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1.
N Engl J Med ; 386(1): 11-23, 2022 01 06.
Article in English | MEDLINE | ID: mdl-34986284

ABSTRACT

BACKGROUND: A single-group, phase 1-2 study indicated that eltrombopag improved the efficacy of standard immunosuppressive therapy that entailed horse antithymocyte globulin (ATG) plus cyclosporine in patients with severe aplastic anemia. METHODS: In this prospective, investigator-led, open-label, multicenter, randomized, phase 3 trial, we compared the efficacy and safety of horse ATG plus cyclosporine with or without eltrombopag as front-line therapy in previously untreated patients with severe aplastic anemia. The primary end point was a hematologic complete response at 3 months. RESULTS: Patients were assigned to receive immunosuppressive therapy (Group A, 101 patients) or immunosuppressive therapy plus eltrombopag (Group B, 96 patients). The percentage of patients who had a complete response at 3 months was 10% in Group A and 22% in Group B (odds ratio, 3.2; 95% confidence interval [CI], 1.3 to 7.8; P = 0.01). At 6 months, the overall response rate (the percentage of patients who had a complete or partial response) was 41% in Group A and 68% in Group B. The median times to the first response were 8.8 months (Group A) and 3.0 months (Group B). The incidence of severe adverse events was similar in the two groups. With a median follow-up of 24 months, a karyotypic abnormality that was classified as myelodysplastic syndrome developed in 1 patient (Group A) and 2 patients (Group B); event-free survival was 34% and 46%, respectively. Somatic mutations were detected in 29% (Group A) and 31% (Group Β) of the patients at baseline; these percentages increased to 66% and 55%, respectively, at 6 months, without affecting the hematologic response and 2-year outcome. CONCLUSIONS: The addition of eltrombopag to standard immunosuppressive therapy improved the rate, rapidity, and strength of hematologic response among previously untreated patients with severe aplastic anemia, without additional toxic effects. (Funded by Novartis and others; RACE ClinicalTrials.gov number, NCT02099747; EudraCT number, 2014-000363-40.).


Subject(s)
Anemia, Aplastic/therapy , Antilymphocyte Serum/therapeutic use , Benzoates/therapeutic use , Cyclosporine/therapeutic use , Hydrazines/therapeutic use , Immunosuppression Therapy , Immunosuppressive Agents/therapeutic use , Pyrazoles/therapeutic use , Adolescent , Adult , Aged , Aged, 80 and over , Anemia, Aplastic/drug therapy , Anemia, Aplastic/genetics , Antilymphocyte Serum/adverse effects , Benzoates/adverse effects , Cyclosporine/adverse effects , Drug Therapy, Combination , Female , Humans , Hydrazines/adverse effects , Immunosuppressive Agents/adverse effects , Male , Middle Aged , Progression-Free Survival , Prospective Studies , Pyrazoles/adverse effects , Receptors, Thrombopoietin/agonists , Remission Induction , Young Adult
2.
Ann Hematol ; 102(11): 2979-2988, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37668788

ABSTRACT

The objective of this analysis was to identify risk factors for thromboembolic events (TE) in patients with paroxysmal nocturnal hemoglobinuria (PNH) who were not treated with C5 inhibitors. Patients with PNH and a history of ≥ 1 TE at enrollment in the International PNH Registry (NCT01374360; registration date, January 2011) were each matched with up to 5 patients without TE. Multivariable analysis was performed with the following variables: percentage glycosylphosphatidylinositol (GPI)-negative cells, high disease activity (HDA), non-TE major adverse vascular event history, and recent anticoagulation. Of 2541 eligible patients, 57 with TE and 189 matched controls were analyzed. Multivariable analysis (odds ratio [95% CI]) identified the following factors as being associated with increased thrombotic risk: patients with no history of TE (with recent anticoagulation, 9.30 [1.20-72.27]), patients with history of TE (with recent anticoagulation, 8.91 [0.86-92.62]; without recent anticoagulation, 5.33 [0.26-109.57]), patients with ≥ 30% GPI-negative granulocytes (≥ 30% to < 50%, 4.94 [0.54-45.32]; ≥ 50%, 1.97 [0.45-8.55]), or patients with lactate dehydrogenase (LDH) ratio ≥ 1.5 × upper limit of normal (ULN) plus ≥ 2 HDA criteria (2-3 criteria, 3.18 [0.44-23.20]; ≥ 4 criteria, 3.60 [0.38-33.95]). History of TE, ≥ 30% GPI-negative granulocytes, and LDH ratio ≥ 1.5 × ULN with ≥ 2 HDA criteria are TE risk factors for patients with PNH. These findings will aid physicians by providing important clinical and laboratory risk factors that can be used to identify and manage patients with PNH who are at risk of developing TE.

