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BackgroundTo inform future preventive measures including repeated vaccinations, we have searched for a clinically useful immune correlate of protection against fatal Covid-19 among nursing homes residents.MethodsWe performed repeated capillary blood sampling with analysis of S-binding IgG in an open cohort study with inclusion of nursing home residents in Sweden. We analyzed immunological and registry data collected from September 2021 with end of follow-up 31 August 2022. The study period included implementation of the 3rd and 4th mRNA monovalent vaccine doses and Omicron virus waves.FindingsA total of 3012 nursing home residents with median age 86 were enrolled. The 3rd mRNA dose elicited a 99-fold relative increase of S-binding IgG among 2606 blood-sampled individuals and corresponding increase of neutralizing antibodies. The 4th mRNA vaccine dose boosted the levels 3.8-fold. Half-life of S-binding IgG was 72 days. A total 528 residents acquired their first SARS-CoV-2 infection after the 3rd or the 4th vaccine dose and the 30-day mortality was 9.1%. We found no indication that levels of vaccine-induced antibodies protected against infection with Omicron VOCs. In contrast, the risk of death was inversely correlated to levels of S-directed IgG below the 20thpercentile. The risk plateaued at population average above lower 35th percentile of S-binding IgG.InterpretationIn the absence of neutralizing antibodies that protection from infection, quantification of S-binding IgG post vaccination may be useful to identify the most vulnerable for fatal Covid-19 among the oldest and frailest. This information is of importance for future strategies to protect vulnerable populations against neutralization resistant variants of concern.FundingSwedish Research Council, SciLife, Knut and Alice Wallenberg Foundation and Vinnova.

BackgroundWe have previously shown that lungs from deceased COVID-19 patients are filled with hyaluronan (HA). In this translational study, we investigated the role of HA in all stages of COVID-19 disease, to map the consequences of elevated HA in morbidity and identify the mechanism of SARS-CoV-2-induced HA production.MethodsLung morphology was visualized in 3D using light-sheet fluorescence microscopy. HA was verified by immunohistochemistry, and fragmentation was determined by gas-phase electrophoretic molecular mobility analysis. The association of systemic HA in blood plasma and disease severity was assessed in patients with mild (WHO Clinical Progression Scale, WHO-CPS, 1-5) and severe COVID-19 (WHO-CPS 6-9), during the acute and convalescent phases and related to lung function.In vitro3D-lung models differentiated from primary human bronchial epithelial cells were used to study effects of SARS-CoV-2 infection on HA metabolism.FindingsLungs of deceased COVID-19 patients displayed reduced alveolar surface area compared to healthy controls. We verified HA in alveoli and showed high levels of fragmented HA both in lung tissue and aspirates. Systemic levels of HA were high during acute COVID-19 disease, remained elevated during convalescence and associated with reduced diffusion capacity. Transcriptomic analysis of SARS-CoV-2-infected lung models showed dysregulation of HA synthases and hyaluronidases, both contributing to increased HA in apical secretions. Corticosteroid treatment reduced inflammation and, also, downregulated HA synthases.InterpretationWe show that HA plays a role in COVID-19 morbidity and that sustained elevated HA concentrations may contribute to long-term respiratory impairment. SARS-CoV-2 infection triggers a dysregulation of HA production, leading to increased concentrations of HA that are partially counteracted by corticosteroid treatment. Treatments directly targeting HA production and/or degradation can likely be used early during infection and may alleviate disease progression and prevent long-term lung complications.

