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1.
Vox Sang ; 119(3): 265-271, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38141176

ABSTRACT

BACKGROUND AND OBJECTIVES: The practice regarding the selection and preparation of red blood cells (RBCs) for intrauterine transfusion (IUT) is variable reflecting historical practice and expert opinion rather than evidence-based recommendations. The aim of this survey was to assess Canadian hospital blood bank practice with respect to red cell IUT. MATERIALS AND METHODS: A survey was sent to nine hospital laboratories known to perform red cell IUT. Questions regarding component selection, processing, foetal pre-transfusion testing, transfusion administration, documentation and traceability were assessed. RESULTS: The median annual number of IUTs performed in Canada was 109 (interquartile range, 103-118). RBC selection criteria included allogeneic, Cytomegalovirus seronegative, irradiated, fresh units with most sites preferentially providing HbS negative, group O, RhD negative, Kell negative and units lacking the corresponding maternal antibody without extended matching to the maternal phenotype. Red cell processing varied with respect to target haematocrit, use of saline reconstitution (n = 4), use of an automated procedure for red cell concentration (n = 1) and incorporation of a wash step (n = 2). Foetal pre-transfusion testing uniformly included haemoglobin measurement, but additional serologic testing varied. A variety of strategies were used to link the IUT event to the neonate post-delivery, including the creation of a unique foetal blood bank identifier at three sites. CONCLUSION: This survey reviews current practice and highlights the need for standardized national guidelines regarding the selection and preparation of RBCs for IUT. This study has prompted a re-examination of priorities for RBC selection for IUT and highlighted strategies for transfusion traceability in this unique setting.


Subject(s)
Blood Transfusion, Intrauterine , Erythrocytes , Pregnancy , Female , Infant, Newborn , Humans , Blood Transfusion, Intrauterine/methods , Canada , Erythrocytes/metabolism , Blood Transfusion , Erythrocyte Transfusion/methods
2.
Vox Sang ; 118(12): 1086-1094, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37794849

ABSTRACT

BACKGROUND AND OBJECTIVES: Canadian out-of-hospital blood transfusion programmes (OHBTPs) are emerging, to improve outcomes of trauma patients by providing pre-hospital transfusion from the scene of injury, given prolonged transport times. Literature is lacking to guide its implementation. Thus, we sought to gather technical transfusion medicine (TM)-specific practices across Canadian OHBTPs. MATERIALS AND METHODS: A survey was sent to TM representatives of Canadian OHBTPs from November 2021 to March 2022. Data regarding transport, packaging, blood components and inventory management were included and reported descriptively. Only practices involving Blood on Board programme components for emergency use were included. RESULTS: OHBTPs focus on helicopter emergency medical service programmes, with some supplying fixed-wing aircraft and ground ambulances. All provide 1-3 coolers with 2 units of O RhD/Kell-negative red blood cells (RBCs) per cooler, with British Columbia trialling coolers with 2 units of pre-thawed group A plasma. Inventory exchanges are scheduled and blood components are returned to TM inventory using visual inspection and internal temperature data logger readings. Coolers are validated to storage durations ranging from 72 to 124 h. All programmes audit to manage wastage, though there is no consensus on appropriate benchmarks. All programmes have a process for documenting units issued, reconciliation after transfusion and for transfusion reaction reporting; however, training programmes vary. Common considerations included storage during extreme temperature environments, O-negative RBC stewardship, recipient notification, traceability, clinical practice guidelines co-reviewed by TM and a common audit framework. CONCLUSION: OHBTPs have many similarities throughout Canada, where harmonization may assist in further developing standards, leveraging best practice and national coordination.


