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1.
Haematologica ; 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38235519

RESUMO

This multicentre, phase II study of the Australian Lymphoma and Leukaemia Group (ALLG) and the Asian Myeloma Network (AMN) investigated fixed-duration (18-month) treatment with carfilzomib (K), thalidomide (T), and dexamethasone (d; KTd) in patients with relapsed and/or refractory multiple myeloma and 1-3 prior lines of therapy. Patients received induction with up to twelve 28-day cycles of K [20mg/m2 IV cycle 1 day 1 and 2, 56mg/m2 (36mg/m2 for patients ≥75 years) from day 8 onwards), T 100mg PO nocte and weekly dexamethasone 40mg (20mg for patients ≥75 years). During maintenance T was omitted, while K continued on days 1,2,15,16 with fortnightly dexamethasone. The primary endpoint was progression free survival (PFS). Secondary endpoints were overall response rate, overall survival (OS), duration of response, safety, and tolerability. Ninety-three patients (median age 66.3 years (41.9 - 84.5)) were enrolled with a median follow-up of 26.4 (1.6 - 54.6) months. The median PFS was 22.3 months (95% CI 15.7 - 25.6) with a 46.3% (95% CI 35.1 - 52.8) 2-year PFS. Median OS was not reached and was 73.8% (95% CI 62.9 - 81.9) at 2 years. The overall response rate was 88% (≥ VGPR 73%). There was no difference in the depth of response, PFS or OS comparing Asian and Non-Asian cohorts (p=0.61). The safety profile for KTd was consistent with each individual drug. KTd is well tolerated and effective in patients with RRMM irrespective of Asian or non-Asian ethnicity and provides an alternative option particularly where use of KRd is limited by access, cost, or renal impairment.

2.
J Natl Cancer Inst ; 115(10): 1204-1212, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37697664

RESUMO

BACKGROUND: Research indicates that Black cancer patients have higher rates of COVID-19 hospitalization than their White counterparts. However, the extent to which chronic diseases contribute to racial disparities remains uncertain. We aimed to quantify the effect of chronic diseases on racial disparity in COVID-19-associated hospitalization among cancer patients. METHODS: We linked Louisiana Tumor Registry's data with statewide COVID-19 data and hospital in-patient discharge data to identify patients diagnosed with cancer in 2015-2019 who tested positive for COVID-19 in 2020 and those with COVID-19-associated hospitalization. Multivariable logistic regression and mediation methods based on linear structural equations were employed to assess the effects of the number of chronic diseases (0, 1-2, ≥3) and individual chronic diseases. RESULTS: Of 6381 cancer patients who tested positive for COVID-19, 31.6% were non-Hispanic Black cancer patients. Compared with non-Hispanic White cancer patients, non-Hispanic Black cancer patients had a higher prevalence of chronic diseases (79.5% vs 66.0%) and higher COVID-19-associated hospitalization (27.2% vs 17.2%). The odds of COVID-19-associated hospitalization were 80% higher for non-Hispanic Black cancer patients than non-Hispanic White cancer patients (odds ratio = 1.80, 95% confidence interval = 1.59 to 2.04). After adjusting for age, sex, insurance, poverty, obesity, and cancer type, number of chronic diseases explained 37.8% of the racial disparity in COVID-19-associated hospitalization, and hypertension, diabetes, and chronic renal disease were the top 3 chronic diseases explaining 9.6%, 8.9%, and 7.3% of the racial disparity, respectively. CONCLUSION: Chronic diseases played a substantial role in the racial disparity in COVID-19-associated hospitalization among cancer patients, especially hypertension, diabetes, and renal disease. Understanding and addressing the root causes are crucial for targeted interventions, policies, and health-care strategies to reduce racial disparity.


Assuntos
Negro ou Afro-Americano , COVID-19 , Doença Crônica , Hospitalização , Neoplasias , Brancos , Humanos , Negro ou Afro-Americano/estatística & dados numéricos , Doença Crônica/epidemiologia , Doença Crônica/etnologia , Doença Crônica/terapia , COVID-19/epidemiologia , COVID-19/etnologia , COVID-19/terapia , Diabetes Mellitus/epidemiologia , Hospitalização/estatística & dados numéricos , Hipertensão/complicações , Hipertensão/epidemiologia , Neoplasias/epidemiologia , Neoplasias/etnologia , Neoplasias/terapia , Fatores Raciais , Estudos Retrospectivos , Estados Unidos/epidemiologia , Brancos/estatística & dados numéricos
3.
Res Pract Thromb Haemost ; 7(5): 100196, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37601024