Background The current SARS-CoV-2 pandemic has highlighted a need for easy and safe blood sampling in combination with accurate serological methodology. Venipuncture for testing is usually performed by trained staff at healthcare centres. Long travel distances to healthcare centres in rural regions may introduce a bias of testing towards relatively large communities with closer access. Rural regions are therefore often not represented in population-based data. Aim The aim of this retrospective cohort study was to develop and implement a strategy for at-home testing in a rural region of Sweden during spring 2021, and to evaluate its role to provide equal health care for its inhabitants. Methods We developed a sensitive method to measure antibodies to the S-protein of SARS-CoV-2 and optimised this assay for clinical use together with a strategy of at-home capillary blood sampling. Results We demonstrated that our ELISA gave comparable results after analysis of capillary blood or serum from SARS-CoV-2-experienced individuals. We demonstrated stability of the assay under conditions that reflected temperature and humidity during winter or summer. By assessment of capillary blood samples from 4,122 individuals, we could show both feasibility of the strategy and that implementation shifted the geographical spread of testing in favour of rural areas. Conclusion Implementation of at-home sampling enabled citizens living in remote rural areas access to centralised and sensitive laboratory antibody tests. The strategy for testing used here could therefore enable disease control authorities to get rapid access to information concerning immunity to infectious diseases, even across vast geographical distance.

BACKGROUND: The SARS-CoV-2 pandemic is a worldwide challenge. The CRIT-CoV-U pilot study generated a urinary proteomic biomarker consisting of 50 peptides (COV50), which predicted death and disease progression from SARS-CoV-2. After the interim analysis presented for the German Government, here, we aimed to analyse the full dataset to consolidate the findings and propose potential clinical applications of this biomarker. METHODS: CRIT-CoV-U was a prospective multicentre cohort study. In eight European countries (Austria, France, Germany, Greece, North Macedonia, Poland, Spain, and Sweden), 1012 adults with PCR-confirmed COVID-19 were followed up for death and progression along the 8-point WHO scale. Capillary electrophoresis coupled with mass spectrometry was used for urinary proteomic profiling. Statistical methods included logistic regression and receiver operating characteristic curve analysis with a comparison of the area under curve (AUC) between nested models. Hospitalisation costs were derived from the care facility corresponding with the Markov chain probability of reaching WHO scores ranging from 3 to 8 and flat-rate hospitalisation costs adjusted for the gross per capita domestic product of each country. FINDINGS: From June 30 to Nov 19, 2020, 228 participants were recruited, and from April 30, 2020, to April 14, 2021, 784 participants were recruited, resulting in a total of 1012 participants. The entry WHO scores were 1-3 in 445 (44%) participants, 4-5 in 529 (52%) participants, and 6 in 38 (4%) participants; and of all participants, 119 died and 271 had disease progression. The odds ratio (OR) associated with COV50 in all 1012 participants for death was 2·44 (95% CI 2·05-2·92) unadjusted and 1·67 (1·34-2·07) when adjusted for sex, age, BMI, comorbidities, and baseline WHO score; and for disease progression, the OR was 1·79 (1·60-2·01) when unadjusted and 1·63 (1·41-1·91) when adjusted (p

Background: To inform future preventive measures including repeated vaccinations, we have searched for a clinically useful immune correlate of protection against fatal COVID-19 among nursing homes residents. Methods: We performed repeated capillary blood sampling with analysis of S-binding IgG in an open cohort of nursing home residents in Sweden. We analyzed immunological and registry data from 16 September 2021 to 31 August 2022 with follow-up of deaths to 30 September 2022. The study period included implementation of the 3rd and 4th mRNA monovalent vaccine doses and Omicron virus waves. Findings: A total of 3012 nursing home residents with median age 86 were enrolled. The 3rd mRNA dose elicited a 99-fold relative increase of S-binding IgG in blood and corresponding increase of neutralizing antibodies. The 4th mRNA vaccine dose boosted levels 3.8-fold. Half-life of S-binding IgG was 72 days. A total 528 residents acquired their first SARS-CoV-2 infection after the 3rd or the 4th vaccine dose and the associated 30-day mortality was 9.1%. We found no indication that levels of vaccine-induced antibodies protected against infection with Omicron VOCs. In contrast, the risk of death was inversely correlated to levels of S-directed IgG below the 20th percentile. The death risk plateaued at population average above the lower 35th percentile of S-binding IgG. Interpretation: In the absence of neutralizing antibodies that protect from infection, quantification of S-binding IgG post vaccination may be useful to identify the most vulnerable for fatal COVID-19 among the oldest and frailest. This information is of importance for future strategies to protect vulnerable populations against neutralization resistant variants of concern.