3.
Acta Haematol ; 146(1): 1-13, 2023.
Article in English | MEDLINE | ID: mdl-36108594

ABSTRACT

INTRODUCTION: Complement C5 inhibitor eculizumab is the first approved treatment for paroxysmal nocturnal hemoglobinuria (PNH), a rare hematologic disorder caused by uncontrolled terminal complement activation. Approximately 50% of patients with aplastic anemia (AA) have PNH cells. Limited data are available for patients with AA-PNH taking concomitant immunosuppressive therapy (IST) and eculizumab. METHODS: Data from the International PNH Registry (NCT01374360) were used to evaluate the safety and effectiveness of eculizumab and IST in patients taking IST followed by concomitant eculizumab (IST + c-Ecu) or eculizumab followed by concomitant IST (Ecu + c-IST). RESULTS: As of January 1, 2018, 181 Registry-enrolled patients were included in the eculizumab effectiveness analyses (n = 138, IST + c-Ecu; n = 43, Ecu + c-IST); 87 additional patients received IST alone. Reductions from baseline with eculizumab were observed in the least squares mean lactate dehydrogenase ratio (IST + c-Ecu, -3.4; Ecu + c-IST, -3.5); thrombotic event incidence rates were similar between groups (IST + c-Ecu, 1.3; Ecu + c-IST, 0.7). Red blood cell transfusion rate ratios decreased from baseline for IST + c-Ecu (0.7) and increased for Ecu + c-IST (1.2); there were none for IST alone. Hematological parameters generally improved for IST + c-Ecu and IST alone, and changed minimally or worsened for Ecu + c-IST. Safety signals were generally consistent with those previously described for the respective therapies. DISCUSSION/CONCLUSION: Although some intergroup differences were seen, concomitant eculizumab and IST were safe and effective regardless of treatment sequence.


Subject(s)
Anemia, Aplastic , Hemoglobinuria, Paroxysmal , Humans , Anemia, Aplastic/drug therapy , Antibodies, Monoclonal, Humanized , Hemoglobinuria, Paroxysmal/complications , Hemoglobinuria, Paroxysmal/drug therapy , Immunosuppression Therapy , Registries
4.
Phys Chem Chem Phys ; 25(21): 14700-14710, 2023 May 31.
Article in English | MEDLINE | ID: mdl-36806848

ABSTRACT

Minimal understanding of the formation mechanism and structure of polydopamine (pDA) and its natural analogue, eumelanin, impedes the practical application of these versatile polymers and limits our knowledge of the origin of melanoma. The lack of conclusive structural evidence stems from the insolubility of these materials, which has spawned significantly diverse suggestions of pDA's structure in the literature. We discovered that pDA is soluble in certain ionic liquids. Using these ionic liquids (ILs) as solvents, we present an experimental methodology to solvate pDA, enabling us to identify pDA's chemical structure. The resolved pDA structure consists of self-assembled supramolecular aggregates that contribute to the increasing complexity of the polymer. The underlying molecular energetics of pDA solvation and a macroscopic picture of the disruption of the aggregates using IL solvents have been investigated, along with studies of the aggregation mechanism in water.

5.
Nature ; 532(7600): 480-3, 2016 Apr 28.
Article in English | MEDLINE | ID: mdl-27121841

ABSTRACT

The regulation of water content in polymeric membranes is important in a number of applications, such as reverse electrodialysis and proton-exchange fuel-cell membranes. External thermal and water management systems add both mass and size to systems, and so intrinsic mechanisms of retaining water and maintaining ionic transport in such membranes are particularly important for applications where small system size is important. For example, in proton-exchange membrane fuel cells, where water retention in the membrane is crucial for efficient transport of hydrated ions, by operating the cells at higher temperatures without external humidification, the membrane is self-humidified with water generated by electrochemical reactions. Here we report an alternative solution that does not rely on external regulation of water supply or high temperatures. Water content in hydrocarbon polymer membranes is regulated through nanometre-scale cracks ('nanocracks') in a hydrophobic surface coating. These cracks work as nanoscale valves to retard water desorption and to maintain ion conductivity in the membrane on dehumidification. Hydrocarbon fuel-cell membranes with surface nanocrack coatings operated at intermediate temperatures show improved electrochemical performance, and coated reverse-electrodialysis membranes show enhanced ionic selectivity with low bulk resistance.


Subject(s)
Membranes, Artificial , Nanotechnology , Polymers/chemistry , Water/analysis , Biomimetic Materials/chemistry , Biomimetics , Cactaceae/metabolism , Desiccation , Dialysis , Electrochemistry , Humidity , Hydrophobic and Hydrophilic Interactions , Plant Stomata/metabolism , Protons , Surface Properties , Temperature
6.
BMC Med ; 19(1): 184, 2021 08 20.
Article in English | MEDLINE | ID: mdl-34412655

