Interference of bovine hemoglobin-based oxygen carrier-201 (Hemopure) on four hematology analyzers

Introduction: Hemoglobin-based oxygen carriers, for example HBOC-201 (Hemopure), are aimed to bridge acute anemia when blood transfusion is not available or refused by the patient. However, since HBOC-201 appears free in plasma, it interferes with laboratory tests. This study presents an overview of HBOC-201 interference on four commonly used hematology analyzers and suggests treatment monitoring possibilities. Methods: Blood samples were spiked with therapeutic doses of HBOC-201 and nine hematology parameters were measured with the Sysmex XN-20, Siemens Advia 2120i, Abbott Alinity Hq and Abbot Cell Dyn Sapphire hematology analyzers. The results were compared to control samples and the bias was determined. Results: Most parameters, including all cell counts, hematocrit and MCV, showed a non-significant bias compared to control. However, the standard, total hemoglobin (Hb) measurement as well as MCH and MCHC showed poor agreement with control, as HBOC-201 was included in this measurement. Yet, the flow cytometry-based Hb method quantified intracellular Hb in spiked samples, excluding HBOC-201. Conclusion: Of all included hematology parameters, only total Hb and the associated MCH and MCHC suffered from interference. In contrast, the flow cytometry-based Hb measurement provided an accurate measure of intracellular Hb. The difference between total Hb and cellular Hb represents the HBOC-201 concentration and can be used to monitor HBOC-201 treatment.</p

Comparing the mitochondrial signatures in ESCs and iPSCs and their neural derivations

Under embargo until: 2023-07-10Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) have distinct origins: ESCs are derived from pre-implanted embryos while iPSCs are reprogrammed somatic cells. Both have their own characteristics and lineage specificity, and both are valuable tools for studying human neurological development and disease. Thus far, few studies have analyzed how differences between stem cell types influence mitochondrial function and mitochondrial DNA (mtDNA) homeostasis during differentiation into neural and glial lineages. In this study, we compared mitochondrial function and mtDNA replication in human ESCs and iPSCs at three different stages − pluripotent, neural progenitor and astrocyte. We found that while ESCs and iPSCs have a similar mitochondrial signature, neural and astrocyte derivations manifested differences. At the neural stem cell (NSC) stage, iPSC-NSCs displayed decreased ATP production and a reduction in mitochondrial respiratory chain (MRC) complex IV expression compared to ESC-NSCs. IPSC-astrocytes showed increased mitochondrial activity including elevated ATP production, MRC complex IV expression, mtDNA copy number and mitochondrial biogenesis relative to those derived from ESCs. These findings show that while ESCs and iPSCs are similar at the pluripotent stage, differences in mitochondrial function may develop during differentiation and must be taken into account when extrapolating results from different cell types.acceptedVersio

Convergent and discriminant validity of the Minimal Eating Observation Form - version II: a cross-sectional study

Background: The Minimal Eating Observation Form – Version II (MEOF-II) is a brief and easy to use screening tool for eating difficulties, that is psychometrically robust. The aim of this study was to explore convergent (measuring similar constructs) and discriminant (measuring somewhat different constructs) validity of the MEOF-II to other validated dysphagia specific, activity and participation related instruments. Methods: In this cross-sectional study, participants (n = 100, mean age 72, n = 42 women), diagnosed with either chronic pulmonary disease, Parkinson´s disease, Multiple Sclerosis, or stroke were recruited from rehabilitation centres. Patient-reported outcomes and clinical-rated assessments, capturing eating ability in general and swallowing in specific, included: The Dysphagia Handicap Index (DHI), the 4-question test (4QT), the Minimal Eating Observation Form – II, the Volume – Viscosity Swallow Test (V-VST), Flexible Endoscopic Evaluation of Swallowing (FEES) documented according to the Penetration-Aspiration Scale (PAS). Type of oral intake was documented using the Functional Oral Intake Scale (FOIS). Activities in daily living was assessed with Barthel index (BI). Spearman’s correlation coefficient was used to analyze associations. The MEOF-II total score was hypothesised to have moderate correlations (r ≥ 0.3) with the other assessments, besides with PAS and FOIS (weak correlations, r &lt; 0.3). Results: In total 78 participants had any type of eating difficulties (MEOF-II), 69 reported dysphagia (4QT), 62 had dysphagia according to V-VST, 29 showed evidence of penetration/aspiration (PAS), and 31 participants had decreased oral intake ability (FOIS). The MEOF-II total score had moderate correlations with DHI, BI, 4QT, V-VST volume, and weak correlations with V-VST dysphagia and viscosity, PAS, and FOIS. Comparing a prior hypothesised correlation strengths against empirical findings showed that 83% of the hypothesised correlations were correct. Conclusions: The MEOF-II is a holistic and objective screening tool that can indicate the need for further assessment and corresponds well with the persons’ subjective experiences. MEOF-II does not specifically assess the risk for penetration/aspiration.</p