Most entities studied by archaeologists share the same basic necessary conditions. They are limited spatiotemporal units which are continuous within a human frame of sensorial reference. These en­ tities cannot dissolve into their constituent parts without affecting their function, capacity, and mor­ phology. Further, they usually occupy one phys­ ical state at a time. The hyperfact, on the other hand, is vastly distributed, it can dissolve into most of its parts without affecting its “essence”, and it can be in several physical states at the same time. Water is a typical hyperfact, existing on multiple scales, from molecules to the hydrological cycle. In this text I show how local manifestations of this hyperfact can be found in ceramics, architectural features, agriculture, water management systems, and regional settlements of the Cochuah region in southern Mexico.

Understanding immune responses after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) breakthrough infection will facilitate the development of next-generation vaccines. Here, we profiled spike (S)–specific B cell responses after Omicron/BA.1 infection in messenger RNA–vaccinated donors. The acute antibody response was characterized by high levels of somatic hypermutation and a bias toward recognition of ancestral SARS-CoV-2 strains, suggesting the early activation of vaccine-induced memory B cells. BA.1 breakthrough infection induced a shift in B cell immunodominance hierarchy from the S2 subunit, which is highly conserved across SARS-CoV-2 variants of concern (VOCs), and toward the antigenically variable receptor binding domain (RBD). A large proportion of RBD-directed neutralizing antibodies isolated from BA.1 breakthrough infection donors displayed convergent sequence features and broadly recognized SARS-CoV-2 VOCs. Together, these findings provide insights into the role of preexisting immunity in shaping the B cell response to heterologous SARS-CoV-2 variant exposure.

To identify circulating proteins influencing Coronavirus Disease 2019 (COVID-19) susceptibility and severity, we undertook a two-sample Mendelian randomization (MR) study, rapidly scanning hundreds of circulating proteins while reducing bias due to reverse causation and confounding. In up to 14,134 cases and 1.2 million controls, we found that an s.d. increase in OAS1 levels was associated with reduced COVID-19 death or ventilation (odds ratio (OR) = 0.54, P = 7 × 10−8), hospitalization (OR = 0.61, P = 8 × 10−8) and susceptibility (OR = 0.78, P = 8 × 10−6). Measuring OAS1 levels in 504 individuals, we found that higher plasma OAS1 levels in a non-infectious state were associated with reduced COVID-19 susceptibility and severity. Further analyses suggested that a Neanderthal isoform of OAS1 in individuals of European ancestry affords this protection. Thus, evidence from MR and a case–control study support a protective role for OAS1 in COVID-19 adverse outcomes. Available pharmacological agents that increase OAS1 levels could be prioritized for drug development. A variant of the OAS1 gene, which encodes an enzyme that is critical for the innate immune response to viral infections, is associated with decreased risk of death in patients with COVID-19.

Understanding immune responses following SARS-CoV-2 breakthrough infection will facilitate the development of next-generation vaccines. Here, we profiled spike (S)-specific B cell responses following Omicron/BA.1 infection in mRNA-vaccinated donors. The acute antibody response was characterized by high levels of somatic hypermutation (SHM) and a bias toward recognition of ancestral SARS-CoV-2 strains, suggesting the early activation of vaccine-induced memory B cells (MBCs). BA.1 breakthrough infection induced a shift in B cell immunodominance hierarchy from the S2 subunit toward the receptor binding domain (RBD). A large proportion of RBD-directed neutralizing antibodies isolated from BA.1 breakthrough infection donors displayed convergent sequence features and broadly recognized SARS-CoV-2 variants of concern (VOCs). Together, these findings provide fundamental insights into the role of pre-existing immunity in shaping the B cell response to heterologous SARS-CoV-2 variant exposure.One sentence summaryBA.1 breakthrough infection activates pre-existing memory B cells with broad activity against SARS-CoV-2 variants.