ABSTRACT

BACKGROUND: Type 2 diabetes (T2D) is common and increasing in prevalence. It is possible to prevent or delay T2D using lifestyle intervention programmes. Entry to these programmes is usually determined by a measure of glycaemia in the 'intermediate' range. This paper investigated the relationship between HbA1c and future diabetes risk and determined the impact of varying thresholds to identify those at high risk of developing T2D. METHODS: We studied 4227 participants without diabetes aged ≥ 40 years recruited to the Exeter 10,000 population cohort in South West England. HbA1c was measured at study recruitment with repeat HbA1c available as part of usual care. Absolute risk of developing diabetes within 5 years, defined by HbA1c ≥ 48 mmol/mol (6.5%), according to baseline HbA1c, was assessed by a flexible parametric survival model. RESULTS: The overall absolute 5-year risk (95% CI) of developing T2D in the cohort was 4.2% (3.6, 4.8%). This rose to 7.1% (6.1, 8.2%) in the 56% (n = 2358/4224) of participants classified 'high-risk' with HbA1c ≥ 39 mmol/mol (5.7%; ADA criteria). Under IEC criteria, HbA1c ≥ 42 mmol/mol (6.0%), 22% (n = 929/4277) of the cohort was classified high-risk with 5-year risk 14.9% (12.6, 17.2%). Those with the highest HbA1c values (44-47 mmol/mol [6.2-6.4%]) had much higher 5-year risk, 26.4% (22.0, 30.5%) compared with 2.1% (1.5, 2.6%) for 39-41 mmol/mol (5.7-5.9%) and 7.0% (5.4, 8.6%) for 42-43 mmol/mol (6.0-6.1%). Changing the entry criterion to prevention programmes from 39 to 42 mmol/mol (5.7-6.0%) reduced the proportion classified high-risk by 61%, and increased the positive predictive value (PPV) from 5.8 to 12.4% with negligible impact on the negative predictive value (NPV), 99.6% to 99.1%. Increasing the threshold further, to 44 mmol/mol (6.2%), reduced those classified high-risk by 59%, and markedly increased the PPV from 12.4 to 23.2% and had little impact on the NPV (99.1% to 98.5%). CONCLUSIONS: A large proportion of people are identified as high-risk using current thresholds. Increasing the risk threshold markedly reduces the number of people that would be classified as high-risk and entered into prevention programmes, although this must be balanced against cases missed. Raising the entry threshold would allow limited intervention opportunities to be focused on those most likely to develop T2D.


Subject(s)
Diabetes Mellitus, Type 2 , Blood Glucose , Cohort Studies , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/prevention & control , England/epidemiology , Glycated Hemoglobin , Humans
7.
Nat Mater ; 19(7): 767-774, 2020 07.
Article in English | MEDLINE | ID: mdl-32152561

ABSTRACT

Biological ion channels have remarkable ion selectivity, permeability and rectification properties, but it is challenging to develop artificial analogues. Here, we report a metal-organic framework-based subnanochannel (MOFSNC) with heterogeneous structure and surface chemistry to achieve these properties. The asymmetrically structured MOFSNC can rapidly conduct K+, Na+ and Li+ in the subnanometre-to-nanometre channel direction, with conductivities up to three orders of magnitude higher than those of Ca2+ and Mg2+, equivalent to a mono/divalent ion selectivity of 103. Moreover, by varying the pH from 3 to 8 the ion selectivity can be tuned further by a factor of 102 to 104. Theoretical simulations indicate that ion-carboxyl interactions substantially reduce the energy barrier for monovalent cations to pass through the MOFSNC, and thus lead to ultrahigh ion selectivity. These findings suggest ways to develop ion selective devices for efficient ion separation, energy reservation and power generation.


Subject(s)
Metal-Organic Frameworks , Metals/chemistry , Nanostructures/chemistry , Cations, Monovalent , Electric Conductivity , Humans
8.
Blood ; 133(6): 540-549, 2019 02 07.
Article in English | MEDLINE | ID: mdl-30510079

ABSTRACT

Ravulizumab, a new complement component C5 inhibitor administered every 8 weeks, was noninferior to eculizumab administered every 2 weeks in complement-inhibitor-naive patients with paroxysmal nocturnal hemoglobinuria (PNH). This study assessed noninferiority of ravulizumab to eculizumab in clinically stable PNH patients during previous eculizumab therapy. In this phase 3, open-label, multicenter study, 195 PNH patients on labeled-dose (900 mg every 2 weeks) eculizumab for >6 months were randomly assigned 1:1 to switch to ravulizumab (n = 97) or continue eculizumab (n = 98). Primary efficacy end point was percentage change in lactate dehydrogenase (LDH) from baseline to day 183. Key secondary end points included proportion of patients with breakthrough hemolysis, change in Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue score, transfusion avoidance, and stabilized hemoglobin. In 191 patients completing 183 days of treatment, ravulizumab was noninferior to eculizumab (P inf < .0006 for all end points), including percentage change in LDH (difference, 9.21% [95% confidence interval (CI), -0.42 to 18.84], P = .058 for superiority), breakthrough hemolysis (difference, 5.1 [95% CI, -8.89 to 18.99]), change in FACIT-Fatigue score (difference, 1.47 [95% CI, -0.21 to 3.15]), transfusion avoidance (difference, 5.5 [95% CI, -4.27 to 15.68]), and stabilized hemoglobin (difference, 1.4 [95% CI, -10.41 to 13.31]). The most frequently reported adverse event was headache (26.8%, ravulizumab; 17.3%, eculizumab). No meningococcal infections or discontinuations due to adverse events occurred. Patients with PNH may be safely and effectively switched from labeled-dose eculizumab administered every 2 weeks to ravulizumab administered every 8 weeks. This trial was funded by Alexion Pharmaceuticals, Inc., and is registered at www.clinicaltrials.gov as #NCT03056040.