POLG genotype influences degree of mitochondrial dysfunction in iPSC derived neural progenitors, but not the parent iPSC or derived glia

Diseases caused by POLG mutations are the most common form of mitochondrial diseases and associated with phenotypes of varying severity. Clinical studies have shown that patients with compound heterozygous POLG mutations have a lower survival rate than patients with homozygous mutations, but the molecular mechanisms behind this remain unexplored. Using an induced pluripotent stem cell (iPSC) model, we investigate differences between homozygous and compound heterozygous genotypes in different cell types, including patient-specific fibroblasts, iPSCs, and iPSC-derived neural stem cells (NSCs) and astrocytes. We found that compound heterozygous lines exhibited greater impairment of mitochondrial function in NSCs than homozygous NSCs, but not in fibroblasts, iPSCs, or astrocytes. Compared with homozygous NSCs, compound heterozygous NSCs exhibited more severe functional defects, including reduced ATP production, loss of mitochondrial DNA (mtDNA) copy number and complex I expression, disturbance of NAD+ metabolism, and higher ROS levels, which further led to cellular senescence and activation of mitophagy. RNA sequencing analysis revealed greater downregulation of mitochondrial and metabolic pathways, including the citric acid cycle and oxidative phosphorylation, in compound heterozygous NSCs. Our iPSC-based disease model can be widely used to understand the genotype-phenotype relationship of affected brain cells in mitochondrial diseases, and further drug discovery applications.publishedVersio

Effects of water availability and pest pressures on tea (Camellia sinensis) growth and functional quality

Extreme shifts in water availability linked to global climate change are impacting crops worldwide. The present study examines the direct and interactive effects of water availability and pest pressures on tea (Camellia sinensis; Theaceae) growth and functional quality. Manipulative greenhouse experiments were used to measure the effects of variable water availability and pest pressures simulated by jasmonic acid (JA) on tea leaf growth and secondary metabolites that determine tea quality. Water treatments were simulated to replicate ideal tea growing conditions and extreme precipitation events in tropical southwestern China, a major centre of tea production. Results show that higher water availability and JA significantly increased the growth of new leaves while their interactive effect was not significant. The effect of water availability and JA on tea quality varied with individual secondary metabolites. Higher water availability significantly increased total methylxanthine concentrations of tea leaves but there was no significant effect of JA treatments or the interaction of water and JA. Water availability, JA treatments or their interactive effects had no effect on the concentrations of epigallocatechin 3-gallate. In contrast, increased water availability resulted in significantly lower concentrations of epicatechin 3-gallate but the effect of JA and the interactive effects of water and JA were not significant. Lastly, higher water availability resulted in significantly higher total phenolic concentrations but there was no significant impact of JA and their interaction. These findings point to the fascinating dynamics of climate change effects on tea plants with offsetting interactions between precipitation and pest pressures within agro-ecosystems, and the need for future climate studies to examine interactive biotic and abiotic effects

Tick-borne pathogens of zoonotic and veterinary importance in Nigerian cattle

Additional file 1: Multiple infections by tick-borne pathogens according to age classes and overall number of animals. (PDF 19 kb)BACKGROUND : Ticks and tick-borne diseases undermine cattle fitness and productivity in the whole of sub-Saharan Africa, including Nigeria. In this West African country, cattle are challenged by numerous tick species, especially during the wet season. Consequently, several TBDs are known to be endemic in Nigerian cattle, including anaplasmosis, babesiosis, cowdriosis and theilerioris (by Theileria mutans and Theileria velifera). To date, all investigations on cattle TBDs in Nigeria have been based on cytological examinations and/or on serological methods. This study aimed to ascertain the occurrence of tick-borne pathogens of veterinary and zoonotic importance in cattle in Nigeria using molecular approaches. METHODS : In October 2008, 704 whole blood samples were collected from indigenous cattle in the Plateau State, Nigeria. Analysis for tick-borne pathogens was conducted by means of PCR-based reverse line blotting (RLB) and sequencing targeting a panel of five genera of microorganisms (i.e. Babesia, Theileria, Anaplasma, Ehrlichia and Rickettsia spp.). RESULTS : In total, 561/704 (82.6 %) animals were found infected, with 465 (69.6 %) of them being infected by two or more microorganisms, with up to 77 possible combinations of pathogens detected. Theileria mutans was the most prevalent microorganism (66.3 %), followed by Theileria velifera (52.4 %), Theileria taurotragi (39.5 %), Anaplasma marginale (39.1 %), Anaplasma sp. (Omatjenne) (34.7 %), Babesia bigemina (7.9 %), Anaplasma centrale (6.3 %), Anaplasma platys (3.9 %), Rickettsia massiliae (3.5 %), Babesia bovis (2.0 %) and Ehrlichia ruminantium (1.1 %). Calves were found significantly less infected than juvenile and adult cattle. CONCLUSIONS : This study provides updated, molecular-based information on cattle TBDs in Nigeria. The molecular approach employed allowed the diagnosis of numerous positive cases including carrier statuses, multiple infections and novel pathogen detections within the indigenous cattle population. Moreover, the RLB method here described enabled the detection of veterinary agents not only pertaining to bovine health, including also those of zoonotic importance. The high prevalence recorded for T. mutans, T. velifera, A. marginale, T. taurotragi and Anaplasma sp. (Omatjenne), suggests they may be endemically established in Nigeria, whereas the lower prevalence recorded for other microorganisms (i.e. A. centrale and B. bovis) highlights a less stable epidemiological scenario, requiring further investigations.The UK’s Biotechnology and Biological Sciences Research Council (BBSRC) under the ‘Combating Infectious Diseases in Livestock for International Development’ (CIDLID) scheme, and the European Union’s Seventh Framework Program (FP7/2007–2013) under grant agreement n° 221948, Integrated Control of Neglected Zoonoses (ICONZ).http://www.parasitesandvectors.comam2016Veterinary Tropical Disease