Subject(s)
Transfusion Medicine , Humans , Canada , Blood Transfusion , Blood Component Transfusion , Hospitals
3.
Chem Res Toxicol ; 25(10): 2227-35, 2012 Oct 15.
Article in English | MEDLINE | ID: mdl-22931364

ABSTRACT

There is growing evidence that amorphous silica nanoparticles (SiO2-NP) can cause an inflammatory response in the lung. We studied in vitro the effects of exposing human lung submucosal cells to SiO2-NP of various sizes (10, 150, and 500 nm) for 2-24 h. Cell survival, reactive oxygen species (ROS), malondialdehyde (MDA) levels, cytokine production, inflammatory gene expression, and genotoxicity were measured after exposure of Calu-3 cells to 10SiO2-NP in the presence or absence of the flavanoid fisetin and an antioxidant enzyme catalase. The exposure of Calu-3 cells to 10SiO2-NP resulted in (1) increased cytotoxicity and cell death in a time- and concentration-dependent manner, with a lethal concentration (LC50) of 9.7 µg/mL after 24 h; (2) enhanced gene expression of interleukin (IL)-6, IL-8, and matrix metalloproteinase-9; (3) a significant correlation between increases in MDA and cytotoxicity at 18 h; (4) ROS production; (5) IL-6 and IL-8 release; and (6) up-regulation of the pro-apoptotic genes, p53 and caspase-3. Cell death and inflammatory reactions were attenuated by fisetin and catalase. We observed that 150- and 500SiO2-NP exerted no toxic effects on Calu-3 cells. In conclusion, the nanotoxicity of amorphous 10SiO2-NP on submucosal cells is associated with inflammation, the release of ROS leading to apoptosis, and decreased cell survival. The nanotoxic effects of 10SiO2-NP can be decreased by fisetin and catalase treatment, implicating oxidative stress in this injury.


Subject(s)
Cytotoxins/toxicity , Flavonoids/pharmacology , Lung/drug effects , Nanoparticles/toxicity , Silicon Dioxide/toxicity , Caspase 3/genetics , Cell Death/drug effects , Cell Line , Flavonols , Humans , Inflammation/chemically induced , Inflammation/genetics , Inflammation/prevention & control , Interleukin-6/genetics , Interleukin-8/genetics , Lung/cytology , Lung/metabolism , Malondialdehyde/metabolism , Matrix Metalloproteinase 9/genetics , Particle Size , Reactive Oxygen Species/metabolism , Up-Regulation/drug effects
4.
ACS Omega ; 4(6): 10078-10088, 2019 Jun 30.
Article in English | MEDLINE | ID: mdl-31460100

ABSTRACT

While a wide range of experimental and commercial transfection reagents are currently available, persistent problems remain regarding their suitability for continued development. These include the transfection efficiency for difficult-to-transfect cell types and the risks of decreased cell viability that may arise from any transfection that does occur. Therefore, research is now turning toward alternative molecules that improve the toxicity profile of the gene delivery vector (GDV), while maintaining the transfection efficiency. Among them, cell-penetrating peptides, such as octa-arginine, have shown significant potential as GDVs. Their pharmacokinetic and pharmacodynamic properties can be enhanced through peptidomimetic conversion, whereby a peptide is modified into a synthetic analogue that mimics its structure and/or function, but whose backbone is not solely based on α-amino acids. Using this technology, novel peptidomimetics were developed by co- and postpolymerization functionalization of substituted ethylene oxides, producing poly(ethylene glycol) (PEG)-based peptidomimetics termed "PEGtides". Specifically, a PEGtide of the poly(α-amino acid) oligo-arginine [poly(glycidylguanidine)] was assessed for its ability to complex and deliver a small interfering ribonucleic acid (siRNA) using a range of cell assays and high-content analysis. PEGtide-siRNA demonstrated significantly increased internalization and gene inhibition over 24 h in Calu-3 pulmonary epithelial cells compared to commercial controls and octa-arginine-treated samples, with no evidence of toxicity. Furthermore, PEGtide-siRNA nanocomplexes can provide significant levels of gene inhibition in "difficult-to-transfect" mouse embryonic hypothalamic (mHypo N41) cells. Overall, the usefulness of this novel PEGtide for gene delivery was clearly demonstrated, establishing it as a promising candidate for continued translational research.