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Complement C5/antagonists & inhibitors , Complement Inactivating Agents/therapeutic use , Hemoglobinuria, Paroxysmal/drug therapy , Salvage Therapy , Adult , Drug Resistance, Neoplasm/drug effects , Female , Follow-Up Studies , Hemoglobinuria, Paroxysmal/immunology , Hemoglobinuria, Paroxysmal/pathology , Hemolysis/drug effects , Humans , Male , Middle Aged , Prognosis
9.
Blood ; 133(6): 530-539, 2019 02 07.
Article in English | MEDLINE | ID: mdl-30510080

ABSTRACT

Ravulizumab (ALXN1210), a new complement C5 inhibitor, provides immediate, complete, and sustained C5 inhibition. This phase 3, open-label study assessed the noninferiority of ravulizumab to eculizumab in complement inhibitor-naive adults with paroxysmal nocturnal hemoglobinuria (PNH). Patients with lactate dehydrogenase (LDH) ≥1.5 times the upper limit of normal and at least 1 PNH symptom were randomized 1:1 to receive ravulizumab or eculizumab for 183 days (N = 246). Coprimary efficacy end points were proportion of patients remaining transfusion-free and LDH normalization. Secondary end points were percent change from baseline in LDH, change from baseline in Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue score, proportion of patients with breakthrough hemolysis, stabilized hemoglobin, and change in serum free C5. Ravulizumab was noninferior to eculizumab for both coprimary and all key secondary end points (Pinf < .0001): transfusion avoidance (73.6% vs 66.1%; difference of 6.8% [95% confidence interval (CI), -4.66, 18.14]), LDH normalization (53.6% vs 49.4%; odds ratio, 1.19 [0.80, 1.77]), percent reduction in LDH (-76.8% vs -76.0%; difference [95% CI], -0.83% [-5.21, 3.56]), change in FACIT-Fatigue score (7.07 vs 6.40; difference [95% CI], 0.67 [-1.21, 2.55]), breakthrough hemolysis (4.0% vs 10.7%; difference [95% CI], -6.7% [-14.21, 0.18]), and stabilized hemoglobin (68.0% vs 64.5%; difference [95% CI], 2.9 [-8.80, 14.64]). The safety and tolerability of ravulizumab and eculizumab were similar; no meningococcal infections occurred. In conclusion, ravulizumab given every 8 weeks achieved noninferiority compared with eculizumab given every 2 weeks for all efficacy end points, with a similar safety profile. This trial was registered at www.clinicaltrials.gov as #NCT02946463.


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Complement Inactivating Agents/therapeutic use , Drug Resistance, Neoplasm/drug effects , Hemoglobinuria, Paroxysmal/drug therapy , Salvage Therapy , Adult , Female , Follow-Up Studies , Hemoglobinuria, Paroxysmal/immunology , Hemoglobinuria, Paroxysmal/pathology , Hemolysis/drug effects , Humans , Male , Middle Aged , Prognosis
10.
Haematologica ; 106(1): 230-237, 2021 01 01.
Article in English | MEDLINE | ID: mdl-31949012

ABSTRACT

Eculizumab is first-line treatment for paroxysmal nocturnal hemoglobinuria (PNH); however, approximately 11%-27% of patients may experience breakthrough hemolysis (BTH) on approved doses of eculizumab. Ravulizumab, a new long-acting C5 inhibitor with a four-times longer mean half-life than eculizumab, provides immediate, complete, and sustained C5 inhibition over 8-week dosing intervals. In two phase 3 studies, ravulizumab was noninferior to eculizumab (Pinf ≤0.0004) for the BTH endpoint; fewer patients experienced BTH with ravulizumab versus eculizumab in both studies (301 [complement inhibitor-naive patients], 4.0% vs 10.7%; 302 [patients stabilized on eculizumab at baseline], 0% vs 5.1%). In the current analysis, patient-level data were evaluated to assess causes and clinical parameters associated with incidents of BTH reported during the 26-week treatment periods in the ravulizumab phase 3 PNH studies. Of the five BTH events occurring in ravulizumab-treated patients across the studies, none were temporally associated with suboptimal C5 inhibition (free C5 ≥0.5 µg/mL); four (80.0%) were temporally associated with complement-amplifying conditions (CACs). Of the 22 events occurring in eculizumab-treated patients, eleven were temporally associated with suboptimal C5 inhibition, including three events also associated with concomitant infection. Six events were associated with CACs only. Five events were unrelated to free C5 elevation or reported CACs. These results suggest that the immediate, complete, and sustained C5 inhibition achieved through weight-based dosing of ravulizumab reduces the risk of BTH by eliminating BTH associated with suboptimal C5 inhibition in patients with PNH. Clinicaltrials.gov identifiers: Study 301, NCT02946463; Study 302, NCT03056040.