Dissecting quantitative trait variation in the resequencing era: complementarity of bi-parental, multi-parental and association panels

Quantitative trait loci (QTL) have been identified using traditional linkage mapping and positional cloning identified several QTLs. However linkage mapping is limited to the analysis of traits differing between two lines and the impact of the genetic background on QTL effect has been underlined. Genome-wide association studies (GWAs) were proposed to circumvent these limitations. In tomato, we have shown that GWAs is possible, using the admixed nature of cherry tomato genomes that reduces the impact of population structure. Nevertheless, GWAs success might be limited due to the low decay of linkage disequilibrium, which varies along the genome in this species. Multi-parent advanced generation intercross (MAGIC) populations offer an alternative to traditional linkage and GWAs by increasing the precision of QTL mapping. We have developed a MAGIC population by crossing eight tomato lines whose genomes were resequenced. We showed the potential of the MAGIC population when coupled with whole genome sequencing to detect candidate single nucleotide polymorphisms (SNPs) underlying the QTLs. QTLs for fruit quality traits were mapped and related to the variations detected at the genome sequence and expression levels. The advantages and limitations of the three types of population, in the context of the available genome sequence and resequencing facilities, are discussed.This work was supported by CEA-IG/CNG, by performing the DNA QC and providing access to INRA-EPGV to their Illumina Sequencing Platform. We acknowledge groups of Anne Boland (DNA and Cell Bank service) and Marie-Thérèse Bihoreau (Illumina HT Sequencing). The ANR MAGIC-Tom SNP project 09-GENM-109G and the European Solanaceae Integrated Project EUSOL (Food-CT-2006-016214) supported this work. LP was supported by a postdoctoral INRA fellowship, EA by an INRA PhD fellowship and JD by a grant from the Embassy of France in Thailand in Junior Research Fellowship Program 2014.Peer reviewe

Staphylococcus aureus infective endocarditis versus bacteremia strains: Subtle genetic differences at stake

AbstractInfective endocarditis (IE)(1) is a severe condition complicating 10–25% of Staphylococcus aureus bacteremia. Although host-related IE risk factors have been identified, the involvement of bacterial features in IE complication is still unclear. We characterized strictly defined IE and bacteremia isolates and searched for discriminant features. S. aureus isolates causing community-acquired, definite native-valve IE (n=72) and bacteremia (n=54) were collected prospectively as part of a French multicenter cohort. Phenotypic traits previously reported or hypothesized to be involved in staphylococcal IE pathogenesis were tested. In parallel, the genotypic profiles of all isolates, obtained by microarray, were analyzed by discriminant analysis of principal components (DAPC)(2). No significant difference was observed between IE and bacteremia strains, regarding either phenotypic or genotypic univariate analyses. However, the multivariate statistical tool DAPC, applied on microarray data, segregated IE and bacteremia isolates: IE isolates were correctly reassigned as such in 80.6% of the cases (C-statistic 0.83, P<0.001). The performance of this model was confirmed with an independent French collection IE and bacteremia isolates (78.8% reassignment, C-statistic 0.65, P<0.01). Finally, a simple linear discriminant function based on a subset of 8 genetic markers retained valuable performance both in study collection (86.1%, P<0.001) and in the independent validation collection (81.8%, P<0.01). We here show that community-acquired IE and bacteremia S. aureus isolates are genetically distinct based on subtle combinations of genetic markers. This finding provides the proof of concept that bacterial characteristics may contribute to the occurrence of IE in patients with S. aureus bacteremia