479 research outputs found
Home mechanical ventilatio:the Dutch approach
In the Netherlands we have an unique organisation of only 4 centres being responsible for all patients who need Home Mechanical ventilation(HMV). Nationwide criteria for referral and initiation of HMV are stated in our national guideline and recently a unique national learning management system (LMS) for all caregivers and professionals was developed. A nationwide multi-centric research program is running and every centre is participating. In this paper we provide information about the evolution of HMV in the Netherlands during the last 30 years, including details about the number of patients, different diagnose groups, residence and the type of ventilators
GATA2 haploinsufficient patients lack innate lymphoid cells that arise after hematopoietic cell transplantation.
Innate lymphoid cells (ILC) are important barrier tissue immune regulators. They play a pivotal role in early non-specific protection against infiltrating pathogens, regulation of epithelial integrity, suppression of pro-inflammatory immune responses and shaping the intestinal microbiota. GATA2 haploinsufficiency causes an immune disorder that is characterized by bone marrow failure and (near) absence of monocytes, dendritic cells, B cells and natural killer (NK) cells. T cells develop normally, albeit at lower numbers. Here, we describe the absence of ILCs and their progenitors in blood and bone marrow of two patients with GATA2 haploinsufficiency and show that all subsets of ILCs appear after allogeneic hematopoietic stem cell transplantation, irrespective of the preparative conditioning regimen. Our data indicate that GATA2 is involved in the development of hematopoietic precursor cells (HPC) towards the ILC lineage
External ureteric stent versus internal double J stent in kidney transplantation:a retrospective analysis on the incidence of urological complications and urinary tract infections
INTRODUCTION: Urologic complications (UCs) and urinary tract infections (UTIs) are common after kidney transplantation. Intraoperative stent placement at the vesicoureteric anastomosis reduces UC risk, but increases UTI risk.METHODS: In 2014 our stenting protocol changed from external ureteric stent (ES) to internal double J stent (DJ). We retrospectively studied the occurrence of UCs and UTIs in relation to ES or DJ in 697 kidney recipients.METHODS: An ES was used in 403 patients (57.8%), in 294 (42.2%) a DJ. ES was removed 7-12 days and DJ 3-4 weeks post-operative. Induction immunosuppression was the same in both groups. Primary outcomes at 6 months follow-up were UC (urinary leakage/ureter stenosis) and UTI; they were related to stenting procedure and clinical and transplant characteristics. The incidence of UCs was similar for ES (8.4%) and DJ (6.8%), p=0.389. ES use was a significant risk factor for UTI (OR 1.69 (1.15-2.50), p=0.008). Post-transplant hospitalization was significantly shorter in the DJ group. Despite more acute rejection episodes with ES (ES/DJ: 16.4%/6.1%, p<0.001), no clinical relevant differences in graft outcomes existed.DISCUSSION: A DJ is, compared to ES, associated with a lower incidence of UTIs and comparable occurrence of UCs and is therefore the preferred technique for stenting the vesicoureteric anastomosis.</p
Accelerated Immunodeficiency by Anti-CCR5 Treatment in HIV Infection
In 50% of progressing HIV-1 patients, CXCR4-tropic (X4) virus emerges late in infection, often overtaking CCR5-tropic (R5) virus as the dominant viral strain. This “phenotypic switch” is strongly associated with rapidly declining CD4+ T cell counts and AIDS onset, yet its causes remain unknown. Here, we analyze a mathematical model for the mechanism of X4 emergence in late-stage HIV infection and use this analysis to evaluate the utility of a promising new class of antiretroviral drugs—CCR5 inhibitors—in dual R5, X4 infection. The model shows that the R5-to-X4 switch occurs as CD4+ T cell activation levels increase above a threshold and as CD4+ T cell counts decrease below a threshold during late-stage HIV infection. Importantly, the model also shows that highly active antiretroviral therapy (HAART) can inhibit X4 emergence but that monotherapy with CCR5 blockers can accelerate X4 onset and immunodeficiency if X4 infection of memory CD4+ T cells occurs at a high rate. Fortunately, when CXCR4 blockers or HAART are used in conjunction with CCR5 blockers, this risk of accelerated immunodeficiency is eliminated. The results suggest that CCR5 blockers will be more effective when used in combination with CXCR4 blockers and caution against CCR5 blockers in the absence of an effective HAART regimen or during HAART failure
Accelerated in vivo proliferation of memory phenotype CD4+ T-cells in human HIV-1 infection irrespective of viral chemokine co-receptor tropism.
