57 research outputs found
A Single-Molecule Bioelectronic Portable Array for Early Diagnosis of Pancreatic Cancer Precursors
A cohort of 47 patients is screened for pancreatic cancer precursors with a portable 96-well bioelectronic sensing-array for single-molecule assay in cysts fluid and blood plasma, deployable at point-of-care (POC). Pancreatic cancer precursors are mucinous cysts diagnosed with a sensitivity of at most 80% by state-of-the-art cytopathological molecular analyses (e.g., KRASmut DNA). Adding the simultaneous assay of proteins related to malignant transformation (e.g., MUC1 and CD55) is deemed essential to enhance diagnostic accuracy. The bioelectronic array proposed here, based on single-molecule-with-a-large-transistor (SiMoT) technology, can assay both nucleic acids and proteins at the single-molecule limit-of-identification (LOI) (1% of false-positives and false-negatives). It comprises an enzyme-linked immunosorbent assay (ELISA)-like 8 × 12-array organic-electronics disposable cartridge with an electrolyte-gated organic transistor sensor array, and a reusable reader, integrating a custom Si-IC chip, operating via software installed on a USB-connected smart device. The cartridge is complemented by a 3D-printed sensing gate cover plate. KRASmut, MUC1, and CD55 biomarkers either in plasma or cysts-fluid from 5 to 6 patients at a time, are multiplexed at single-molecule LOI in 1.5 h. The pancreatic cancer precursors are classified via a machine-learning analysis resulting in at least 96% diagnostic-sensitivity and 100% diagnostic-specificity. This preliminary study opens the way to POC liquid-biopsy-based early diagnosis of pancreatic-cancer precursors in plasma
CXCR6 marks a novel subset of T-bet(lo)Eomes(hi) natural killer cells residing in human liver
This work was funded by a Wellcome Trust Investigator Award to MKM funding KS and LP, MRC Career Development Award to CD, MRC Clinical Research Training Fellowship to DP, Wellcome Trust Henry Dale Fellowship to VM
Changes in Cytokine Levels and NK Cell Activation Associated with Influenza
Several studies have highlighted the important role played by murine natural killer (NK) cells in the control of influenza infection. However, human NK cell responses in acute influenza infection, including infection with the 2009 pandemic H1N1 influenza virus, are poorly documented. Here, we examined changes in NK cell phenotype and function and plasma cytokine levels associated with influenza infection and vaccination. We show that absolute numbers of peripheral blood NK cells, and particularly those of CD56bright NK cells, decreased upon acute influenza infection while this NK cell subset expanded following intramuscular influenza vaccination. NK cells exposed to influenza antigens were activated, with higher proportions of NK cells expressing CD69 in study subjects infected with seasonal influenza strains. Vaccination led to increased levels of CD25+ NK cells, and notably CD56bright CD25+ NK cells, whereas decreased amounts of this subset were present in the peripheral blood of influenza infected individuals, and predominantly in study subjects infected with the 2009 pandemic H1N1 influenza virus. Finally, acute influenza infection was associated with low plasma concentrations of inflammatory cytokines, including IFN-γ, MIP-1β, IL-2 and IL-15, and high levels of the anti-inflammatory cytokines IL-10 and IL-1ra. Altogether, these data suggest a role for the CD56bright NK cell subset in the response to influenza, potentially involving their recruitment to infected tissues and a local production and/or uptake of inflammatory cytokines
Mitoxantrone Induces Natural Killer Cell Maturation in Patients with Secondary Progressive Multiple Sclerosis
Mitoxantrone is one of the few drugs approved for the treatment of progressive multiple sclerosis (MS). However, the prolonged use of this potent immunosuppressive agent is limited by the appearance of severe side effects. Apart from its general cytotoxic effect, the mode of action of mitoxantrone on the immune system is poorly understood. Thus, to develop safe therapeutic approaches for patients with progressive MS, it is essential to elucidate how mitoxantrone exerts it benefits. Accordingly, we initiated a prospective single-arm open-label study with 19 secondary progressive MS patients. We investigated long-term effects of mitoxantrone on patient peripheral immune subsets using flow cytometry. While we corroborate that mitoxantrone persistently suppresses B cells in vivo, we show for the first time that treatment led to an enrichment of neutrophils and immunomodulatory CD8low T cells. Moreover, sustained mitoxantrone applications promoted not only persistent NK cell enrichment but also NK cell maturation. Importantly, this mitoxantrone-induced NK cell maturation was seen only in patients that showed a clinical response to treatment. Our data emphasize the complex immunomodulatory role of mitoxantrone, which may account for its benefit in MS. In particular, these results highlight the contribution of NK cells to mitoxantrone efficacy in progressive MS