Subject(s)
Hemoglobinuria, Paroxysmal , Adult , Antibodies, Monoclonal, Humanized , Hemoglobinuria, Paroxysmal/drug therapy , Hemolysis , Humans
11.
Eur J Haematol ; 107(2): 211-218, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34060690

ABSTRACT

OBJECTIVES: A retrospective population-based study to determine the incidence and prevalence of patients with the rare blood disease paroxysmal nocturnal haemoglobinuria (PNH). METHODS: All patients were identified by flow cytometric detection of blood cells deficient in glycosylphosphatidylinositol (GPI) linked proteins at a single diagnostic reference laboratory that serves the Yorkshire based, Haematological Malignancy Research Network (HMRN) with a population of 3.8 million. RESULTS: One hundred and ninety-seven patients with detectable PNH clones at a level of >0.01% in at least two lineages of cells (neutrophils, monocytes and/or red cells) were identified over a 15-year period (2004-2018). Of these, 88% had aplastic anaemia (AA), 8% classical PNH and 3% myelodysplastic syndrome. The overall incidence rate was estimated at 0.35 cases per 100 000 people per year. This equates to 220 cases newly diagnosed in the United Kingdom each year. The overall prevalence rate was 3.81 per 100 000, this equates to an estimated 2400 prevalent cases in the UK. The overall and relative 5-year survival rates were 72% and 82.7%, respectively. CONCLUSIONS: This study showed that classical haemolytic PNH is a rare disease and represents only a small proportion overall of patients with detectable PNH cells, the majority of which have aplastic anaemia.


Subject(s)
Anemia, Aplastic/complications , Anemia, Aplastic/epidemiology , Hemoglobinuria, Paroxysmal/complications , Hemoglobinuria, Paroxysmal/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Anemia, Aplastic/diagnosis , Anemia, Aplastic/history , Biomarkers , Child , Child, Preschool , Female , Hemoglobinuria, Paroxysmal/diagnosis , Hemoglobinuria, Paroxysmal/history , History, 21st Century , Humans , Immunophenotyping , Incidence , Male , Middle Aged , Population Surveillance , Prevalence , Retrospective Studies , Syndrome , United Kingdom/epidemiology , Young Adult
12.
Eur J Haematol ; 106(3): 389-397, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33301613

ABSTRACT

Ravulizumab every 8 weeks showed non-inferiority to eculizumab every 2 weeks in a 26-week, phase 3, randomized controlled trial in adults with paroxysmal nocturnal hemoglobinuria (PNH) who were clinically stable on eculizumab (NCT03056040). We report results from the first 26 weeks of the extension period in which patients continued ravulizumab (n = 96) or switched from eculizumab to ravulizumab (n = 95). At week 52, mean (SD) lactate dehydrogenase levels increased 8.8% (29%) with ravulizumab-ravulizumab and 5.8% (27%) with eculizumab-ravulizumab from primary evaluation period baseline. During the extension period, four patients (ravulizumab-ravulizumab, n = 3; eculizumab-ravulizumab, n = 1) experienced breakthrough hemolysis, but none associated with serum free C5 ≥ 0.5 µg/mL. Mean Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue scores remained stable through week 52. During the extension period, proportions of patients avoiding transfusion remained stable (ravulizumab-ravulizumab, 86.5%; eculizumab-ravulizumab, 83.2%); 81.2% and 81.1%, respectively, had stabilized hemoglobin. All patients maintained serum free C5 levels < 0.5 µg/mL. Adverse events were generally similar between groups, and rates were lower in the extension period. Adults with PNH on stable eculizumab therapy who received ravulizumab over 52 weeks experienced durable efficacy, with consistent efficacy in patients who received eculizumab during the primary evaluation period and then switched to ravulizumab. Ravulizumab was well tolerated.


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , Complement Inactivating Agents/therapeutic use , Hemoglobinuria, Paroxysmal/drug therapy , Adult , Antibodies, Monoclonal, Humanized/administration & dosage , Antibodies, Monoclonal, Humanized/adverse effects , Blood Transfusion , Combined Modality Therapy , Complement C5/immunology , Complement C5/metabolism , Complement Inactivating Agents/administration & dosage , Complement Inactivating Agents/adverse effects , Female , Hemoglobinuria, Paroxysmal/blood , Hemoglobinuria, Paroxysmal/diagnosis , Hemolysis , Humans , Male , Molecular Targeted Therapy , Quality of Life , Retreatment , Treatment Outcome
13.
Br J Haematol ; 189(5): 954-966, 2020 06.
Article in English | MEDLINE | ID: mdl-32103498

ABSTRACT

A retrospective analysis of presentation clinical, laboratory and immunophenotypic features of 1 081 patients with paroxysmal nocturnal haemoglobinuria (PNH) clones [glycosylphosphatidylinositol (GPI)-deficient blood cells] identified at our hospital by flow cytometry over the past 25 years was undertaken. Three distinct clusters of patients were identified and significant correlations between presentation disease type and PNH clone sizes were evident. Smaller PNH clones predominate in cytopenic and myelodysplastic subtypes; large PNH clones were associated with haemolytic, thrombotic and haemolytic/thrombotic subtypes. Rare cases with an associated chronic myeloproliferative disorder had either large or small PNH clones. Cytopenia was a frequent finding, highlighting bone marrow failure as the major underlying feature associated with the detection of PNH clones in the peripheral blood. Red cell PNH clones showed significant correlations between the presence of type II (partial GPI deficiency) red cells and thrombotic disease. Haemolytic PNH was associated with type III (complete GPI deficiency) red cell populations of >20%. Those with both haemolytic and thrombotic features had major type II and type III red cell populations. Distinct patterns of presentation age decade were evident for clinical subtypes with a peak incidence of haemolytic PNH in the 30-49 year age group and a biphasic age distribution for the cytopenia group.


