple, and beech), using principal component analysis (PCA) with DIP-APCI experiments, showed molecular level differences between beech wood pellets and the two other wood species (maple and oak).

Multiple xylosyltransferases heterogeneously xylosylate protein N-linked glycans in Chlamydomonas reinhardtii

Nowadays, little information is available regarding the N-glycosylation pathway in the green microalga Chlamydomonas reinhardtii. Recent investigation demonstrated that C. reinhardtii synthesizes linear oligomannosides. Maturation of these oligomannosides results in N-glycans that are partially methylated and carry one or two xylose residues. One xylose residue was demonstrated to be a core β(1,2)-xylose. Recently, N-glycoproteomic analysis performed on glycoproteins secreted by C. reinhardtii demonstrated that the xylosyltransferase A (XTA) was responsible for the addition of the core β(1,2)-xylose. Furthermore, another xylosyltransferase candidate named XTB was suggested to be involved in the xylosylation in C. reinhardtii. In the present study, we focus especially on the characterization of the structures of the xylosylated N-glycans from C. reinhardtii taking advantage of insertional mutants of XTA and XTB, and of the XTA/XTB double-mutant. The combination of mass spectrometry approaches allowed us to identify the major N-glycan structures bearing one or two xylose residues. They confirm that XTA is responsible for the addition of the core β(1,2)-xylose, whereas XTB is involved in the addition of the xylose residue onto the linear branch of the N-glycan as well as in the partial addition of the core β(1,2)-xylose suggesting that this transferase exhibits a low substrate specificity. Analysis of the double-mutant suggests that an additional xylosyltransferase is involved in the xylosylation process in C. reinhardtii. Additional putative candidates have been identified in the C. reinhardtii genome. Altogether, these results pave the way for a better understanding of the C. reinhardtii N-glycosylation pathway.

Paraffin-Inert Atmospheric Solid Analysis Probe: A Fast and Easy Approach To Characterize Extremely Air-Sensitive Organometallic Complexes by Mass Spectrometry

Rational characterization of most organometallic compounds is hampered by their high reactivity, in particular, toward oxygen and water. Mass spectrometry experiments require physical introduction of the sample in the ionization source. So, the main challenge is to transfer air-sensitive organometallic compounds from inert atmosphere to the ionization source. In this aim, we have developed an easy technique that allows the analysis of air-sensitive compounds using the atmospheric solid analysis probe (ASAP). This method consists of a glass capillary filled with the sample (solid or liquid) and sealed by a paraffin plug to maintain the inert sample until the ionization process. It is illustrated through the structural characterization of a new highly air-sensitive dinuclear zirconium complex supported by an original switchable stilbene platform.

Adherence to a Mediterranean Dietary Pattern and Functional Parameters: A Cross-Sectional Study in an Older Population

OBJECTIVES

In older adults, diet and physical activity are among the most important behaviours that influence health. The Mediterranean Dietary Pattern has been related to longevity and can benefit physical function in older adults. The present study aims to quantify the association of adherence to a Mediterranean Dietary Pattern with physical functioning through by handgrip strength, as well as, with sedentary behaviour based on sitting time, in a sample of older adults.

METHODS

A cross-sectional study was conducted in 1,491 older adults ≥ 65 years old. The adherence or non-adherence to a Mediterranean Dietary Pattern was assessed using the previously validated and translated 14 item questionnaire, the PREDIMED (Prevención com Dieta Mediterránea). Handgrip strength was measured with a Jamar Dynamometer. Sitting time per day was used as an indicator of sedentary behaviour. Multinomial logistic regressions were performed to quantify the association of adherence to a Mediterranean Dietary Pattern with handgrip strength and sitting time.

RESULTS

Compared to participants who adhered to a Mediterranean Dietary Pattern, those who did not adhere to this diet have a significantly higher adjusted odds ratio for low handgrip strength [adjusted odds ratio: 1.50; 95% confidence interval: 1.09-2.05], as well as for longer sitting time [adjusted odds ratio: 1.43; 95% confidence interval: 1.04-1.96].

CONCLUSION

In older adults, the non-adherence to a Mediterranean Dietary Pattern was associated with both lower values of handgrip strength and longer sitting time.

