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1.
Cell ; 187(16): 4305-4317.e18, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-38936360

ABSTRACT

Interleukin (IL)-23 and IL-17 are well-validated therapeutic targets in autoinflammatory diseases. Antibodies targeting IL-23 and IL-17 have shown clinical efficacy but are limited by high costs, safety risks, lack of sustained efficacy, and poor patient convenience as they require parenteral administration. Here, we present designed miniproteins inhibiting IL-23R and IL-17 with antibody-like, low picomolar affinities at a fraction of the molecular size. The minibinders potently block cell signaling in vitro and are extremely stable, enabling oral administration and low-cost manufacturing. The orally administered IL-23R minibinder shows efficacy better than a clinical anti-IL-23 antibody in mouse colitis and has a favorable pharmacokinetics (PK) and biodistribution profile in rats. This work demonstrates that orally administered de novo-designed minibinders can reach a therapeutic target past the gut epithelial barrier. With high potency, gut stability, and straightforward manufacturability, de novo-designed minibinders are a promising modality for oral biologics.


Subject(s)
Colitis , Interleukin-17 , Th17 Cells , Animals , Administration, Oral , Mice , Humans , Rats , Colitis/drug therapy , Interleukin-17/metabolism , Interleukin-17/antagonists & inhibitors , Th17 Cells/immunology , Receptors, Interleukin/metabolism , Receptors, Interleukin/antagonists & inhibitors , Mice, Inbred C57BL , Male , Interleukin-23/metabolism , Interleukin-23/antagonists & inhibitors , Tissue Distribution , Female , Rats, Sprague-Dawley
2.
Immunity ; 2024 Jul 06.
Article in English | MEDLINE | ID: mdl-39013466

ABSTRACT

Lassa virus is estimated to cause thousands of human deaths per year, primarily due to spillovers from its natural host, Mastomys rodents. Efforts to create vaccines and antibody therapeutics must account for the evolutionary variability of the Lassa virus's glycoprotein complex (GPC), which mediates viral entry into cells and is the target of neutralizing antibodies. To map the evolutionary space accessible to GPC, we used pseudovirus deep mutational scanning to measure how nearly all GPC amino-acid mutations affected cell entry and antibody neutralization. Our experiments defined functional constraints throughout GPC. We quantified how GPC mutations affected neutralization with a panel of monoclonal antibodies. All antibodies tested were escaped by mutations that existed among natural Lassa virus lineages. Overall, our work describes a biosafety-level-2 method to elucidate the mutational space accessible to GPC and shows how prospective characterization of antigenic variation could aid the design of therapeutics and vaccines.

3.
Nature ; 626(7998): 271-279, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38326590

ABSTRACT

Mitochondria retain bacterial traits due to their endosymbiotic origin, but host cells do not recognize them as foreign because the organelles are sequestered. However, the regulated release of mitochondrial factors into the cytosol can trigger cell death, innate immunity and inflammation. This selective breakdown in the 2-billion-year-old endosymbiotic relationship enables mitochondria to act as intracellular signalling hubs. Mitochondrial signals include proteins, nucleic acids, phospholipids, metabolites and reactive oxygen species, which have many modes of release from mitochondria, and of decoding in the cytosol and nucleus. Because these mitochondrial signals probably contribute to the homeostatic role of inflammation, dysregulation of these processes may lead to autoimmune and inflammatory diseases. A potential reason for the increased incidence of these diseases may be changes in mitochondrial function and signalling in response to such recent phenomena as obesity, dietary changes and other environmental factors. Focusing on the mixed heritage of mitochondria therefore leads to predictions for future insights, research paths and therapeutic opportunities. Thus, whereas mitochondria can be considered 'the enemy within' the cell, evolution has used this strained relationship in intriguing ways, with increasing evidence pointing to the recent failure of endosymbiosis being critical for the pathogenesis of inflammatory diseases.


Subject(s)
Inflammation , Mitochondria , Models, Biological , Symbiosis , Humans , Autoimmune Diseases/etiology , Autoimmune Diseases/metabolism , Autoimmune Diseases/pathology , Diet/adverse effects , Homeostasis , Inflammation/etiology , Inflammation/metabolism , Inflammation/pathology , Mitochondria/metabolism , Mitochondria/pathology , Mitochondria/physiology , Mitochondrial Proteins/metabolism , Nucleic Acids/metabolism , Obesity/complications , Obesity/metabolism , Obesity/pathology , Phospholipids/metabolism , Reactive Oxygen Species/metabolism , Symbiosis/physiology , Animals
4.
Nature ; 627(8004): 501-504, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38509276