CD4(+) T-cell loss is the hallmark of HIV-1 infection. CD4 counts fall more rapidly in advanced disease when CCR5-tropic viral strains tend to be replaced by X4-tropic viruses. We hypothesized: (i) that the early dominance of CCR5-tropic viruses results from faster turnover rates of CCR5(+) cells, and (ii) that X4-tropic strains exert greater pathogenicity by preferentially increasing turnover rates within the CXCR4(+) compartment. To test these hypotheses we measured in vivo turnover rates of CD4(+) T-cell subpopulations sorted by chemokine receptor expression, using in vivo deuterium-glucose labeling. Deuterium enrichment was modeled to derive in vivo proliferation (p) and disappearance (d*) rates which were related to viral tropism data. 13 healthy controls and 13 treatment-naive HIV-1-infected subjects (CD4 143-569 cells/ul) participated. CCR5-expression defined a CD4(+) subpopulation of predominantly CD45R0(+) memory cells with accelerated in vivo proliferation (p = 2.50 vs 1.60%/d, CCR5(+) vs CCR5(-); healthy controls; P<0.01). Conversely, CXCR4 expression defined CD4(+) T-cells (predominantly CD45RA(+) naive cells) with low turnover rates. The dominant effect of HIV infection was accelerated turnover of CCR5(+)CD45R0(+)CD4(+) memory T-cells (p = 5.16 vs 2.50%/d, HIV vs controls; P<0.05), naïve cells being relatively unaffected. Similar patterns were observed whether the dominant circulating HIV-1 strain was R5-tropic (n = 9) or X4-tropic (n = 4). Although numbers were small, X4-tropic viruses did not appear to specifically drive turnover of CXCR4-expressing cells (p = 0.54 vs 0.72 vs 0.44%/d in control, R5-tropic, and X4-tropic groups respectively). Our data are most consistent with models in which CD4(+) T-cell loss is primarily driven by non-specific immune activation
Alpha-particle-induced complex chromosome exchanges transmitted through extra-thymic lymphopoiesis in vitro show evidence of emerging genomic instability
Human exposure to high-linear energy transfer α-particles includes environmental (e.g. radon gas and its decay progeny), medical (e.g. radiopharmaceuticals) and occupational (nuclear industry) sources. The associated health risks of α-particle exposure for lung cancer are well documented however the risk estimates for leukaemia remain uncertain. To further our understanding of α-particle effects in target cells for leukaemogenesis and also to seek general markers of individual exposure to α-particles, this study assessed the transmission of chromosomal damage initially-induced in human haemopoietic stem and progenitor cells after exposure to high-LET α-particles. Cells surviving exposure were differentiated into mature T-cells by extra-thymic T-cell differentiation in vitro. Multiplex fluorescence in situ hybridisation (M-FISH) analysis of naïve T-cell populations showed the occurrence of stable (clonal) complex chromosome aberrations consistent with those that are characteristically induced in spherical cells by the traversal of a single α-particle track. Additionally, complex chromosome exchanges were observed in the progeny of irradiated mature T-cell populations. In addition to this, newly arising de novo chromosome aberrations were detected in cells which possessed clonal markers of α-particle exposure and also in cells which did not show any evidence of previous exposure, suggesting ongoing genomic instability in these populations. Our findings support the usefulness and reliability of employing complex chromosome exchanges as indicators of past or ongoing exposure to high-LET radiation and demonstrate the potential applicability to evaluate health risks associated with α-particle exposure.This work was supported by the Department of Health, UK. Contract RRX95 (RMA NSDTG)
From policy to practice: exploring practitioners' perspectives on social enterprise policy claims
Cyberspace, Blockchain, Governance:How Technology Implies Normative Power and Regulation
Technologies and their inherent design choices create normative structures that affect governance. This chapter aims to illustrate how blockchain technology in particular introduces new norms into a legal framework. We first analyze the different forms of governance by distinguishing between old and new governance. With a view to code that functions as legal norms, Blockchain technology is particularly suited to create governance structures and mechanisms. However, one needs to be aware of the norms that are implicitly introduced into the legal system by a specific blockchain technology. We look at the blockchain technology that underlies cryptocurrencies such as Bitcoin. This blockchain introduces a decentralized, transparent, cryptographically locked and thus immutable shared ledger. In summary, these design choices have normative powers over the user and over user interaction. If this is indeed the case, then regulators have to actively assess newly introduced digital ledger technology and other technologies for their effect on the normative and legal system.</p
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