RESUMO

Background: Restoring hemostasis in patients on oral anticoagulants presenting with major hemorrhage (MH) or before surgical intervention has changed, with the replacement of vitamin K antagonist (VKA) with direct oral anticoagulants (DOACs). Objectives: To observe the difference in urgent hemostatic management between patients on VKA and those on DOACs. Methods: A multicenter observational study evaluated the variation in laboratory testing, hemostatic management, mortality, and hospital length of stay (LOS) in patients on VKA or DOACs presenting with MH or urgent hemostatic restoration. Results: Of the 1194 patients analyzed, 783 had MH (61% VKA) and 411 required urgent hemostatic restoration before surgery (56% VKA). Compared to the international normalized ratio (97.6%), plasma DOAC levels were measured less frequently (<45%), and the time taken from admission for the coagulation sample to reach the laboratory varied widely (median, 52.3 minutes; IQR, 24.8-206.7). No significant plasma DOAC level (<50 ng/mL) was found in up to 19% of patients. There was a poor relationship between plasma DOAC level and the usage of a hemostatic agent. When compared with patients receiving VKA (96.5%) or dabigatran (93.7%), fewer patients prescribed a factor Xa inhibitor (75.5%) received a prohemostatic reversal agent. The overall 30-day mortality for MH (mean: 17.8%) and length of stay (LOS) (median: 8.7 days) was similar between VKA and DOAC patients. Conclusion: In DOAC patients, when compared to those receiving VKA, plasma DOAC levels were measured less frequently than the international normalized ratio and had a poor relationship with administering a hemostatic reversal agent. In addition, following MH, mortality and LOS were similar between VKA and DOAC patients.

4.
Sci Rep ; 13(1): 9172, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37280424

RESUMO

Thrombosis is one of the cardinal manifestations of myeloproliferative neoplasms (MPN). The mechanisms leading to a prothrombotic state in MPN are complex and remain poorly understood. Platelet mitochondria play a role in platelet activation, but their number and function have not been extensively explored in MPN to date. We observed an increased number of mitochondria in platelets from MPN patients compared with healthy donors. MPN patients had an increased proportion of dysfunctional platelet mitochondria. The fraction of platelets with depolarized mitochondria at rest was increased in essential thrombocythemia (ET) patients and the mitochondria were hypersensitive to depolarization following thrombin agonist stimulation. Live microscopy showed a stochastic process in which a higher proportion of individual ET platelets underwent mitochondrial depolarization and after a shorter agonist exposure compared to healthy donors. Depolarization was immediately followed by ballooning of the platelet membrane, which is a feature of procoagulant platelets. We also noted that the mitochondria of MPN patients were on average located nearer the platelet surface and we observed extrusion of mitochondria from the platelet surface as microparticles. These data implicate platelet mitochondria in a number of prothrombotic phenomena. Further studies are warranted to assess whether these findings correlate with clinical thrombotic events.


Assuntos
Transtornos Mieloproliferativos , Neoplasias , Trombocitemia Essencial , Trombose , Humanos , Plaquetas/metabolismo , Trombina/metabolismo , Transtornos Mieloproliferativos/metabolismo , Trombocitemia Essencial/metabolismo , Trombose/metabolismo , Ativação Plaquetária , Neoplasias/metabolismo , Mitocôndrias
5.
Methods Mol Biol ; 2663: 441-461, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37204729

RESUMO

Heparin-induced thrombocytopenia (HIT) is a well-characterized, iatrogenic complication of heparin anticoagulation with significant morbidity. In contrast, vaccine-induced immune thrombotic thrombocytopenia (VITT) is a recently recognized severe prothrombotic complication of adenoviral vaccines, including the ChAdOx1 nCoV-19 (Vaxzevria, AstraZeneca) and Ad26.COV2.S (Janssen, Johnson & Johnson) vaccines against COVID-19. The diagnosis of HIT and VITT involve laboratory testing for antiplatelet antibodies by immunoassays followed by confirmation by functional assays to detect platelet-activating antibodies. Functional assays are critical to detect pathological antibodies due to the varying sensitivity and specificity of immunoassays. This chapter presents a protocol for a novel whole blood flow cytometry-based assay to detect procoagulant platelets in healthy donor blood in response to plasma from patients suspected of HIT or VITT. A method to identify suitable healthy donors for HIT and VITT testing is also described.