Subject(s)
Glycosylphosphatidylinositols/deficiency , Hemoglobinuria, Paroxysmal/blood , Adolescent , Adult , Aged , Aged, 80 and over , Anemia, Aplastic/etiology , Anemia, Hemolytic/etiology , CD55 Antigens/deficiency , CD59 Antigens/deficiency , Child , Child, Preschool , Clonal Evolution , Clone Cells/pathology , Disease Progression , Female , Flow Cytometry , Hemoglobinuria, Paroxysmal/complications , Hemoglobinuria, Paroxysmal/genetics , Hemoglobinuria, Paroxysmal/pathology , Humans , Immunophenotyping , Infant , Lymphocytes/pathology , Male , Middle Aged , Myeloproliferative Disorders/etiology , Neutrophils/pathology , Receptors, Transferrin/blood , Retrospective Studies , Thrombosis/etiology , Young Adult
14.
Am J Hematol ; 95(8): 944-952, 2020 08.
Article in English | MEDLINE | ID: mdl-32311169

ABSTRACT

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare hematological disorder, characterized by complement-mediated intravascular hemolysis and thrombosis. The increased incidence of PNH-driven thrombosis is still poorly understood, but unlike other thrombotic disorders, is thought to largely occur through complement-mediated mechanisms. Treatment with a C5 inhibitor, eculizumab, has been shown to significantly reduce the number of thromboembolic events in these patients. Based on previously described links between changes in fibrin clot structure and thrombosis in other disorders, our aim was to investigate clot structure as a possible mechanism of thrombosis in patients with PNH and the anti-thrombotic effects of eculizumab treatment on clot structure. Clot structure, fibrinogen levels and thrombin generation were examined in plasma samples from 82 patients from the National PNH Service in Leeds, UK. Untreated PNH patients were found to have increased levels of fibrinogen and thrombin generation, with subsequent prothrombotic changes in clot structure. No link was found between increasing disease severity and fibrinogen levels, thrombin generation, clot formation or structure. However, eculizumab treated patients showed decreased fibrinogen levels, thrombin generation and clot density, with increasing time spent on treatment augmenting these antithrombotic effects. These data suggest that PNH patients have a prothrombotic clot phenotype due to increased fibrinogen levels and thrombin generation, and that the antithrombotic effects of eculizumab are, in-part, due to reductions in fibrinogen and thrombin generation with downstream effects on clot structure.


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , Blood Coagulation/drug effects , Complement Inactivating Agents/therapeutic use , Hemoglobinuria, Paroxysmal/cerebrospinal fluid , Hemoglobinuria, Paroxysmal/drug therapy , Antibodies, Monoclonal, Humanized/pharmacology , Complement Inactivating Agents/pharmacology , Female , Healthy Volunteers , Hemoglobinuria, Paroxysmal/complications , Humans , Male , Phenotype
15.
Diabetologia ; 62(7): 1167-1172, 2019 07.
Article in English | MEDLINE | ID: mdl-30969375

ABSTRACT

AIMS/HYPOTHESIS: Late-onset type 1 diabetes can be difficult to identify. Measurement of endogenous insulin secretion using C-peptide provides a gold standard classification of diabetes type in longstanding diabetes that closely relates to treatment requirements. We aimed to determine the prevalence and characteristics of type 1 diabetes defined by severe endogenous insulin deficiency after age 30 and assess whether these individuals are identified and managed as having type 1 diabetes in clinical practice. METHODS: We assessed the characteristics of type 1 diabetes defined by rapid insulin requirement (within 3 years of diagnosis) and severe endogenous insulin deficiency (non-fasting C-peptide <200 pmol/l) in 583 participants with insulin-treated diabetes, diagnosed after age 30, from the Diabetes Alliance for Research in England (DARE) population cohort. We compared characteristics with participants with retained endogenous insulin secretion (>600 pmol/l) and 220 participants with severe insulin deficiency who were diagnosed under age 30. RESULTS: Twenty-one per cent of participants with insulin-treated diabetes who were diagnosed after age 30 met the study criteria for type 1 diabetes. Of these participants, 38% did not receive insulin at diagnosis, of whom 47% self-reported type 2 diabetes. Rapid insulin requirement was highly predictive of severe endogenous insulin deficiency: 85% required insulin within 1 year of diagnosis, and 47% of all those initially treated without insulin who progressed to insulin treatment within 3 years of diagnosis had severe endogenous insulin deficiency. Participants with late-onset type 1 diabetes defined by development of severe insulin deficiency had similar clinical characteristics to those with young-onset type 1 diabetes. However, those with later onset type 1 diabetes had a modestly lower type 1 diabetes genetic risk score (0.268 vs 0.279; p < 0.001 [expected type 2 diabetes population median, 0.231]), a higher islet autoantibody prevalence (GAD-, islet antigen 2 [IA2]- or zinc transporter protein 8 [ZnT8]-positive) of 78% at 13 years vs 62% at 26 years of diabetes duration; (p = 0.02), and were less likely to identify as having type 1 diabetes (79% vs 100%; p < 0.001) vs those with young-onset disease. CONCLUSIONS/INTERPRETATION: Type 1 diabetes diagnosed over 30 years of age, defined by severe insulin deficiency, has similar clinical and biological characteristics to that occurring at younger ages, but is frequently not identified. Clinicians should be aware that patients progressing to insulin within 3 years of diagnosis have a high likelihood of type 1 diabetes, regardless of initial diagnosis.