Heterologous prime-boost immunization strategies have the potential to augment COVID-19 vaccine efficacy. We longitudinally profiled severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S)–specific serological and memory B cell (MBC) responses in individuals who received either homologous (ChAdOx1:ChAdOx1) or heterologous (ChAdOx1:mRNA-1273) prime-boost vaccination. Heterologous messenger RNA (mRNA) booster immunization induced higher serum neutralizing antibody and MBC responses against SARS-CoV-2 variants of concern (VOCs) compared with that of homologous ChAdOx1 boosting. Specificity mapping of circulating B cells revealed that mRNA-1273 boost immunofocused ChAdOx1-primed responses onto epitopes expressed on prefusion-stabilized S. Monoclonal antibodies isolated from mRNA-1273–boosted participants displayed overall higher binding affinities and increased breadth of reactivity against VOCs relative to those isolated from ChAdOx1-boosted individuals. Overall, the results provide molecular insight into the enhanced quality of the B cell response induced after heterologous mRNA booster vaccination.

Heterologous prime-boost immunization strategies have the potential to augment COVID-19 vaccine efficacy and address ongoing vaccine supply challenges. Here, we longitudinally profiled SARS-CoV-2 spike (S)-specific serological and memory B cell (MBC) responses in individuals receiving either homologous (ChAdOx1:ChAdOx1) or heterologous (ChAdOx1:mRNA-1273) prime-boost vaccination. Heterologous mRNA booster immunization induced significantly higher serum neutralizing antibody and MBC responses compared to homologous ChAdOx1 boosting. Specificity mapping of circulating S-specific B cells revealed that mRNA-1273 booster immunization dramatically immunofocused ChAdOx1-primed responses onto epitopes expressed on prefusion-stabilized S. Monoclonal antibodies isolated from mRNA-1273-boosted participants displayed higher binding affinities and increased breadth of reactivity against variants of concern (VOCs) relative to those isolated from ChAdOx1-boosted participants. Overall, the results provide fundamental insights into the B cell response induced by ChAdOx1 and a molecular basis for the enhanced immunogenicity observed following heterologous mRNA booster vaccination.

Heterologous Vaccination with ChAdOx1 nCoV-19 and mRNA-1273 Health care workers who had received a dose of ChAdOx1 nCoV-19 were offered a choice of receiving either ChAdOx1 nCoV-19 or mRNA-1273 9 t...

Understanding the presence and durability of antibodies against SARS-CoV-2 in the airways is required to provide insights into the ability of individuals to neutralize the virus locally and prevent viral spread. Here, we longitudinally assessed both systemic and airway immune responses upon SARS-CoV-2 infection in a clinically well-characterized cohort of 147 infected individuals representing the full spectrum of COVID-19 severity, from asymptomatic infection to fatal disease. In addition, we evaluated how SARS-CoV-2 vaccination influenced the antibody responses in a subset of these individuals during convalescence as compared with naive individuals. Not only systemic but also airway antibody responses correlated with the degree of COVID-19 disease severity. However, although systemic IgG levels were durable for up to 8 months, airway IgG and IgA declined significantly within 3 months. After vaccination, there was an increase in both systemic and airway antibodies, in particular IgG, often exceeding the levels found during acute disease. In contrast, naive individuals showed low airway antibodies after vaccination. In the former COVID-19 patients, airway antibody levels were significantly elevated after the boost vaccination, highlighting the importance of prime and boost vaccinations for previously infected individuals to obtain optimal mucosal protection.