Assuntos
COVID-19 , Trombocitopenia , Trombose , Vacinas , Humanos , Plaquetas , Ad26COVS1 , Vacinas contra COVID-19/efeitos adversos , ChAdOx1 nCoV-19 , Citometria de Fluxo , Trombocitopenia/induzido quimicamente , Trombocitopenia/diagnóstico , Anticorpos , Fator Plaquetário 4
6.
Semin Thromb Hemost ; 49(5): 444-452, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36706782

RESUMO

Heparin-induced thrombocytopenia (HIT) and vaccine-induced immune thrombotic thrombocytopenia (VITT) are rare, iatrogenic immune-mediated conditions with high rates of thrombosis-related morbidity and mortality. HIT is a long-recognized reaction to the administration of the common parenterally administered anticoagulant heparin (or its derivatives), while VITT is a new, distinct syndrome occurring in response to adenovirus-based vaccines against coronavirus disease 2019 and potentially other types of vaccines. A feature of both HIT and VITT is paradoxical thrombosis despite a characteristic low platelet count, mediated by the presence of platelet-activating antibodies to platelet factor 4. Several additional factors have also been suggested to contribute to clot formation in HIT and/or VITT, including monocytes, tissue factor, microparticles, endothelium, the formation of neutrophil extracellular traps, complement, procoagulant platelets, and vaccine components. In this review, we discuss the literature to date regarding mechanisms contributing to thrombosis in both HIT and VITT and explore the pathophysiological similarities and differences between the two conditions.


Assuntos
COVID-19 , Púrpura Trombocitopênica Idiopática , Trombocitopenia , Trombose , Vacinas , Humanos , Fator Plaquetário 4
7.
Intern Med J ; 53(1): 68-73, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-32786035

RESUMO

BACKGROUND: Low molecular weight heparins (LMWH) are used extensively for prophylaxis and treatment of venous thromboembolism (VTE), bridging therapy for warfarin and standard of care in cancer-associated VTE (CA-VTE). Tinzaparin has the highest molecular weight of all LMWH and relies least on renal clearance to Cockcroft-Gault creatinine clearance (CrCl) of 20 mL/min. Previous pharmacological studies have demonstrated safety and effectiveness in elderly patients. Prospective clinical trials have confirmed these findings to CrCl 20 mL/min and in CA-VTE. We describe the pilot program developed at Concord Repatriation General Hospital for tinzaparin. AIMS: We aim to confirm the deliverability of tinzaparin in patients with renal insufficiency. METHODS: Twenty patients were established on tinzaparin as therapeutic anticoagulation with CrCl or CKD-EPI estimated glomerular filtration rate (eGFR) 20-50 mL/min with an indication for anticoagulation. Tinzaparin was given as a subcutaneous injection at 175 units/kg as a single daily dose, rounded to the nearest vial size. Tinzaparin anti-Xa levels were tested at Days 2, 7 and 14 (±1 day) and transition to oral anticoagulants were allowed at clinician discretion. RESULTS: No accumulation of tinzaparin was seen into Day 14. Two patients required dose-adjustment, five patients had bleeding complications (two major, three minor) and four patients died during follow-up, all attributable to patients' comorbidities. CrCl and body surface area-standardised CrCl were significantly correlated with tinzaparin anti-Xa level only on Day 2, and this effect was lost when patients with CrCl >50 mL/min were excluded. Data from our cohort confirm the deliverability of therapeutic tinzaparin in patients with CrCl or CKD-EPI eGFR 20-50 mL/min. Bleeding and death outcomes were also comparable to other trials using tinzaparin in CA-VTE. CONCLUSION: For patients with renal insufficiency, tinzaparin represents an attractive alternative anticoagulant with once-daily administration in a range of potential indications.