The BARRIERS scale -- the barriers to research utilization scale: A systematic review
<p>Abstract</p> <p>Background</p> <p>A commonly recommended strategy for increasing research use in clinical practice is to identify barriers to change and then tailor interventions to overcome the identified barriers. In nursing, the BARRIERS scale has been used extensively to identify barriers to research utilization.</p> <p>Aim and objectives</p> <p>The aim of this systematic review was to examine the state of knowledge resulting from use of the BARRIERS scale and to make recommendations about future use of the scale. The following objectives were addressed: To examine how the scale has been modified, to examine its psychometric properties, to determine the main barriers (and whether they varied over time and geographic locations), and to identify associations between nurses' reported barriers and reported research use.</p> <p>Methods</p> <p>Medline (1991 to September 2009) and CINHAL (1991 to September 2009) were searched for published research, and ProQuest<sup>® </sup>digital dissertations were searched for unpublished dissertations using the BARRIERS scale. Inclusion criteria were: studies using the BARRIERS scale in its entirety and where the sample was nurses. Two authors independently assessed the study quality and extracted the data. Descriptive and inferential statistics were used.</p> <p>Results</p> <p>Sixty-three studies were included, with most using a cross-sectional design. Not one study used the scale for tailoring interventions to overcome identified barriers. The main barriers reported were related to the setting, and the presentation of research findings. Overall, identified barriers were consistent over time and across geographic locations, despite varying sample size, response rate, study setting, and assessment of study quality. Few studies reported associations between reported research use and perceptions of barriers to research utilization.</p> <p>Conclusions</p> <p>The BARRIERS scale is a nonspecific tool for identifying general barriers to research utilization. The scale is reliable as reflected in assessments of internal consistency. The validity of the scale, however, is doubtful. There is no evidence that it is a useful tool for planning implementation interventions. We recommend that no further descriptive studies using the BARRIERS scale be undertaken. Barriers need to be measured specific to the particular context of implementation and the intended evidence to be implemented.</p
Intestinal dysbiosis in preterm infants preceding necrotizing enterocolitis: a systematic review and meta-analysis
CD56negCD16+NK cells are activated mature NK cells with impaired effector function during HIV-1 infection
BACKGROUND: A subset of CD3(neg)CD56(neg)CD16(+) Natural Killer (NK) cells is highly expanded during chronic HIV-1 infection. The role of this subset in HIV-1 pathogenesis remains unclear. The lack of NK cell lineage-specific markers has complicated the study of minor NK cell subpopulations. RESULTS: Using CD7 as an additional NK cell marker, we found that CD3(neg)CD56(neg)CD16(+) cells are a heterogeneous population comprised of CD7(+) NK cells and CD7(neg) non-classical myeloid cells. CD7(+)CD56(neg)CD16(+) NK cells are significantly expanded in HIV-1 infection. CD7(+)CD56(neg)CD16(+) NK cells are mature and express KIRs, the C-type lectin-like receptors NKG2A and NKG2C, and natural cytotoxicity receptors similar to CD7(+)CD56(+)CD16(+) NK cells. CD7(+)CD56(neg) NK cells in healthy donors produced minimal IFNγ following K562 target cell or IL-12 plus IL-18 stimulation; however, they degranulated in response to K562 stimulation similar to CD7(+)CD56(+) NK cells. HIV-1 infection resulted in reduced IFNγ secretion following K562 or cytokine stimulation by both NK cell subsets compared to healthy donors. Decreased granzyme B and perforin expression and increased expression of CD107a in the absence of stimulation, particularly in HIV-1-infected subjects, suggest that CD7(+)CD56(neg)CD16(+) NK cells may have recently engaged target cells. Furthermore, CD7(+)CD56(neg)CD16(+) NK cells have significantly increased expression of CD95, a marker of NK cell activation. CONCLUSIONS: Taken together, CD7(+)CD56(neg)CD16(+) NK cells are activated, mature NK cells that may have recently engaged target cells