Proteins detectable in peripheral blood may influence COVID-19 susceptibility or severity. However, understanding which circulating proteins are etiologically involved is difficult because their levels may be influenced by COVID-19 itself and are also subject to confounding factors. To identify circulating proteins influencing COVID-19 susceptibility and severity we undertook a large-scale two-sample Mendelian randomization (MR) study, since this study design can rapidly scan hundreds of circulating proteins and reduces bias due to reverse causation and confounding. We identified genetic determinants of 931 circulating proteins in 28,461 SARS-CoV-2 uninfected individuals, retaining only single nucleotide polymorphism near the gene encoding the circulating protein. We found that a standard deviation increase in OAS1 levels was associated with reduced COVID-19 death or ventilation (N = 4,336 cases / 623,902 controls; OR = 0.54, P = 7×10−8), COVID-19 hospitalization (N = 6,406 / 902,088; OR = 0.61, P = 8×10−8) and COVID-19 susceptibility (N = 14,134 / 1,284,876; OR = 0.78, P = 8×10−6). Results were consistent in multiple sensitivity analyses. We then measured OAS1 levels in 504 patients with repeated plasma samples (N=1039) with different COVID-19 outcomes and found that increased OAS1 levels in a non-infectious state were associated with protection against very severe COVID-19, hospitalization and susceptibility. Further analyses suggested that a Neanderthal isoform of OAS1 affords this protection. Thus, evidence from MR and a case-control study supported a protective role for OAS1 in COVID-19 outcomes. Available medicines, such as phosphodiesterase-12 inhibitors, increase OAS1 and could be explored for their effect on COVID-19 susceptibility and severity.

The current SARS-CoV-2 pandemic has highlighted a need for easy and safe blood sampling in combination with accurate serological methodology. Venipuncture is usually performed by trained staff at health care centers. Long travel distances may introduce a bias of testing towards relatively large communities with close access to health care centers. Rural regions may thus be overlooked. Here, we demonstrate a sensitive method to measure antibodies to the S-protein of SARS-CoV-2. We adapted and optimized this assay for clinical use together with capillary blood sampling to meet the geographical challenges of serosurveillance. Finally, we tested remote at-home capillary blood sampling together with centralized assessment of S-specific IgG in a rural region of northern Scandinavia that encompasses 55,185 sq kilometers. We conclude that serological assessment from capillary blood sampling gives comparable results as analysis of venous blood. Importantly, at-home sampling enabled citizens living in remote rural areas access to centralized and sensitive laboratory antibody tests.

Chromatographic systems coupled with mass spectrometry detection are widely used in biological studies investigating how levels of biomolecules respond to different internal and external stimuli. Such changes are normally expected to be of low magnitude and therefore all experimental factors that can influence the analysis need to be understood and minimized. Run order effect is commonly observed and constitutes a major challenge in chromatography-mass spectrometry based profiling studies that needs to be addressed before the biological evaluation of measured data is made. So far there is no established consensus, metric or method that quickly estimates the size of this effect. In this paper we demonstrate how orthogonal projections to latent structures (OPLS®) can be used for objective quantification of the run order effect in profiling studies. The quantification metric is expressed as the amount of variation in the experimental data that is correlated to the run order. One of the primary advantages with this approach is that it provides a fast way of quantifying run-order effect for all detected features, not only internal standards. Results obtained from quantification of run order effect as provided by the OPLS can be used in the evaluation of data normalization, support the optimization of analytical protocols and identification of compounds highly influenced by instrumental drift. The application of OPLS for quantification of run order is demonstrated on experimental data from plasma profiling performed on three analytical platforms: GCMS metabolomics, LCMS metabolomics and LCMS lipidomics.

