38 research outputs found
Illness perception and related behaviour in lower respiratory tract infections—a European study
Background. Lower respiratory tract infection (LRTI) is a common presentation in primary care, but little is known about associated patients’ illness perception and related behaviour. Objective. To describe illness perceptions and related behaviour in patients with LRTI visiting their general practitioner (GP) and identify differences between European regions and types of health care system. Methods. Adult patients presenting with acute cough were included. GPs recorded co morbidities and clinical findings. Patients filled out a diary for up to 4 weeks on their symptoms, illness perception and related behaviour. The chi-square test was used to compare proportions between groups and the Mann-Whitney U or Kruskal Wallis tests were used to compare means. Results. Three thousand one hundred six patients from 12 European countries were included. Eighty-one per cent (n = 2530) of the patients completed the diary. Patients were feeling unwell for a mean of 9 (SD 8) days prior to consulting. More than half experienced impairment of normal or social activities for at least 1 week and were absent from work/school for a mean of 4 (SD 5) days. On average patients felt recovered 2 weeks after visiting their GP, but 21% (n = 539) of the patients did not feel recovered after 4 weeks. Twenty-seven per cent (n = 691) reported feeling anxious or depressed, and 28% (n = 702) re-consulted their GP at some point during the illness episode. Reported illness duration and days absent from work/school differed between countries and regions (North-West versus South-East), but there was little difference in reported illness course and related behaviour between health care systems (direct access versus gate-keeping). Conclusion. Illness course, perception and related behaviour in LRTI differ considerably between countries. These finding should be taken into account when developing International guidelines for LRTI and interventions for setting realistic expectations about illness course
Entamoeba and Giardia parasites implicated as hosts of CRESS viruses.
Metagenomic techniques have enabled genome sequencing of unknown viruses without isolation in cell culture, but information on the virus host is often lacking, preventing viral characterisation. High-throughput methods capable of identifying virus hosts based on genomic data alone would aid evaluation of their medical or biological relevance. Here, we address this by linking metagenomic discovery of three virus families in human stool samples with determination of probable hosts. Recombination between viruses provides evidence of a shared host, in which genetic exchange occurs. We utilise networks of viral recombination to delimit virus-host clusters, which are then anchored to specific hosts using (1) statistical association to a host organism in clinical samples, (2) endogenous viral elements in host genomes, and (3) evidence of host small RNA responses to these elements. This analysis suggests two CRESS virus families (Naryaviridae and Nenyaviridae) infect Entamoeba parasites, while a third (Vilyaviridae) infects Giardia duodenalis. The trio supplements five CRESS virus families already known to infect eukaryotes, extending the CRESS virus host range to protozoa. Phylogenetic analysis implies CRESS viruses infecting multicellular life have evolved independently on at least three occasions
Bone Marrow Stromal Cells Modulate Mouse ENT1 Activity and Protect Leukemia Cells from Cytarabine Induced Apoptosis
BACKGROUND: Despite a high response rate to chemotherapy, the majority of patients with acute myeloid leukemia (AML) are destined to relapse due to residual disease in the bone marrow (BM). The tumor microenvironment is increasingly being recognized as a critical factor in mediating cancer cell survival and drug resistance. In this study, we propose to identify mechanisms involved in the chemoprotection conferred by the BM stroma to leukemia cells. METHODS: Using a leukemia mouse model and a human leukemia cell line, we studied the interaction of leukemia cells with the BM microenvironment. We evaluated in vivo and in vitro leukemia cell chemoprotection to different cytotoxic agents mediated by the BM stroma. Leukemia cell apoptosis was assessed by flow cytometry and western blotting. The activity of the equilibrative nucleoside transporter 1 (ENT1), responsible for cytarabine cell incorporation, was investigated by measuring transport and intracellular accumulation of (3)H-adenosine. RESULTS: Leukemia cell mobilization from the bone marrow into peripheral blood in vivo using a CXCR4 inhibitor induced chemo-sensitization of leukemia cells to cytarabine, which translated into a prolonged survival advantage in our mouse leukemia model. In vitro, the BM stromal cells secreted a soluble factor that mediated significant chemoprotection to leukemia cells from cytarabine induced apoptosis. Furthermore, the BM stromal cell supernatant induced a 50% reduction of the ENT1 activity in leukemia cells, reducing the incorporation of cytarabine. No protection was observed when radiation or other cytotoxic agents such as etoposide, cisplatin and 5-fluorouracil were used. CONCLUSION: The BM stroma secretes a soluble factor that significantly protects leukemia cells from cytarabine-induced apoptosis and blocks ENT1 activity. Strategies that modify the chemo-protective effects mediated by the BM microenvironment may enhance the benefit of conventional chemotherapy for patients with AML
Classroom quality at pre-kindergarten and kindergarten and children's social skills and behavior problems
Focusing on the continuity in the quality of classroom environments as children transition from preschool into elementary school, this study examined the associations between classroom quality in pre-kindergarten and kindergarten and children's social skills and behavior problems in kindergarten and first grade. Participants included 1175 ethnically-diverse children (43% African American) living in low-wealth rural communities of the US. Results indicated that children who experienced higher levels of emotional and organizational classroom quality in both pre-kindergarten and kindergarten demonstrated better social skills and fewer behavior problems in both kindergarten and first grade comparing to children who did not experience higher classroom quality. The examination of the first grade results indicated that the emotional and organizational quality of pre-kindergarten classrooms was the strongest predictor of children's first grade social skills and behavior problems. The study results are discussed from theoretical, practical, and policy perspectives
Classroom quality at pre-kindergarten and kindergarten and children's social skills and behavior problems
Focusing on the continuity in the quality of classroom environments as children transition from preschool into elementary school, this study examined the associations between classroom quality in pre-kindergarten and kindergarten and children's social skills and behavior problems in kindergarten and first grade. Participants included 1175 ethnically-diverse children (43% African American) living in low-wealth rural communities of the US. Results indicated that children who experienced higher levels of emotional and organizational classroom quality in both pre-kindergarten and kindergarten demonstrated better social skills and fewer behavior problems in both kindergarten and first grade comparing to children who did not experience higher classroom quality. The examination of the first grade results indicated that the emotional and organizational quality of pre-kindergarten classrooms was the strongest predictor of children's first grade social skills and behavior problems. The study results are discussed from theoretical, practical, and policy perspectives
The CCL2/CCR2 Axis Affects Transmigration and Proliferation but Not Resistance to Chemotherapy of Acute Myeloid Leukemia Cells.