ABSTRACT

Stellar chemical compositions can be altered by ingestion of planetary material1,2 and/or planet formation, which removes refractory material from the protostellar disk3,4. These 'planet signatures' appear as correlations between elemental abundance differences and the dust condensation temperature3,5,6. Detecting these planet signatures, however, is challenging owing to unknown occurrence rates, small amplitudes and heterogeneous star samples with large differences in stellar ages7,8. Therefore, stars born together (that is, co-natal) with identical compositions can facilitate the detection of planet signatures. Although previous spectroscopic studies have been limited to a small number of binary stars9-13, the Gaia satellite14 provides opportunities for detecting stellar chemical signatures of planets among co-moving pairs of stars confirmed to be co-natal15,16. Here we report high-precision chemical abundances for a homogeneous sample of ninety-one co-natal pairs of stars with a well defined selection function and identify at least seven instances of planetary ingestion, corresponding to an occurrence rate of eight per cent. An independent Bayesian indicator is deployed, which can effectively disentangle the planet signatures from other factors, such as random abundance variation and atomic diffusion17. Our study provides evidence of planet signatures and facilitates a deeper understanding of the star-planet-chemistry connection by providing observational constraints on the mechanisms of planet engulfment, formation and evolution.

5.
Circulation ; 150(6): 451-465, 2024 Aug 06.
Article in English | MEDLINE | ID: mdl-38682338

ABSTRACT

BACKGROUND: Most organs are maintained lifelong by resident stem/progenitor cells. During development and regeneration, lineage-specific stem/progenitor cells can contribute to the growth or maintenance of different organs, whereas fully differentiated mature cells have less regenerative potential. However, it is unclear whether vascular endothelial cells (ECs) are also replenished by stem/progenitor cells with EC-repopulating potential residing in blood vessels. It has been reported recently that some EC populations possess higher clonal proliferative potential and vessel-forming capacity compared with mature ECs. Nevertheless, a marker to identify vascular clonal repopulating ECs (CRECs) in murine and human individuals is lacking, and, hence, the mechanism for the proliferative, self-renewal, and vessel-forming potential of CRECs is elusive. METHODS: We analyzed colony-forming, self-renewal, and vessel-forming potential of ABCG2 (ATP binding cassette subfamily G member 2)-expressing ECs in human umbilical vessels. To study the contribution of Abcg2-expressing ECs to vessel development and regeneration, we developed Abcg2CreErt2;ROSA TdTomato mice and performed lineage tracing during mouse development and during tissue regeneration after myocardial infarction injury. RNA sequencing and chromatin methylation chromatin immunoprecipitation followed by sequencing were conducted to study the gene regulation in Abcg2-expressing ECs. RESULTS: In human and mouse vessels, ECs with higher ABCG2 expression (ABCECs) possess higher clonal proliferative potential and in vivo vessel-forming potential compared with mature ECs. These cells could clonally contribute to vessel formation in primary and secondary recipients after transplantation. These features of ABCECs meet the criteria of CRECs. Results from lineage tracing experiments confirm that Abcg2-expressing CRECs (AbcCRECs) contribute to arteries, veins, and capillaries in cardiac tissue development and vascular tissue regeneration after myocardial infarction. Transcriptome and epigenetic analyses reveal that a gene expression signature involved in angiogenesis and vessel development is enriched in AbcCRECs. In addition, various angiogenic genes, such as Notch2 and Hey2, are bivalently modified by trimethylation at the 4th and 27th lysine residue of histone H3 (H3K4me3 and H3K27me3) in AbcCRECs. CONCLUSIONS: These results are the first to establish that a single prospective marker identifies CRECs in mice and human individuals, which holds promise to provide new cell therapies for repair of damaged vessels in patients with endothelial dysfunction.


Subject(s)
ATP Binding Cassette Transporter, Subfamily G, Member 2 , Animals , Humans , Mice , ATP Binding Cassette Transporter, Subfamily G, Member 2/genetics , ATP Binding Cassette Transporter, Subfamily G, Member 2/metabolism , Endothelial Cells/metabolism , Endothelial Cells/cytology , Neovascularization, Physiologic , Cell Proliferation , Myocardial Infarction/metabolism , Myocardial Infarction/pathology , Myocardial Infarction/genetics , Myocardial Infarction/therapy , Regeneration , Human Umbilical Vein Endothelial Cells/metabolism , Mice, Transgenic , Blood Vessels/metabolism , Blood Vessels/cytology , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Cell Lineage
6.
J Mol Cell Cardiol ; 191: 12-22, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38643934