Subject(s)
Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 2/drug therapy , Insulin/therapeutic use , Adult , Aged , Autoantibodies/metabolism , C-Peptide/metabolism , Humans , Insulin/deficiency , Middle Aged
16.
Australas Psychiatry ; 27(2): 192-194, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30663325

ABSTRACT

OBJECTIVE: This paper outlines the current status of the Royal Australian and New Zealand College of Psychiatrists' (RANZCP) Continuing Professional Development (CPD) programme, its main drivers and influences, and outlines potential future changes. CONCLUSIONS: The three features that appear to be essential for an effective CPD programme are the presence of high internal motivation for CPD participation, membership valuing workplace learning, and to ensure that the content for learning remains largely work-focused. The need to incorporate best learning evidence has witnessed the international trend to include peer, reflective and interactive learning tasks into the CPD programme. For this latter change to be successful, members need to be informed about the value of these new and different learning methodologies.


Subject(s)
Competency-Based Education , Education, Medical, Continuing/methods , Program Development/standards , Psychiatry/education , Australia , Education, Medical, Continuing/trends , Humans , New Zealand
17.
Diabetologia ; 61(1): 66-74, 2018 01.
Article in English | MEDLINE | ID: mdl-28983693

ABSTRACT

AIMS/HYPOTHESIS: The aim of this study was to determine whether random non-fasting C-peptide (rCP) measurement can be used to assess hypoglycaemia risk in insulin-treated type 2 diabetes. METHODS: We compared continuous glucose monitoring-assessed SD of blood glucose and hypoglycaemia duration in 17 patients with insulin-treated type 2 diabetes and severe insulin deficiency (rCP < 200 pmol/l) and 17 matched insulin-treated control patients with type 2 diabetes but who had preserved endogenous insulin (rCP > 600 pmol/l). We then assessed the relationship between rCP and questionnaire-based measures of hypoglycaemia in 256 patients with insulin-treated type 2 diabetes and a comparison group of 209 individuals with type 1 diabetes. RESULTS: Continuous glucose monitoring (CGM)-assessed glucose variability and hypoglycaemia was greater in individuals with rCP < 200 pmol/l despite similar mean glucose. In those with low vs high C-peptide, SD of glucose was 4.2 (95% CI 3.7, 4.6) vs 3.0 (2.6, 3.4) mmol/l (p < 0.001). In the low-C-peptide vs high-C-peptide group, the proportion of individuals experiencing sustained hypoglycaemia ≤ 4 mmol/l was 94% vs 41% (p < 0.001), the mean rate of hypoglycaemia was 5.5 (4.4, 6.7) vs 2.1 (1.4, 2.9) episodes per person per week (p = 0.004) and the mean duration was 630 (619, 643) vs 223 (216, 230) min per person per week (p = 0.01). Hypoglycaemia ≤ 3 mmol/l was infrequent in individuals with preserved C-peptide (1.8 [1.2, 2.6] episodes per person per week vs 0.4 [0.1, 0.8] episodes per person per week for low vs high C-peptide, p = 0.04) and only occurred at night. In a population-based cohort with insulin-treated type 2 diabetes, self-reported hypoglycaemia was twice as frequent in those with rCP < 200 pmol/l (OR 2.0, p < 0.001) and the rate of episodes resulting in loss of consciousness or seizure was five times higher (OR 5.0, p = 0.001). The relationship between self-reported hypoglycaemia and C-peptide was similar in individuals with type 1 and type 2 diabetes. CONCLUSIONS/INTERPRETATION: Low rCP is associated with increased glucose variability and hypoglycaemia in patients with insulin-treated type 2 diabetes and represents a practical, stable and inexpensive biomarker for assessment of hypoglycaemia risk.


Subject(s)
C-Peptide/metabolism , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/metabolism , Hypoglycemia/drug therapy , Hypoglycemia/metabolism , Insulin/therapeutic use , Aged , Blood Glucose/drug effects , Blood Glucose Self-Monitoring , C-Peptide/blood , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 1/metabolism , Diabetes Mellitus, Type 2/blood , Female , Humans , Hypoglycemia/blood , Hypoglycemic Agents/therapeutic use , Male
18.
N Engl J Med ; 373(11): 1032-9, 2015 Sep 10.
Article in English | MEDLINE | ID: mdl-26352814