Introduction: Treatment of MDRTB is complex: regimens require microbiological data; adverse events are frequent; availability of drugs and authorization for new drugs varies. The aim of this study was to scope the available national resources. Method: A survey to determine whether practising physicians could access MDRTB advice was sent to TBnet members by email. The ERS Office also contacted national respiratory societies. Questions included the name and contact details for their national advisory service, whether it was national policy to use the service for each patient with MDRTB and whether advice was required to access bedaquiline and delaminid. Results: 65 replies were received (14 were uninformative). 26/31 EU/EEA and 10/19 other countries in the WHO European Region were represented. 7 countries referred all MDRTB to a tertiary centre; 12 countries had tertiary referral centres that also gave advice to physicians treating MDRTB. 11 countries had an electronic system for advice, 6 with multidisciplinary team meetings to review patients’ progress. Lead clinicians were identified for a further 8 countries, one of which had no national advisory service and the other 7 had not responded by the time of abstract submission. For 18 (58%) countries, discussion of MDRTB by a national /regional committee was national policy and most (15/18) required consultation to use bedaquiline or delamanid. Electronic platforms had a wide range of functionality but few retained anonymised data and audited patient outcomes. Conclusion: MDRTB management is often concentrated in tertiary centres. Clinical governance, regarding audit and outcome, are at an early stage in managing MDRTB.

Modern profiling technologies enable us to obtain large amounts of data which can be used later for a comprehensive understanding of the studied system. Proper evaluation of such data is challenging, and cannot be carried out by bare analysis of separate data sets. Integrated approaches are necessary, because only data integration allows us to find correlation trends common for all studied data sets and reveal hidden structures not known a priori. This improves the understanding and interpretation of complex systems. Joint and Unique MultiBlock Analysis (JUMBA) is an analysis method based on the OnPLS-algorithm that decomposes a set of matrices into joint parts containing variations shared with other connected matrices and variations that are unique for each single matrix. Mapping unique variations is important from a data integration perspective, since it certainly cannot be expected that all variation co-varies. In this work we used JUMBA for the integrated analysis of lipidomic, metabolomic and oxylipins data sets obtained from profiling of plasma samples from children infected with P. falciparum malaria. P. falciparum is one of the primary contributors to childhood mortality and obstetric complications in the developing world, which makes the development of new diagnostic and prognostic tools, as well as a better understanding of the disease, of utmost importance. In the presented work, JUMBA made it possible to detect already known trends related to the disease progression, but also to discover new structures in the data connected to food intake and personal differences in metabolism. By separating the variation in each data set into joint and unique, JUMBA reduced the complexity of the analysis and facilitated the detection of samples and variables corresponding to specific structures across multiple data sets, and by doing this enabled fast interpretation of the studied system. All of this makes JUMBA a perfect choice for multiblock analysis of systems biology data.

The Chicxulub impact ~66 million years ago and subsequent geological processes have created different hydrogeological regimes in the Yucatan peninsula, Mexico. These regimes have affected settlement patterns on local and regional scales. This study focuses on the intersection between three of these regimes; the Buried Ejecta within Saline Intrusion Zone, the Albion Formation, and the Ticul Fault Zone. Lake Chichancanab is located in the intersection between these zones. The Prehispanic settlement east of Chichancanab, in the Cochuah region, is distributed evenly whereas the Colonial period settlement of the same area largely stays within the Buried Ejecta within Saline Intrusion Zone. Colonial socioeconomic conditions and the Church limited the Spanish control of the Cochuah region, partially because groundwater access became increasingly more important during the Colonial period. WIREs Water 2016, 3:871–884. doi: 10.1002/wat2.1170 For further resources related to this article, please visit the WIREs website.

From a cognitive perspective there are two different “regions” of time. These are experiential time and known time . Each one has multiple temporal scales and both are mutually irreducible. These different scales of time are needed to coordinate phenomena in regions of various magnitudes (molecules, cells, organisms, social groups, etc.). Experiential time is perceived to be continuous by our senses but there is a limit to this temporal reproduction. Durations longer than a minute need external devices to be known. The Maya calendars manifest known time and they were and still are designed to order the days, i.e. the passing of time. The calendars have been created from cognitive interaction with digits, aging, pregnancy, vegetative cycles, the sun and phases of the moon, the hydrological cycle, i.e. from objects and the events they generated. Once established these calendars have also affected the way time has been perceived individually and collectively. With the collapse of the institution of divine kingship during the 9–11th centuries AD, the accumulative time of the Long Count disappeared in favor of the cyclical Short Count. This change implies not just sociopolitical changes but also cognitive changes. Knowledge of earlier history and engagement with ruins and artefacts enforced an understanding of previous creations and their associations with repeated periods of time.