ABSTRACT

Doxorubicin (DOX) is a widely used chemotherapeutic agent that can cause serious cardiotoxic side effects, leading to heart failure (HF). Impaired mitochondrial function is thought to be key factor driving progression into HF. We have previously shown in a rat model of DOX-HF that heart failure with reduced ejection fraction correlates with mitochondrial loss and dysfunction. Adenosine monophosphate-dependent kinase (AMPK) is a cellular energy sensor, regulating mitochondrial biogenesis and energy metabolism, including fatty acid oxidation. We hypothesised that AMPK activation could restore mitochondrial function and therefore be a novel cardioprotective strategy for the prevention of DOX-HF. Consequently, we set out to assess whether 5-aminoimidazole-4-carboxamide 1-ß-D-ribofuranoside (AICAR), an activator of AMPK, could prevent cardiac functional decline in this chronic intravenous rat model of DOX-HF. In line with our hypothesis, AICAR improved cardiac systolic function. AICAR furthermore improved cardiac mitochondrial fatty acid oxidation, independent of mitochondrial number, and in the absence of observable AMPK-activation. In addition, we found that AICAR prevented loss of myocardial mass. RNAseq analysis showed that this may be driven by normalisation of pathways associated with ribosome function and protein synthesis, which are impaired in DOX-treated rat hearts. AICAR furthermore prevented dyslipidemia and excessive body-weight loss in DOX-treated rats, which may contribute to preservation of myocardial mass. Though it is unclear whether AICAR exerted its cardioprotective effect through cardiac or extra-cardiac AMPK-activation or via an AMPK-independent effect, these results show promise for the use of AICAR as a cardioprotective agent in DOX-HF to both preserve cardiac function and mass.


Subject(s)
AMP-Activated Protein Kinases , Aminoimidazole Carboxamide , Cardiotonic Agents , Doxorubicin , Heart Failure , Ribonucleotides , Animals , Doxorubicin/adverse effects , Aminoimidazole Carboxamide/analogs & derivatives , Aminoimidazole Carboxamide/pharmacology , Heart Failure/chemically induced , Heart Failure/prevention & control , Heart Failure/metabolism , Heart Failure/pathology , Heart Failure/drug therapy , Ribonucleotides/pharmacology , Male , Cardiotonic Agents/pharmacology , Rats , AMP-Activated Protein Kinases/metabolism , Mitochondria, Heart/metabolism , Mitochondria, Heart/drug effects , Myocardium/metabolism , Myocardium/pathology , Fatty Acids/metabolism , Disease Models, Animal
7.
J Physiol ; 602(6): 1211-1225, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38381050

ABSTRACT

Gestational hypoxia adversely affects uterine artery function, increasing complications. However, an effective therapy remains unidentified. Here, we show in rodent uterine arteries that hypoxic pregnancy promotes hypertrophic remodelling, increases constrictor reactivity via protein kinase C signalling, and triggers compensatory dilatation via nitric oxide-dependent mechanisms and stimulation of large conductance Ca2+ -activated K+ -channels. Maternal in vivo oral treatment with the mitochondria-targeted antioxidant MitoQ in hypoxic pregnancy normalises uterine artery reactivity and prevents vascular remodelling. From days 6-20 of gestation (term ∼22 days), female Wistar rats were randomly assigned to normoxic or hypoxic (13-14% O2 ) pregnancy ± daily maternal MitoQ treatment (500 µm in drinking water). At 20 days of gestation, maternal, placental and fetal tissue was frozen to determine MitoQ uptake. The uterine arteries were harvested and, in one segment, constrictor and dilator reactivity was determined by wire myography. Another segment was fixed for unbiased stereological analysis of vessel morphology. Maternal administration of MitoQ in both normoxic and hypoxic pregnancy crossed the placenta and was present in all tissues analysed. Hypoxia increased uterine artery constrictor responses to norepinephrine, angiotensin II and the protein kinase C activator, phorbol 12,13-dibutyrate. Hypoxia enhanced dilator reactivity to sodium nitroprusside, the large conductance Ca2+ -activated K+ -channel activator NS1619 and ACh via increased nitric oxide-dependent mechanisms. Uterine arteries from hypoxic pregnancy showed increased wall thickness and MitoQ treatment in hypoxic pregnancy prevented all effects on uterine artery reactivity and remodelling. The data support mitochondria-targeted therapy against adverse changes in uterine artery structure and function in high-risk pregnancy. KEY POINTS: Dysfunction and remodelling of the uterine artery are strongly implicated in many pregnancy complications, including advanced maternal age, maternal hypertension of pregnancy, maternal obesity, gestational diabetes and pregnancy at high altitude. Such complications not only have immediate adverse effects on the growth of the fetus, but also they can also increase the risk of cardiovascular disease in the mother and offspring. Despite this, there is a significant unmet clinical need for therapeutics that treat uterine artery vascular dysfunction in adverse pregnancy. Here, we show in a rodent model of gestational hypoxia that in vivo oral treatment of the mitochondria-targeted antioxidant MitoQ protects against uterine artery vascular dysfunction and remodelling, supporting the use of mitochondria-targeted therapy against adverse changes in uterine artery structure and function in high-risk pregnancy.