ABSTRACT

BACKGROUND: Eculizumab, a humanized monoclonal antibody against complement protein C5 that inhibits terminal complement activation, has been shown to prevent complications of paroxysmal nocturnal hemoglobinuria (PNH) and improve quality of life and overall survival, but data on the use of eculizumab in women during pregnancy are scarce. METHODS: We designed a questionnaire to solicit data on pregnancies in women with PNH and sent it to the members of the International PNH Interest Group and to the physicians participating in the International PNH Registry. We assessed the safety and efficacy of eculizumab in pregnant patients with PNH by examining the birth and developmental records of the children born and adverse events in the mothers. RESULTS: Of the 94 questionnaires that were sent out, 75 were returned, representing a response rate of 80%. Data on 75 pregnancies in 61 women with PNH were evaluated. There were no maternal deaths and three fetal deaths (4%). Six miscarriages (8%) occurred during the first trimester. Requirements for transfusion of red cells increased during pregnancy, from a mean of 0.14 units per month in the 6 months before pregnancy to 0.92 units per month during pregnancy. Platelet transfusions were given in 16 pregnancies. In 54% of pregnancies that progressed past the first trimester, the dose or the frequency of use of eculizumab had to be increased. Low-molecular-weight heparin was used in 88% of the pregnancies. Ten hemorrhagic events and 2 thrombotic events were documented; both thrombotic events occurred during the postpartum period. A total of 22 births (29%) were premature. Twenty cord-blood samples were examined for the presence of eculizumab; the drug was detected in 7 of the samples. A total of 25 babies were breast-fed, and in 10 of these cases, breast milk was examined for the presence of eculizumab; the drug was not detected in any of the 10 breast-milk samples. CONCLUSIONS: Eculizumab provided benefit for women with PNH during pregnancy, as evidenced by a high rate of fetal survival and a low rate of maternal complications. (ClinicalTrials.gov number, NCT01374360.).


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , Complement C5/antagonists & inhibitors , Hemoglobinuria, Paroxysmal/drug therapy , Pregnancy Complications, Hematologic/drug therapy , Adolescent , Adult , Antibodies, Monoclonal, Humanized/adverse effects , Female , Fetal Death , Humans , Pregnancy , Premature Birth/epidemiology , Registries , Surveys and Questionnaires , Young Adult
19.
Nat Mater ; 16(3): 342-348, 2017 03.
Article in English | MEDLINE | ID: mdl-27918565

ABSTRACT

The fabrication of oriented, crystalline films of metal-organic frameworks (MOFs) is a critical step toward their application to advanced technologies such as optics, microelectronics, microfluidics and sensing. However, the direct synthesis of MOF films with controlled crystalline orientation remains a significant challenge. Here we report a one-step approach, carried out under mild conditions, that exploits heteroepitaxial growth for the rapid fabrication of oriented polycrystalline MOF films on the centimetre scale. Our methodology employs crystalline copper hydroxide as a substrate and yields MOF films with oriented pore channels on scales that primarily depend on the dimensions of the substrate. To demonstrate that an anisotropic crystalline morphology can translate to a functional property, we assembled a centimetre-scale MOF film in the presence of a dye and showed that the optical response could be switched 'ON' or 'OFF' by simply rotating the film.


Subject(s)
Metal-Organic Frameworks/chemistry , Anisotropy , Inorganic Chemicals/chemistry , Models, Molecular , Molecular Conformation , Nanotubes/chemistry , Porosity
20.
Haematologica ; 103(1): 9-17, 2018 01.
Article in English | MEDLINE | ID: mdl-29246924

ABSTRACT

Paroxysmal nocturnal hemoglobinuria is a rare acquired hematologic disorder, the most serious complication of which is thrombosis. The increased incidence of thrombosis in paroxysmal nocturnal hemoglobinuria is still poorly understood, but unlike many other thrombotic disorders, predominantly involves complement-mediated mechanisms. This review article discusses the different factors that contribute to the increased risk of thrombosis in paroxysmal nocturnal hemoglobinuria. Paroxysmal nocturnal hemoglobinuria leads to a complex and multifaceted prothrombotic state due to the pathological effects of platelet activation, intravascular hemolysis and neutrophil/monocyte activation. Platelet and endothelial microparticles as well as oxidative stress may play a role. Impaired fibrinolysis has also been observed and may be caused by several mechanisms involving interactions between complement activation, coagulation and fibrinolysis. While many factors may affect thrombosis in paroxysmal nocturnal hemoglobinuria, the relative contribution of each mechanism that has been implicated is difficult to quantify. Further studies, including novel in vivo and in vitro thrombosis models, are required in order to define the role of the individual mechanisms contributing to thrombosis, impaired fibrinolysis and clarify other complement-driven prothrombotic mechanisms in paroxysmal nocturnal hemoglobinuria.


Subject(s)
Blood Coagulation , Hemoglobinuria, Paroxysmal/blood , Hemoglobinuria, Paroxysmal/etiology , Animals , Biomarkers , Blood Platelets/metabolism , Cell-Derived Microparticles/metabolism , Disease Models, Animal , Endothelium, Vascular/metabolism , Hematopoietic Stem Cells/metabolism , Hematopoietic Stem Cells/pathology , Hemoglobins/metabolism , Hemoglobinuria, Paroxysmal/complications , Hemoglobinuria, Paroxysmal/diagnosis , Humans , Phenotype , Platelet Activation , Reactive Oxygen Species , Thrombosis/blood , Thrombosis/etiology
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