In her discussion article ‘Fluid consistencies. Material relationality in human engagements with water’, Veronica Strang argues that ‘water provides a useful focus for thinking aboutrelationshipsbetween things and persons and betweenmaterialproperties and meanings’ (Strang 2014, 133, emphasis added). Water permeates organic things and flows and connects in a multi-scalar way. Therefore her article emphasizes ‘how material and social processes combine to provide both fluidity and consistency at every level of human–non-human engagement’ (ibid., 133). Ontologically speaking, the emphasis on fluid relations and processes makes her arelationist, i.e. objects emerge from their internal or external relations (Harman 2009). I will summarize my reactions to her article in three major points.

The recent proposal of splitting the genus Borrelia into two genera in the newly formed family of Borreliaceae, i.aEuroe. Borrelia and Borreliella has motivated us to reflect upon how these organisms has been characterized and differentiated. This article therefore aims to take a closer look on the biology and virulence attributes of the two suggested genera, i.aEuroe. those causing Lyme borreliosis and relapsing fever borreliosis. Both genera have much in common with similar infection biological features. They are both characterized as bacterial zoonoses, transmitted by hematophagous arthropods with almost identical microbiological appearance. Nevertheless, a closer look at the genotypic and phenotypic characteristics clearly reveals several differences that might motivate the suggested split. On the other hand, a change of this well-established classification within the genus Borrelia might impose an economical burden as well as a great confusion in society, including medical and scientific societies as well as the general population.

Background Oxylipins and endocannabinoids are low molecular weight bioactive lipids that are crucial for initiation and resolution of inflammation during microbial infections. Metabolic complications in malaria are recognized contributors to severe and fatal malaria, but the impact of malaria infection on the production of small lipid derived signalling molecules is unknown. Knowledge of immunoregulatory patterns of these molecules in malaria is of great value for better understanding of the disease and improvement of treatment regimes, since the action of these classes of molecules is directly connected to the inflammatory response of the organism. Methods Detection of oxylipins and endocannabinoids from plasma samples from forty children with uncomplicated and severe malaria as well as twenty controls was done after solid phase extraction followed by chromatography mass spectrometry analysis. The stable isotope dilution method was used for compound quantification. Data analysis was done with multivariate (principal component analysis (PCA), orthogonal partial least squares discriminant analysis (OPLS-DA®) and univariate approaches (receiver operating characteristic (ROC) curves, t tests, correlation analysis). Results Forty different oxylipin and thirteen endocannabinoid metabolites were detected in the studied samples, with one oxylipin (thromboxane B2, TXB2) in significantly lower levels and four endocannabinoids (OEA, PEA, DEA and EPEA) at significantly higher levels in infected individuals as compared to controls according to t test analysis with Bonferroni correction. Three oxylipins (13-HODE, 9-HODE and 13-oxo-ODE) were higher in severe compared to uncomplicated malaria cases according to the results from multivariate analysis. Observed changes in oxylipin levels can be connected to activation of cytochrome P450 (CYP) and 5-lipoxygenase (5-LOX) metabolic pathways in malaria infected individuals compared to controls, and related to increased levels of all linoleic acid oxylipins in severe patients compared to uncomplicated ones. The endocannabinoids were extremely responsive to malaria infection with majority of this class of molecules found at higher levels in infected individuals compared to controls. Conclusions It was possible to detect oxylipin and endocannabinoid molecules that can be potential biomarkers for differentiation between malaria infected individuals and controls and between different classes of malaria. Metabolic pathways that could be targeted towards an adjunctive therapy in the treatment of malaria were also pinpointed. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-2001-y) contains supplementary material, which is available to authorized users.