Assuntos
Insuficiência Renal Crônica , Insuficiência Renal , Tromboembolia Venosa , Humanos , Idoso , Tinzaparina/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Projetos Piloto , Tromboembolia Venosa/prevenção & controle , Estudos Prospectivos , Anticoagulantes/efeitos adversos , Insuficiência Renal/induzido quimicamente , Insuficiência Renal Crônica/tratamento farmacológico
8.
Front Epidemiol ; 3: 1108452, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38455937

RESUMO

Background: Precancerous cervical lesion (PCL) is common in working-age and minority women. In Louisiana, 98% of PCL cases were diagnosed at age 18-65 with over 90% of them being human papillomavirus (HPV)-related. PCL women represent those who may be immunocompromised from the precancerous condition and thus more vulnerable to SARS-CoV-2. Most studies evaluating racial disparities for COVID-19 infection have only used data prior to vaccine availability. This study assessed disparities by race/ethnicity and socioeconomic status (SES) in COVID-19 infections among working-age PCL women for pre- and post-COVID-19 vaccine availability. Methods: Louisiana women aged 18-65 with PCL diagnosed in 2009-2021 were linked with the Louisiana statewide COVID-19 database to identify those with positive COVID-19 test. Race/ethnicity was categorized as non-Hispanic white (NHW), non-Hispanic black (NHB), Hispanic, and others. The census tract SES quintiles were created based on American Community Survey estimates. Logistic regression was employed to assess the racial/ethnic and SES differences in COVID-19 infections. Results: Of 14,669 eligible PCL women, 30% were tested COVID-19 positive. NHB had the highest percentage of COVID-19 infection (34.6%), followed by NHW (27.7%). The infection percentage was inversely proportional to SES, with 32.9% for women having the lowest SES and 26.8% for those with the highest SES. NHB women and those with lower SES had higher COVID-19 infection than their counterparts with an aOR of 1.37 (95% CI 1.25-1.49) and 1.21 (95% CI 1.07-1.37), respectively. In the pre-vaccine period, NHB and Hispanic women had higher odds of infection than NHW women. However, after the vaccine was implemented, the significant racial/ethnic and SES differences in COVID-19 infections still existed in PCL women residing in non-Greater New Orleans area. Conclusions: There are substantial variations in racial/ethnic and SES disparities in COVID-19 infections among working-age women with PCL, even after vaccine implementation. It is imperative to provide public health interventions and resources to reduce this unequal burden for this vulnerable population.

9.
J Thromb Haemost ; 20(12): 2896-2908, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36107495

RESUMO

BACKGROUND: Vaccine-induced thrombotic thrombocytopenia (VITT) is a rare complication of adenovirus-based vaccines aimed to prevent and minimize COVID-19 and related pathophysiology. OBJECTIVES: To describe patterns of testing for anti-platelet factor 4 (PF4) antibodies using various ELISA assays in a large Australian cohort and comparative functional platelet activation assays in a subset. PATIENTS/METHODS: Asserachrom HPIA IgG ELISA was performed in 1284 patients over a period of 12 months, supplemented in select cohorts by comparative ELISA using three other methods (n = 78-179), three different functional assays (flow cytometry, serotonin release assay, and/or Multiplate; n = 476), and rapid immunological chemiluminescence anti-PF4 assay (n = 460), in a multicenter study. RESULTS: For first episode presentations, 190/1284 (14.8%) ELISA tests were positive. Conversely, most (445/460; 96.7%) chemiluminescence anti-PF4 test results were negative. All functional assays showed associations of higher median ELISA optical density with functional positivity and with high rates of ELISA positivity (64.0% to 85.2%). Data also identified functional positivity in 14.8%-36.0% of ELISA negative samples, suggesting false negative VITT by HPIA IgG ELISA in upward of one third of assessable cases. CONCLUSION: To our knowledge, this is the largest multicenter evaluation of anti-PF4 testing for investigation of VITT. Discrepancies in test results (ELISA vs. ELISA or ELISA vs. functional assay) in some patients highlighted limitations in relying on single methods (ELISA and functional) for PF4 antibody detection in VITT, and also highlights the variability in phenotypic test presentation and pathomechanism of VITT.


Assuntos
COVID-19 , Trombocitopenia , Trombose , Vacinas , Humanos , Fator Plaquetário 4 , Heparina/efeitos adversos , Austrália , Trombocitopenia/induzido quimicamente , Trombocitopenia/diagnóstico , Trombose/diagnóstico , Fatores Imunológicos/efeitos adversos , Imunoglobulina G
10.
Arterioscler Thromb Vasc Biol ; 42(8): 960-972, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35708029