5.
Expert Opin Ther Targets ; 18(6): 633-49, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24660778

ABSTRACT

INTRODUCTION: Prostate cancer is a leading cause of cancer-related death in men and current treatments offer only a modest survival benefit in advanced stages of the disease. RNA interference (RNAi) is a therapeutic option that has received great attention in recent years with the potential to treat a variety of disorders, including prostate cancer. Transcription factors are cellular proteins that can up-regulate or down-regulate the transcription of genes and offer promising therapeutic targets. AREAS COVERED: This review will focus on transcription factors that have been identified as key molecules in drug resistance, disease progression and metastases in prostate cancer, which may offer potential as therapeutic targets for RNAi in the future. EXPERT OPINION: By identifying therapeutically viable transcription factor targets in prostate cancer, it is hoped that treatment strategies using RNAi will augment the effect of current chemotherapy regimens, slow disease progression and reduce metastases in prostate cancer, resulting in disease regression.


Subject(s)
Prostatic Neoplasms/therapy , RNA Interference , Transcription Factors/physiology , Androgen Antagonists/therapeutic use , Forkhead Box Protein M1 , Forkhead Transcription Factors/physiology , Humans , Male , NF-kappa B/metabolism , Receptors, Androgen/physiology , STAT Transcription Factors/physiology , Serum Response Factor/physiology , Transcription Factor AP-1/physiology , Transcription Factors/antagonists & inhibitors , Transcription Factors/genetics
6.
Biomaterials ; 35(1): 489-99, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24138827

ABSTRACT

Progression of RNA interference-based gene silencing technologies for the treatment of disorders of the central nervous system (CNS) depends on the availability of efficient non-toxic nanocarriers. Despite advances in the field of nanotechnology undesired and non-specific interactions with different brain-cell types occur and are poorly investigated. To this end, we studied the cytotoxic and neuroinflammatory effects of widely-used transfection reagents and modified amphiphilic ß-cyclodextrins (CDs). All non-viral vectors formed positively charged nanoparticles with distinctive physicochemical properties. Differential and significant cytotoxic effects were observed among commercially available cationic vectors, whereas CDs induced limited disruptions of cellular membrane integrity and mitochondrial dehydrogenase activity. Interestingly, murine derived BV2 microglia cells and a rat striatal in vitro model of Huntington's disease (ST14A-HTT120Q) were more susceptible to toxicity than human U87 astroglioma cells. BV2 microglia presented significant increases in cytokine, toll-like receptor 2 and cyclooxygenase-2 gene expression after transfection with selected commercial vectors but not with CD.siRNA nanoparticles. Non-viral siRNA nanoparticles formulated with G6 polyamidoamine (PAMAM) also significantly increased cytokine gene expression in the brain following injections into the mouse striatum. Together our data identify modified CDs as nanosystems that enable siRNA delivery to the brain with low levels of cytotoxicity and immunological activation.


Subject(s)
Corpus Striatum/drug effects , Genetic Vectors , Inflammation/chemically induced , Microglia/drug effects , Nanoparticles/toxicity , RNA Interference , Animals , Base Sequence , Cell Line, Tumor , Humans , Mice , Microglia/cytology , RNA, Small Interfering/genetics , Rats
7.
Cytokine Growth Factor Rev ; 24(2): 91-104, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23102645

ABSTRACT

Pattern recognition receptors (PRRs) are a family of germline encoded receptors responsible for the detection of "pathogen associated molecular patterns" (PAMPs) or host derived "damage associated molecular patterns" (DAMPs) which induce innate immune signalling to generate a pro-inflammatory profile within the host. Four main classes of PRRs are recognised, Toll-like receptors (TLRs), NOD-like receptors (NLRs), RIG-like receptors (RLRs) and C-type lectin receptors (CLRs). Abnormal activation of PRRs has been implicated in various autoimmune and inflammatory conditions including rheumatoid arthritis and asthma. Recent growing evidence has implicated these PRRs as contributory elements to the pathogenesis of inflammatory bowel disease (IBD) and colitis-associated cancer (CAC). Here, the current literature which implicates PRRs in IBD and CAC is comprehensively reviewed.


Subject(s)
Inflammatory Bowel Diseases/immunology , Receptors, Pattern Recognition/immunology , Animals , Humans , Inflammatory Bowel Diseases/complications , Neoplasms/etiology , Neoplasms/immunology
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