Acute myeloid leukemia (AML) has a high mortality rate despite chemotherapy and transplantation. Both CXCR4/SDF-1 and VLA-4/VCAM1 axes are involved in leukemia protection but little is known about the role of CCL2/CCR2 in AML biology and protection against chemotherapy. We measured CCR2 expression in AML cell lines and primary AML cells by flow cytometry (FCM), real time PCR (RT-PCR) and western blot (WB). CCL2 production was quantified by solid phase ELISA in peripheral blood (PB) and bone marrow (BM) serum. We measured chemotaxis in a transwell system with different concentrations of CCL2/CCR2 blockers; cell cycle with BrDU and propidium iodide and proliferation with yellow tetrazolium MTT. We determined synergy in in vitro cell apoptosis combining chemotherapy and CCL2/CCR2 blockade. Finally, we performed chemoprotection studies in an in vivo mouse model. Of 35 patients, 23 (65%) expressed CCR2 by FCM in PB. Two cell lines expressed high levels of CCR2 (THP-1 and murine AML). RT-PCR and WB confirmed CCR2 production. CCL2 solid phase ELISA showed significantly lower levels of CCL2 in PB and BM compared to normal controls. Chemotaxis experiments confirmed a dose-dependent migration in AML primary cells expressing CCR2 and THP-1 cells. A significant inhibition of transmigration was seen after CCL2/CCR2 blockade. Proliferation of CCR2+ AML cell lines was slightly increased (1.4-fold) after axis stimulation. We observed a non-significant increase in phase S THP-1 cells exposed to CCL2 and a concomitant decrease of cells in G1. The chemotherapy studies did not show a protective effect of CCL2 on cytarabine-induced apoptosis or synergy with chemotherapy after CCL2/CCR2 blockade both in vitro and in vivo. In conclusion, CCL2/CCR2 axis is expressed in the majority of monocytoid AML blasts. The axis is involved in cell trafficking and proliferation but no in vitro and in vivo chemotherapy protective effect was seen
Host prediction for disease-associated gastrointestinal cressdnaviruses
Metagenomic techniques have facilitated the discovery of thousands of viruses, yet because samples are often highly biodiverse, fundamental data on the specific cellular hosts are usually missing. Numerous gastrointestinal viruses linked to human or animal diseases are affected by this, preventing research into their medical or veterinary importance. Here, we developed a computational workflow for the prediction of viral hosts from complex metagenomic datasets. We applied it to seven lineages of gastrointestinal cressdnaviruses using 1,124 metagenomic datasets, predicting hosts of four lineages. The Redondoviridae, strongly associated to human gum disease (periodontitis), were predicted to infect Entamoeba gingivalis, an oral pathogen itself involved in periodontitis. The Kirkoviridae, originally linked to fatal equine disease, were predicted to infect a variety of parabasalid protists, including Dientamoeba fragilis in humans. Two viral lineages observed in human diarrhoeal disease (CRESSV1 and CRESSV19, i.e. pecoviruses and hudisaviruses) were predicted to infect Blastocystis spp. and Endolimax nana respectively, protists responsible for millions of annual human infections. Our prediction approach is adaptable to any virus lineage and requires neither training datasets nor host genome assemblies. Two host predictions (for the Kirkoviridae and CRESSV1 lineages) could be independently confirmed as virus–host relationships using endogenous viral elements identified inside host genomes, while a further prediction (for the Redondoviridae) was strongly supported as a virus–host relationship using a case–control screening experiment of human oral plaques
Entamoeba and Giardia parasites implicated as hosts of CRESS viruses
Metagenomic techniques have enabled genome sequencing of unknown viruses without isolation in cell culture, but information on the virus host is often lacking, preventing viral characterisation. High-throughput methods capable of identifying virus hosts based on genomic data alone would aid evaluation of their medical or biological relevance. Here, we address this by linking metagenomic discovery of three virus families in human stool samples with determination of probable hosts. Recombination between viruses provides evidence of a shared host, in which genetic exchange occurs. We utilise networks of viral recombination to delimit virus-host clusters, which are then anchored to specific hosts using (1) statistical association to a host organism in clinical samples, (2) endogenous viral elements in host genomes, and (3) evidence of host small RNA responses to these elements. This analysis suggests two CRESS virus families (Naryaviridae and Nenyaviridae) infect Entamoeba parasites, while a third (Vilyaviridae) infects Giardia duodenalis. The trio supplements five CRESS virus families already known to infect eukaryotes, extending the CRESS virus host range to protozoa. Phylogenetic analysis implies CRESS viruses infecting multicellular life have evolved independently on at least three occasions