Long-term electrical characteristics of a poly-3-hexylthiophene water-gated thin-film transistor
Organic water-gated thin-film transistors (WG-TFTs) are of great interest in developing low-cost and high-performance biosensors. The device's sensitivity to changes in measurement conditions can impair long-term operation, and care must be taken to ensure that the WG-TFT sensor response is due to an actual biorecognition event occurring on the sensing electrode. This work aims to clarify the long-term stability of a poly-3-hexylthiophene (P3HT) WG-TFT operated intermittently over two months during 5750 measurement cycles. We have evaluated the device figures of merit (FOM), such as threshold voltage, mobility, and trap density, during the whole measurement period. Short-term changes in the FOM are mainly attributed to work function changes on the gate electrode, whereas long-term changes are consistent with an increase in the semiconductor trap density. The shift in threshold voltage and decrease in mobility are found to be linear as a function of measurement cycles and caused by electrical stress, with time immersed in water having a negligible effect on the device. The trap density-of-states estimated using the subthreshold slope is similar to earlier reported values for P3HT OFETs and exhibits a gradual increase during device use and a partial recovery after rest, indicating the formation of shorter- and longer-lived traps
Cytokines regulate the antigen-presenting characteristics of human circulating and tissue-resident intestinal ILCs
ILCs and T helper cells have been shown to exert bi-directional regulation in mice. However, how crosstalk between ILCs and CD4(+) T cells influences immune function in humans is unknown. Here we show that human intestinal ILCs co-localize with T cells in healthy and colorectal cancer tissue and display elevated HLA-DR expression in tumor and tumor-adjacent areas. Although mostly lacking co-stimulatory molecules ex vivo, intestinal and peripheral blood (PB) ILCs acquire antigen-presenting characteristics triggered by inflammasome-associated cytokines IL-1 beta and IL-18. IL-1 beta drives the expression of HLA-DR and co-stimulatory molecules on PB ILCs in an NF-kappa B-dependent manner, priming them as efficient inducers of cytomegalovirus-specific memory CD4(+) T-cell responses. This effect is strongly inhibited by the anti-inflammatory cytokine TGF-beta. Our results suggest that circulating and tissue-resident ILCs have the intrinsic capacity to respond to the immediate cytokine milieu and regulate local CD4(+) T-cell responses, with potential implications for anti-tumor immunity and inflammation. Murine ILCs can modulate T cell responses in MHCII-dependent manner. Here the authors show that human ILCs process and present antigens and induce T-cell responses upon exposure to IL-1-family cytokines; along with the article by Lehmann et al, this work elucidates how cytokines set context specificity of ILC-T cell crosstalk by regulating ILC antigen presentation.Funding Agencies|Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation; Swedish Research CouncilSwedish Research Council; Centre for Innovative Medicine; Jonasson center at the Royal Institute of Technology, Sweden; board of research at the Karolinska InstituteKarolinska Institutet; research committee at the Karolinska hospital; German Research Foundation (Deutsche Forschungsgemeinschaft)German Research Foundation (DFG) [RA 2986/1-1]; Swedish Cancer Foundation [130396, 160664, 170082]; Swedish Research CouncilSwedish Research Council [521-2013-2791]; Swedish Society for Medical Research [4-140/2014]; Swedish Foundation for Strategic ResearchSwedish Foundation for Strategic Research [FFL15-0120]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [4-1198/2016]; EMBO long-term fellowshipEuropean Molecular Biology Organization (EMBO) [ALTF 786-2013]; Karolinska InstitutetKarolinska Institutet; ERC-2013-ADG [341038]</p
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