Subject(s)
Placenta , Uterine Artery , Humans , Rats , Animals , Pregnancy , Female , Placenta/metabolism , Uterine Artery/physiology , Antioxidants/pharmacology , Antioxidants/metabolism , Rodentia , Nitric Oxide/metabolism , Rats, Wistar , Hypoxia , Protein Kinase C/metabolism , Mitochondria/metabolism
8.
Br J Haematol ; 204(5): 1660-1671, 2024 May.
Article in English | MEDLINE | ID: mdl-38419589

ABSTRACT

The supply of blood components and products in sufficient quantities is key to any effective health care system. This report describes the challenges faced by the English blood service, NHS Blood and Transplant (NHSBT), towards the end of the COVID-19 pandemic, which in October 2022 led to an Amber Alert being declared to hospitals indicating an impending blood shortage. The impact on the hospital transfusion services and clinical users is explained. The actions taken by NHSBT to mitigate the blood supply challenges and ensure equity of transfusion support for hospitals in England including revisions to the national blood shortage plans are described. This report focuses on the collaboration and communication between NHSBT, NHS England (NHSE), Department of Health and Social Care (DHSC), National Blood Transfusion Committee (NBTC), National Transfusion Laboratory Managers Advisory Group for NBTC (NTLM), National Transfusion Practitioners Network, the medical Royal Colleges and clinical colleagues across the NHS.


Subject(s)
Blood Donors , Blood Transfusion , COVID-19 , SARS-CoV-2 , Humans , England , COVID-19/epidemiology , Blood Transfusion/statistics & numerical data , Blood Donors/supply & distribution , Blood Banks/supply & distribution , State Medicine/organization & administration , Pandemics
9.
Basic Res Cardiol ; 119(4): 691-697, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38864895

ABSTRACT

The mitochondrial metabolite succinate is a key driver of ischemia/reperfusion injury (IRI). Targeting succinate metabolism by inhibiting succinate dehydrogenase (SDH) upon reperfusion using malonate is an effective therapeutic strategy to achieve cardioprotection in the short term (< 24 h reperfusion) in mouse and pig in vivo myocardial infarction (MI) models. We aimed to assess whether inhibiting IRI with malonate given upon reperfusion could prevent post-MI heart failure (HF) assessed after 28 days. Male C57BL/6 J mice were subjected to 30 min left anterior coronary artery (LAD) occlusion, before reperfusion for 28 days. Malonate or without-malonate control was infused as a single dose upon reperfusion. Cardiac function was assessed by echocardiography and fibrosis by Masson's trichrome staining. Reperfusion without malonate significantly reduced ejection fraction (~ 47%), fractional shortening (~ 23%) and elevated collagen deposition 28 days post-MI. Malonate, administered as a single infusion (16 mg/kg/min for 10 min) upon reperfusion, gave a significant cardioprotective effect, with ejection fraction (~ 60%) and fractional shortening (~ 30%) preserved and less collagen deposition. Using an acidified malonate formulation, to enhance its uptake into cardiomyocytes via the monocarboxylate transporter 1, both 1.6 and 16 mg/kg/min 10 min infusion led to robust long-term cardioprotection with preserved ejection fraction (> 60%) and fractional shortening (~ 30%), as well as significantly less collagen deposition than control hearts. Malonate administration upon reperfusion prevents post-MI HF. Acidification of malonate enables lower doses of malonate to also achieve long-term cardioprotection post-MI. Therefore, the administration of acidified malonate upon reperfusion is a promising therapeutic strategy to prevent IRI and post-MI HF.


Subject(s)
Disease Models, Animal , Heart Failure , Malonates , Mice, Inbred C57BL , Myocardial Infarction , Myocardial Reperfusion Injury , Animals , Malonates/pharmacology , Male , Myocardial Infarction/metabolism , Myocardial Infarction/pathology , Myocardial Infarction/prevention & control , Myocardial Infarction/physiopathology , Myocardial Reperfusion Injury/prevention & control , Myocardial Reperfusion Injury/metabolism , Myocardial Reperfusion Injury/pathology , Myocardial Reperfusion Injury/physiopathology , Heart Failure/prevention & control , Heart Failure/metabolism , Heart Failure/drug therapy , Heart Failure/physiopathology , Heart Failure/etiology , Mice , Myocardium/metabolism , Myocardium/pathology , Ventricular Function, Left/drug effects , Fibrosis , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/pathology , Time Factors
10.
J Vasc Surg ; 2024 May 17.
Article in English | MEDLINE | ID: mdl-38763455