Bioprospection of Isochrysis galbana and its potential as a nutraceutical

Microalgae have strong potential as novel sources of nutraceuticals, as they contain significant amounts of highly valuable bioactive compounds. This study focuses on the bioprospection of biomass of the microalga Isochrysis galbana and its extracts (aqueous and ethanolic), determining total polyphenols, laminarin, fucoxanthin, coenzyme Q10, and β-carotene contents, and also assessing several biological activities (antioxidant, cytotoxicity, and hypocholesterolemic). I. galbana exhibited high phenolic content, both in aqueous and ethanolic extracts. The microalgal freeze-dried biomass presented a low laminarin content and higher content of fucoxanthin (6.10 mg per g dw), and relevant β-carotene and Coenzyme Q10 contents were detected. I. galbana aqueous extracts presented a high antioxidant capacity (approximately 90% inhibition by the ABTS method). Furthermore, I. galbana biomass and ethanolic extract showed significant cytotoxicity against HeLa human cervical cancer cells, with IC₅₀ values of 0.32 and 0.28 mg ml^-1 respectively, demonstrating potential for further anticancer studies. The aqueous extract of I. galbana induced a significant decrease of cholesterol absorption through Caco-2 monolayers, modelling the human intestinal barrier, which suggests that it may contribute to decreasing the dietary cholesterol absorption.

Are hypohydrated older adults at increased risk of exhaustion?

BACKGROUND

Dehydration appears to affect muscle strength and weakness, although its influence on exhaustion remains unclear. The present study aimed to quantify the association between hydration status and exhaustion among older adults.

METHODS

A cluster sampling approach was used, representing Portuguese older adults (≥65 years) according to age, sex, education level and region within the Nutrition UP65 cross-sectional study. A 24-h urine sample was collected to estimate free water reserve (FWR), which was categorised into tertiles according to sex. Subjects with incomplete 24-h urine and renal disease were excluded. From a sample size of 1500 subjects, 1143 were eligible. Exhaustion was self-reported according to the Center for Epidemiologic Studies Depression Scale. A logistic regression model was conducted to evaluate the association between FWR and exhaustion. Odds ratios and the respective 95% confidence intervals were calculated by sex and age.

RESULTS

Free water reserve median (interquartile range) was 0.52 (0.68) L in women and 0.36 (0.77) L in men. Hypohydration affected 11.6% of women and 25.1% of men, whereas exhaustion was reported by 39.3% of women and 25.1% of men. After adjusting for confounders, women ≥80 years classified in the highest tertile of FWR showed a decreased risk of exhaustion (third tertile: odds ratio = 0.38; 95% confidence interval = 0.15-0.96) compared to women in the lowest FWR tertile. No such significant association was observed in women with <80 years and in men.

CONCLUSIONS

These results show an association between worse hydration status and exhaustion in older women, highlighting the need to implement further studies clarifying this association.

Chalcone derivatives targeting mitosis: synthesis, evaluation of antitumor activity and lipophilicity

This study describes the synthesis of a series of chalcones, including pyrazole and α,β-epoxide derivatives, and evaluation of their cell growth inhibitory activity in three human tumor cell lines, as well as their lipophilicity using liposomes as a biomimetic membrane model. Structure-activity and structure-lipophilicity relationships were established for the synthetized chalcones. From this work, nine chalcones (3, 5, 9, 11, 15-19) showing suitable drug-like lipophilicity with potent growth inhibitory activity were identified, being the growth inhibitory effect of compounds 15-17 associated with a pronounced antimitotic effect. Compounds 15-17 affected spindle assembly and, as a consequence, arrested cells at metaphase in NCI-H460 cells, culminating in cell death. Amongst the compounds tested, compound 15 exhibited the highest antimitotic activity as revealed by mitotic index calculation. Moreover, 15 was able to enhance chemosensitivity of tumor cells to low doses of paclitaxel in NCI-H460 cells. The results indicate that 15 exerts its antiproliferative activity by affecting microtubules and causing cell death subsequently to a mitotic arrest, and thus has the potential for antitumor activity.