RESUMO

BACKGROUND: Thrombin (via PAR [protease-activated receptor]-1 and PAR-4) and ADP (via P2Y12 receptors) are potent endogenous platelet activators implicated in the development of cardiovascular disease. We aimed to assess whether platelet pathways alter with aging. METHODS: We characterized platelet activity in community-dwelling volunteers (n=174) in the following age groups: (1) 20 to 30 (young); (2) 40 to 55 (middle-aged); (3) ≥70 years (elderly). Platelet activity was assessed by aggregometry; flow cytometry (surface markers [P-selectin: alpha granule release, CD63: dense granule release, PAC-1: measure of conformationally active GPIIb/IIIa at the fibrinogen binding site]) measured under basal conditions and after agonist stimulation [ADP, thrombin, PAR-1 agonist or PAR-4 agonist]); receptor cleavage and quantification; fluorometry; calcium flux; ELISA. RESULTS: The elderly had higher basal platelet activation than the young, evidenced by increased expression of P-selectin, CD63, and PAC-1, which correlated with increasing inflammation (IL [interleukin]-1ß/IL-6). The elderly demonstrated higher P2Y12 receptor density, with greater ADP-induced platelet aggregation (P<0.05). However, elderly subjects were resistant to thrombin, achieving less activation in response to thrombin (higher EC50) and to selective stimulation of both PAR-1 and PAR-4, with higher basal PAR-1/PAR-4 cleavage and less inducible PAR-1/PAR-4 cleavage (all P<0.05). Thrombin resistance was attributable to a combination of reduced thrombin orienting receptor GPIbα (glycoprotein Ibα), reduced secondary ADP contribution to thrombin-mediated activation, and blunted calcium flux. D-Dimer, a marker of in situ thrombin generation, correlated with platelet activation in the circulation, ex vivo thrombin resistance, and circulating inflammatory mediators (TNF [tumor necrosis factor]-α/IL-6). CONCLUSIONS: Aging is associated with a distinctive platelet phenotype of increased basal activation, ADP hyperreactivity, and thrombin resistance. In situ thrombin generation associated with systemic inflammation may be novel target to prevent cardiovascular disease in the elderly.


Assuntos
Doenças Cardiovasculares , Receptor PAR-1 , Difosfato de Adenosina/metabolismo , Difosfato de Adenosina/farmacologia , Idoso , Plaquetas/metabolismo , Cálcio/metabolismo , Doenças Cardiovasculares/metabolismo , Humanos , Inflamação/metabolismo , Interleucina-6/metabolismo , Selectina-P/metabolismo , Fenótipo , Ativação Plaquetária , Agregação Plaquetária , Receptor PAR-1/metabolismo , Receptores de Trombina/metabolismo , Trombina/metabolismo
11.
Intern Med J ; 52(5): 717-723, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35446471

RESUMO

Vaccine-induced thrombotic thrombocytopenia (VITT) is a rare, but serious, syndrome characterised by thrombocytopenia, thrombosis, a markedly raised D-dimer and the presence of anti-platelet factor-4 (PF4) antibodies following COVID-19 adenovirus vector vaccination. VITT occurs at a rate of approximately 2 per 100 000 first-dose vaccinations and appears exceedingly rare following second doses. Our current understanding of VITT pathogenesis is based on the observations that patients with VITT have antibodies that bind to PF4 and have the ability to form immune complexes that induce potent platelet activation. However, the precise mechanisms that lead to pathogenic VITT antibody development remain a source of active investigation. Thrombosis in VITT can manifest in any vascular bed and affect multiple sites simultaneously. While there is a predilection for splanchnic and cerebral venous sinus thrombosis, VITT also commonly presents with deep vein thrombosis and pulmonary embolism. Pillars of management include anticoagulation with a non-heparin anticoagulant, intravenous immunoglobulin and 'rescue' therapies, such as plasma exchange for severe cases. VITT can be associated with a high mortality rate and significant morbidity, but awareness and optimal therapy have significantly improved outcomes in Australia. A number of questions remain unanswered, including why VITT is so rare, reasons for the predilection for thrombosis in unusual sites, how long pathological antibodies persist, and the optimal duration of anticoagulation. This review will provide an overview of the presentation, diagnostic workup and management strategies for patients with VITT.