ABSTRACT

OBJECTIVE: Postoperative day-one discharge is used as a quality-of-care indicator after carotid revascularization. This study identifies predictors of prolonged length of stay (pLOS), defined as a postprocedural LOS of >1 day, after elective carotid revascularization. METHODS: Patients undergoing carotid endarterectomy (CEA), transcarotid artery revascularization (TCAR), and transfemoral carotid artery stenting (TFCAS) in the Vascular Quality Initiative between 2016 and 2022 were included in this analysis. Multivariable logistic regression analysis was used to identify predictors of pLOS, defined as a postprocedural LOS of >1 day, after each procedure. RESULTS: A total of 118,625 elective cases were included. pLOS was observed in nearly 23.2% of patients undergoing carotid revascularization. Major adverse events, including neurological, cardiac, infectious, and bleeding complications, occurred in 5.2% of patients and were the most significant contributor to pLOS after the three procedures. Age, female sex, non-White race, insurance status, high comorbidity index, prior ipsilateral CEA, non-ambulatory status, symptomatic presentation, surgeries occurring on Friday, and postoperative hypo- or hypertension were significantly associated with pLOS across all three procedures. For CEA, additional predictors included contralateral carotid artery occlusion, preoperative use of dual antiplatelets and anticoagulation, low physician volume (<11 cases/year), and drain use. For TCAR, preoperative anticoagulation use, low physician case volume (<6 cases/year), no protamine use, and post-stent dilatation intraoperatively were associated with pLOS. One-year analysis showed a significant association between pLOS and increased mortality for all three procedures; CEA (hazard ratio [HR],1.64; 95% confidence interval [CI], 1.49-1.82), TCAR (HR,1.56; 95% CI, 1.35-1.80), and TFCAS (HR, 1.33; 95%CI, 1.08-1.64) (all P < .05). CONCLUSIONS: A postoperative LOS of more than 1 day is not uncommon after carotid revascularization. Procedure-related complications are the most common drivers of pLOS. Identifying patients who are risk for pLOS highlights quality improvement strategies that can optimize short and 1-year outcomes of patients undergoing carotid revascularization.

11.
Transfusion ; 64(7): 1217-1222, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38767410

ABSTRACT

BACKGROUND: Drugs such as daratumumab (Darzalex, anti-CD38) and Hu5F9-G4 (magrolimab, anti-CD47) may interfere with red blood cell compatibility testing as CD38 and CD47 are expressed on red blood cells. STUDY DESIGN AND METHODS: A survey of AABB member transfusion services was undertaken to understand their experiences of managing patients taking therapeutic monoclonal antibodies that are known to interfere with blood grouping and compatibility testing. RESULTS: The survey was distributed to the contact person at US-based AABB member transfusion services. The response rate was 27%. 172 of 240 (72%) indicated they had difficulties in performing compatibility testing in patients taking daratumumab and 66 of 91 (73%) reported difficulties in performing compatibility testing in patients taking magrolimab. Actions taken to provide compatible blood for these patients included referral of all samples to a reference center, blood group pheno/genotyping the patient in advance of starting the drug, treating reagent cells with 0.2 M dithiothreitol and using K-negative red cell units for patients taking daratumumab, and Gamma-clone (Immucor) anti-IgG for indirect antiglobulin testing for patients taking magrolimab. Lack of communication from clinical services about drug treatment was identified as a concern. CONCLUSION: The results of the survey demonstrate that transfusion services are having challenges with the transfusion management of patients taking therapeutic monoclonal antibodies, and further education is needed.


Subject(s)
ADP-ribosyl Cyclase 1 , Antibodies, Monoclonal, Humanized , Antibodies, Monoclonal , CD47 Antigen , Humans , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Blood Grouping and Crossmatching , Erythrocytes/immunology , Blood Group Incompatibility , Blood Transfusion , Surveys and Questionnaires , Membrane Glycoproteins
12.
Transfusion ; 64(7): 1243-1253, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38752406

ABSTRACT

BACKGROUND: Fetal and neonatal exposure to lead is associated with irreversible adverse effects on neural development. There is no reliable threshold for lead effect, so limiting exposure is recommended. A significant correlation has been reported between post-transfusion blood lead level (BLL) in infants and lead levels in transfused RBC units. We measured levels of lead, mercury, and cadmium, in Canadian donor blood to investigate if concerning levels for neonatal transfusion exist. STUDY DESIGN AND METHODS: Whole blood samples from blood donors (n = 2529) were shipped cold within 7 days of donation. All permanent blood donation clinics across Canada were sampled. Twelve of these permanent clinics and 8 mobile clinics with a greater potential for having higher lead or mercury levels were oversampled. Heavy metals were measured by inductively coupled plasma mass spectrometry. RESULTS: Of all donations, 2.2% (lead) and 0.4% (mercury) had levels higher than the recommended thresholds for safe neonatal transfusion. BLLs were higher in males but there was no significant difference in the blood mercury levels of males versus females. Cadmium levels were higher in females. There was a positive correlation between donor age and levels of heavy metals, with lead having the strongest correlation (r = 0.47, p < .0001). Three clinics in close proximity to two lead-producing mines were among the clinics with the highest BLLs. Significantly higher blood mercury levels were observed in coastal clinics. CONCLUSION: Our data on donor blood heavy metal levels supports considering blood transfusion as an exposure source to heavy metals and encourages informed selection of blood units for transfusion to vulnerable groups.