Validation of the Visual/Verbal Analogue Scale of Food Ingesta (Ingesta-VVAS) in Oncology Patients Undergoing Chemotherapy
This study aimed to: (1) externally validate the Visual/Verbal Analogue Scale of food ingesta (ingesta-VVAS) that previously showed good discrimination between oncology patients who ingest more or less energy than required; (2) explore the discriminative properties of other questions. Dietitians performed 322 interviews in 206 adult oncology patients undergoing chemotherapy in two Dutch hospitals, including a 24-h dietary recall, assessment of the ingesta-VVAS and 12 additional questions related to reduced food intake. The ingesta-VVAS score was linearly associated with energy intake as % of Total Energy Expenditure (TEE) (standardized beta = 0.39, p < 0.001), with no differences between groups based on use of oral nutritional supplements, body mass index, in/outpatient setting or sex. The accuracy of the ingesta-VVAS score to predict low energy intake (<75% of TEE) was poor (Area Under the Receiver Operating Characteristic curve (AUC) = 0.668, 95% CI 0.603–0.733). The optimal multivariate model included the ingesta-VVAS score and a question on ‘feeling sick’ (AUC = 0.680, 95% CI 0.615–0.746). In conclusion, in our study the ingesta-VVAS discriminates poorly between oncology patients undergoing chemotherapy who ingest more or less energy than required. Adding a question on feeling sick only slightly improved model performance. Further external validation is warranted
Laboratory evaluation of the miniature direct-on-blood PCR nucleic acid lateral flow immunoassay (mini-dbPCR-NALFIA), a simplified molecular diagnostic test for Plasmodium
Background: Point-of-care diagnosis of malaria is currently based on microscopy and rapid diagnostic tests. However, both techniques have their constraints, including poor sensitivity for low parasitaemias. Hence, more accurate diagnostic tests for field use and routine clinical settings are warranted. The miniature direct-on-blood PCR nucleic acid lateral flow immunoassay (mini-dbPCR-NALFIA) is an innovative, easy-to-use molecular assay for diagnosis of malaria in resource-limited settings. Unlike traditional molecular methods, mini-dbPCR-NALFIA does not require DNA extraction and makes use of a handheld, portable thermal cycler that can run on a solar-charged power pack. Result read-out is done using a rapid lateral flow strip enabling differentiation of Plasmodium falciparum and non-falciparum malaria infections. A laboratory evaluation was performed to assess the performance of the mini-dbPCR-NALFIA for diagnosis of pan-Plasmodium and P. falciparum infections in whole blood. Methods: Diagnostic accuracy of the mini-dbPCR-NALFIA was determined by testing a set of Plasmodium-positive blood samples from returned travellers (n = 29), and Plasmodium-negative blood samples from travellers with suspected malaria (n = 23), the Dutch Blood Bank (n = 19) and intensive care patients at the Amsterdam University Medical Centers (n = 16). Alethia Malaria (LAMP) with microscopy for species differentiation were used as reference. Limit of detection for P. falciparum was determined by 23 measurements of a dilution series of a P. falciparum culture. A fixed sample set was tested three times by the same operator to evaluate the repeatability, and once by five different operators to assess the reproducibility. Results: Overall sensitivity and specificity of the mini-dbPCR-NALFIA were 96.6% (95% CI, 82.2%–99.9%) and 98.3% (95% CI, 90.8%–100%). Limit of detection for P. falciparum was 10 parasites per microlitre of blood. The repeatability of the assay was 93.7% (95% CI, 89.5%–97.8%) and reproducibility was 84.6% (95% CI, 79.5%–89.6%). Conclusions: Mini-dbPCR-NALFIA is a sensitive, specific and robust method for molecular diagnosis of Plasmodium infections in whole blood and differentiation of P. falciparum. Incorporation of a miniature thermal cycler makes the assay well-adapted to resource-limited settings. A phase-3 field trial is currently being conducted to evaluate the potential implementation of this tool in different malaria transmission areas