Unmet needs persist in pediatric HIV programs : lessons from selected case studies in Uganda

Introduction: Several studies have observed serum lipid changes during malaria infection in humans. All of them were focused at analysis of lipoproteins, not specific lipid molecules. The aim of our study was to identify novel patterns of lipid species in malaria infected patients using lipidomics profiling, to enhance diagnosis of malaria and to evaluate biochemical pathways activated during parasite infection. Methods: Using a multivariate characterization approach, 60 samples were representatively selected, 20 from each category (mild, severe and controls) of the 690 study participants between age of 0.5–6 years. Lipids from patient’s plasma were extracted with chloroform/methanol mixture and subjected to lipid profiling with application of the LCMS-QTOF method. Results: We observed a structured plasma lipid response among the malaria-infected patients as compared to healthy controls, demonstrated by higher levels of a majority of plasma lipids with the exception of even-chain length lysophosphatidylcholines and triglycerides with lower mass and higher saturation of the fatty acid chains. An inverse lipid profile relationship was observed when plasma lipids were correlated to parasitaemia. Conclusions: This study demonstrates how mapping the full physiological lipid response in plasma from malaria-infected individuals can be used to understand biochemical processes during infection. It also gives insights to how the levels of these molecules relate to acute immune responses.

Introduction Several studies have observed serum lipid changes during malaria infection in humans. All of them were focused at analysis of lipoproteins, not specific lipid molecules. The aim of our study was to identify novel patterns of lipid species in malaria infected patients using lipidomics profiling, to enhance diagnosis of malaria and to evaluate biochemical pathways activated during parasite infection. Methods Using a multivariate characterization approach, 60 samples were representatively selected, 20 from each category (mild, severe and controls) of the 690 study participants between age of 0.5–6 years. Lipids from patient’s plasma were extracted with chloroform/methanol mixture and subjected to lipid profiling with application of the LCMS-QTOF method. Results We observed a structured plasma lipid response among the malaria-infected patients as compared to healthy controls, demonstrated by higher levels of a majority of plasma lipids with the exception of even-chain length lysophosphatidylcholines and triglycerides with lower mass and higher saturation of the fatty acid chains. An inverse lipid profile relationship was observed when plasma lipids were correlated to parasitaemia. Conclusions This study demonstrates how mapping the full physiological lipid response in plasma from malaria-infected individuals can be used to understand biochemical processes during infection. It also gives insights to how the levels of these molecules relate to acute immune responses. Electronic supplementary material The online version of this article (doi:10.1007/s11306-017-1174-2) contains supplementary material, which is available to authorized users.

Salicylidene acylhydrazides (SAHs) inhibit the type III secretion system (T3S) of Yersinia and other Gram-negative bacteria. In addition, SAHs restrict the growth and development of Chlamydia species. However, since the inhibition of Chlamydia growth by SAH is suppressed by the addition of excess iron and since SAHs have an iron-chelating capacity, their role as specific T3S inhibitors is unclear. We investigated here whether SAHs exhibit a function on C. trachomatis that goes beyond iron chelation. We found that the iron-saturated SAH INP0341 (IS-INP0341) specifically affects C. trachomatis infectivity with reduced generation of infectious elementary body (EB) progeny. Selection and isolation of spontaneous SAH-resistant mutant strains revealed that mutations in hemG suppressed the reduced infectivity caused by IS-INP0341 treatment. Structural modeling of C. trachomatis HemG predicts that the acquired mutations are located in the active site of the enzyme, suggesting that IS-INP0341 inhibits this domain of HemG and that protoporphyrinogen oxidase (HemG) and heme metabolism are important for C. trachomatis infectivity.