Subject(s)
Blood Donors , Cadmium , Lead , Mercury , Humans , Lead/blood , Female , Mercury/blood , Male , Cadmium/blood , Canada , Adult , Middle Aged , Young Adult , Adolescent , Infant, Newborn
13.
Transfusion ; 64(5): 775-783, 2024 May.
Article in English | MEDLINE | ID: mdl-38516758

ABSTRACT

BACKGROUND: Immunoglobulin (IG) therapy is widely used to treat primary and secondary immune deficiencies and as immunomodulatory agent for various disorders. There is great concern that shortages of IG may rise, potentially affecting medical treatment options. STUDY DESIGN AND METHODS: An international survey was developed to study how intravenous immunoglobulins (IVIGs) are used and managed within hospitals in case of shortages. Study data were collected and managed using REDCap electronic data capture tools hosted by the Biomedical Excellence for Safer Transfusion (BEST) Collaborative. The survey was directed to hospital pharmacists and blood bank transfusion professionals and disseminated through members of the BEST Collaborative network. RESULTS: Survey respondents from institutions in the USA, Canada, Europe, Japan, and Australia (n = 13) confirmed that the primary specialties utilizing IG are neurology, hematology, and immunology. More than 60% of respondents reported IG supply shortages, but mitigation strategies were not well developed. DISCUSSION: As IG is the leading driver in plasma demand, more studies are needed to understand current and future demand for IG from the clinical perspective. Necessity lies in establishing clinical guidance to address shortages.


Subject(s)
Immunoglobulins, Intravenous , Humans , Surveys and Questionnaires , Immunoglobulins, Intravenous/therapeutic use , Australia , Canada , Hospitals/statistics & numerical data , Japan , United States , Blood Banks/supply & distribution , Blood Banks/statistics & numerical data
14.
Transfusion ; 64(7): 1223-1232, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38769631

ABSTRACT

BACKGROUND: Blood components are costly and scarce. The Blood Stocks Management Scheme (BSMS) was established in the United Kingdom (UK) to support hospital transfusion services and national blood services through collection, analysis, and monthly feedback of data on blood component inventory and wastage management. There is a growing evidence base on how best to deliver feedback for quality improvement. We assessed the quality and utility of the monthly BSMS component reports. METHODS: We assessed the content of BSMS reports issued in March 2023 against established criteria for effective feedback. Two researchers independently rated whether criteria spanning the five domains of goal setting, data collection, feedback content, feedback display and feedback delivery were fully, partially or not met. Disagreements were resolved through discussion. We conducted an online questionnaire survey of recipients of BSMS reports during March 2023 to assess their use of reports and seek suggestions for improvement. RESULTS: Five out of 20 criteria for effective feedback were fully met. Areas for improvement included placing more emphasis in the feedback on positive change, linking data and summary messages, and including specific suggestions for action. Respondents highlighted the value of benchmarked comparisons with other hospital transfusion services. CONCLUSION: There is scope for enhancing the effectiveness and utility of BSMS feedback reports and hence reducing wastage of blood components. This methodology for evaluation of feedback could be utilized to improve other areas of transfusion practice.


Subject(s)
Blood Component Transfusion , Humans , United Kingdom , Surveys and Questionnaires , Feedback , Blood Banks/standards , Quality Improvement , Blood Transfusion/standards
15.
Transfusion ; 64(4): 638-645, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38506497

ABSTRACT

BACKGROUND: Healthcare activities significantly contribute to greenhouse gas (GHG) emissions. Blood transfusions require complex, interlinked processes to collect, manufacture, and supply. Their contribution to healthcare emissions and avenues for mitigation is unknown. STUDY DESIGN AND METHODS: We performed a life cycle assessment (LCA) for red blood cell (RBC) transfusions across England where 1.36 million units are transfused annually. We defined the process flow with seven categories: donation, transportation, manufacturing, testing, stockholding, hospital transfusion, and disposal. We used direct measurements, manufacturer data, bioengineering databases, and surveys to assess electrical power usage, embodied carbon in disposable materials and reagents, and direct emissions through transportation, refrigerant leakage, and disposal. RESULTS: The central estimate of carbon footprint per unit of RBC transfused was 7.56 kg CO2 equivalent (CO2eq). The largest contribution was from transportation (2.8 kg CO2eq, 36% of total). The second largest was from hospital transfusion processes (1.9 kg CO2eq, 26%), driven mostly by refrigeration. The third largest was donation (1.3 kg CO2eq, 17%) due to the plastic blood packs. Total emissions from RBC transfusion are ~10.3 million kg CO2eq/year. DISCUSSION: This is the first study to estimate GHG emissions attributable to RBC transfusion, quantifying the contributions of each stage of the process. Primary areas for mitigation may include electric vehicles for the blood service fleet, improving the energy efficiency of refrigeration, using renewable sources of electricity, changing the plastic of blood packs, and using methods of disposal other than incineration.


Subject(s)
Carbon Footprint , Greenhouse Effect , Humans , Animals , Blood Transfusion , Life Cycle Stages , England
16.
Bioorg Med Chem ; 104: 117712, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38593670

ABSTRACT

Glutathione-S-transferases are key to the cellular detoxification of xenobiotics and products of oxidative damage. GSTs catalyse the reaction of glutathione (GSH) with electrophiles to form stable thioether adducts. GSTK1-1 is the main GST isoform in the mitochondrial matrix, but the GSTA1-1 and GSTA4-4 isoforms are also thought to be in the mitochondria with their distribution altering in transformed cells, thus potentially providing a cancer specific target. A mitochondria-targeted version of the GST substrate 1-chloro-2,4-dinitrobenzene (CDNB), MitoCDNB, has been used to manipulate the mitochondrial GSH pool. To finesse this approach to target particular GST isoforms in the context of cancer, here we have determined the kcat/Km for the human isoforms of GSTK1-1, GSTA1-1 and GSTA4-4 with respect to GSH and CDNB. We show how the rate of the GST-catalysed reaction between GSH and CDNB analogues can be modified by both the electron withdrawing substituents, and by the position of the mitochondria-targeting triphenylphosphonium on the chlorobenzene ring to tune the activity of mitochondria-targeted substrates. These findings can now be exploited to selectively disrupt the mitochondrial GSH pools of cancer cells expressing particular GST isoforms.


Subject(s)
Glutathione Transferase , Mitochondria , Humans , Dinitrobenzenes , Glutathione , Glutathione Transferase/metabolism , Kinetics , Mitochondria/metabolism , Organophosphorus Compounds , Protein Isoforms
17.
J Peripher Nerv Syst ; 2024 Jul 07.
Article in English | MEDLINE | ID: mdl-38973168

ABSTRACT

BACKGROUND AND AIMS: The goal of this study was to define basic constituents of the adult peripheral nervous system (PNS) using intact human nerve tissues. METHODS: We combined fluorescent and chromogenic immunostaining methods, myelin-selective fluorophores, and routine histological stains to identify common cellular and noncellular elements in aldehyde-fixed nerve tissue sections. We employed Schwann cell (SC)-specific markers, such as S100ß, NGFR, Sox10, and myelin protein zero (MPZ), together with axonal, extracellular matrix (collagen IV, laminin, fibronectin), and fibroblast markers to assess the SC's relationship to myelin sheaths, axons, other cell types, and the acellular environment. RESULTS: Whereas S100ß and Sox10 revealed mature SCs in the absence of other stains, discrimination between myelinating and non-myelinating (Remak) SCs required immunodetection of NGFR along with axonal and/or myelin markers. Surprisingly, our analysis of NGFR+ profiles uncovered the existence of at least 3 different novel populations of NGFR+/S100ß- cells, herein referred to as nonglial cells, residing in the stroma and perivascular areas of all nerve compartments. An important proportion of the nerve's cellular content, including circa 30% of endoneurial cells, consisted of heterogenous S100ß negative cells that were not associated with axons. Useful markers to identify the localization and diversity of nonglial cell types across different compartments were Thy1, CD34, SMA, and Glut1, a perineurial cell marker. INTERPRETATION: Our optimized methods revealed additional detailed information to update our understanding of the complexity and spatial orientation of PNS-resident cell types in humans.

18.
BMC Psychiatry ; 24(1): 433, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38858652

ABSTRACT

BACKGROUND: Objective and quantifiable markers are crucial for developing novel therapeutics for mental disorders by 1) stratifying clinically similar patients with different underlying neurobiological deficits and 2) objectively tracking disease trajectory and treatment response. Schizophrenia is often confounded with other psychiatric disorders, especially bipolar disorder, if based on cross-sectional symptoms. Awake and sleep EEG have shown promise in identifying neurophysiological differences as biomarkers for schizophrenia. However, most previous studies, while useful, were conducted in European and American populations, had small sample sizes, and utilized varying analytic methods, limiting comprehensive analyses or generalizability to diverse human populations. Furthermore, the extent to which wake and sleep neurophysiology metrics correlate with each other and with symptom severity or cognitive impairment remains unresolved. Moreover, how these neurophysiological markers compare across psychiatric conditions is not well characterized. The utility of biomarkers in clinical trials and practice would be significantly advanced by well-powered transdiagnostic studies. The Global Research Initiative on the Neurophysiology of Schizophrenia (GRINS) project aims to address these questions through a large, multi-center cohort study involving East Asian populations. To promote transparency and reproducibility, we describe the protocol for the GRINS project. METHODS: The research procedure consists of an initial screening interview followed by three subsequent sessions: an introductory interview, an evaluation visit, and an overnight neurophysiological recording session. Data from multiple domains, including demographic and clinical characteristics, behavioral performance (cognitive tasks, motor sequence tasks), and neurophysiological metrics (both awake and sleep electroencephalography), are collected by research groups specialized in each domain. CONCLUSION: Pilot results from the GRINS project demonstrate the feasibility of this study protocol and highlight the importance of such research, as well as its potential to study a broader range of patients with psychiatric conditions. Through GRINS, we are generating a valuable dataset across multiple domains to identify neurophysiological markers of schizophrenia individually and in combination. By applying this protocol to related mental disorders often confounded with each other, we can gather information that offers insight into the neurophysiological characteristics and underlying mechanisms of these severe conditions, informing objective diagnosis, stratification for clinical research, and ultimately, the development of better-targeted treatment matching in the clinic.


Subject(s)
Electroencephalography , Schizophrenia , Adult , Female , Humans , Male , Biomarkers , Cohort Studies , Electroencephalography/methods , Neurophysiology/methods , Research Design , Schizophrenia/physiopathology , Schizophrenia/diagnosis , Sleep/physiology , Cross-Sectional Studies , Middle Aged , Aged
19.
J Chem Phys ; 161(8)2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39177086

ABSTRACT

Biological cell membranes are primarily comprised of a diverse lipid bilayer with multiple phospholipid (lipid) types, each of which is comprised of a hydrophilic headgroup and two hydrophobic hydrocarbon tails. The lipid type determines the molecular structure of head and tail groups, which can affect membrane mechanics at nanoscale and subsequently cell viability under mechanical loading. Hence, using molecular dynamics simulations, the current study investigated seven membrane phospholipids and the effect of their structural differences on physical deformation, mechanoporation damage, and mechanical failure of the membranes under tension. The inspected phospholipids showed similar yield stresses and strains, as well as pore evolution and damage, but significantly different failure strains. In general, failure occurred at a lower strain for lipids with a larger equilibrium area per lipid. The obtained results suggest that larger headgroup structure, greater degree of unsaturation, and tail-length asymmetry influenced the phospholipids' ability to pack against each other, increased the fluidity and equilibrium area per lipid of the membrane, and resulted in lower failure strain. Overall, this study provides insights on how different phospholipid structures affect membrane physical responses at the molecular level and serves as a reference for future studies of more complex membrane systems with intricate biophysical properties.


Subject(s)
Cell Membrane , Molecular Dynamics Simulation , Phospholipids , Phospholipids/chemistry , Cell Membrane/chemistry , Lipid Bilayers/chemistry , Molecular Structure
20.
Transfus Med ; 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39117599

ABSTRACT

OBJECTIVES: To report the UK experience of rolling out Transfusion Camp. BACKGROUND: Transfusion Camp is a structured education programme developed in Toronto, with the aim of reducing knowledge gaps in transfusion medicine in postgraduate trainees. It consists of didactic lectures viewed online by the participants, then interactive, locally delivered seminars. Since 2015, it has been rolled out in the United Kingdom, and is now available in four centres. Here, we report the UK experience of Transfusion Camp and outcomes. METHODS: Trainees are recruited via the training programme directors in each region. Pre- and post-course assessments are administered using the validated BEST (Biomedical Excellence for Safer Transfusion) test, with possible scores 0-20, and confidence measured on an A-E Likert scale. RESULTS: Since 2015, 130 trainees have participated in Transfusion Camp in the United Kingdom. Trainees from all specialties significantly improved their BEST-test scores after attending the course (mean score 11.6/20 before the course, compared with 14.3/20 after the course), and confidence in managing transfusion-related issues was also significantly improved. CONCLUSION: We recommend that all centres consider offering Transfusion Camp to trainees in haematology and other specialties that frequently use blood transfusions, such as anaesthesia/ICU, Internal Medicine and others.

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