Assuntos
COVID-19 , Trombocitopenia , Trombose , Vacinas , Anticoagulantes/efeitos adversos , Vacinas contra COVID-19/efeitos adversos , Humanos , Fator Plaquetário 4/efeitos adversos , SARS-CoV-2 , Trombocitopenia/induzido quimicamente , Trombose/induzido quimicamente , Trombose/complicações , Vacinas/efeitos adversos
12.
Blood Adv ; 6(11): 3494-3506, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35359002

RESUMO

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a severe prothrombotic complication of adenoviral vaccines, including the ChAdOx1 nCoV-19 (Vaxzevria) vaccine. The putative mechanism involves formation of pathological anti-platelet factor 4 (PF4) antibodies that activate platelets via the low-affinity immunoglobulin G receptor FcγRIIa to drive thrombosis and thrombocytopenia. Functional assays are important for VITT diagnosis, as not all detectable anti-PF4 antibodies are pathogenic, and immunoassays have varying sensitivity. Combination of ligand binding of G protein-coupled receptors (protease-activated receptor-1) and immunoreceptor tyrosine-based activation motif-linked receptors (FcγRIIa) synergistically induce procoagulant platelet formation, which supports thrombin generation. Here, we describe a flow cytometry-based procoagulant platelet assay using cell death marker GSAO and P-selectin to diagnose VITT by exposing donor whole blood to patient plasma in the presence of a protease-activated receptor-1 agonist. Consecutive patients triaged for confirmatory functional VITT testing after screening using PF4/heparin ELISA were evaluated. In a development cohort of 47 patients with suspected VITT, plasma from ELISA-positive patients (n = 23), but not healthy donors (n = 32) or individuals exposed to the ChAdOx1 nCov-19 vaccine without VITT (n = 24), significantly increased the procoagulant platelet response. In a validation cohort of 99 VITT patients identified according to clinicopathologic adjudication, procoagulant flow cytometry identified 93% of VITT cases, including ELISA-negative and serotonin release assay-negative patients. The in vitro effect of intravenous immunoglobulin (IVIg) and fondaparinux trended with the clinical response seen in patients. Induction of FcγRIIa-dependent procoagulant response by patient plasma, suppressible by heparin and IVIg, is highly indicative of VITT, resulting in a sensitive and specific assay that has been adopted as part of a national diagnostic algorithm to identify vaccinated patients with platelet-activating antibodies.


Assuntos
Púrpura Trombocitopênica Idiopática , Trombocitopenia , Trombose , ChAdOx1 nCoV-19 , Citometria de Fluxo , Heparina/uso terapêutico , Humanos , Imunoglobulinas Intravenosas/efeitos adversos , Fator Plaquetário 4 , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Receptores Ativados por Proteinase/uso terapêutico , Trombocitopenia/diagnóstico , Trombose/tratamento farmacológico
13.
Platelets ; 33(8): 1139-1145, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-35316151

RESUMO

The use of mean platelet diameter (MPD) to classify inherited thrombocytopenia (IT) has been demonstrated in several studies. Alternatively, the mean platelet volume (MPV) may be used, but in macrothrombocytopenia this may not be available. We hypothesized that platelet forward scatter (FSC) measurements using flow cytometry may be used for the size-based classification of IT. The study aimed to assess the ability of platelet FSC to measure platelet size and whether it could be used as an alternative to the MPD or MPV.Blood samples were obtained from individuals undergoing investigation for inherited platelet function disorders (IPFD, n = 40) or platelet number disorders (IPND, n = 46). A hematology analyzer was used to obtain MPV and platelet counts, flow cytometry to measure platelet FSC and ImageJ software to measure MPD from stained blood smears. The International Society of Thrombosis and Hemostasis (ISTH) Bleeding Assessment Tool (BAT) was used to calculate bleeding scores.Twenty-nine(63%) of IPND patients had an MPV that could not be reported. A significant correlation to platelet FSC was found to the MPD (p < .0001) and MPV (p < .0001) and an inverse correlation with platelet count (p < .0001). No significant correlation was found between FSC and bleeding history. In conclusion, platelet FSC is an alternative to MPV and may be used in macrothrombocytopenia where the MPV is not recorded.


Assuntos
Transtornos Plaquetários , Trombocitopenia , Plaquetas , Citometria de Fluxo , Hemorragia , Humanos , Volume Plaquetário Médio , Contagem de Plaquetas , Trombocitopenia/diagnóstico
14.
Cancer Causes Control ; 33(1): 37-48, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34633573

RESUMO

PURPOSES: Our study aimed to examine the impact of diabetes, smoking and BMI on pancreatic cancer survival in a population-based setting by adjusting both sociodemographic and clinical factors and measuring their attributable risk. METHODS: Data on pancreatic adenocarcinoma patients diagnosed in 2011-2017 were acquired from the Louisiana Tumor Registry. Diabetes, smoking, height, and weight were abstracted from medical records and linked with Hospital Inpatient Discharge Data to enhance the completeness of the diabetes data. The Cox regression model was used to assess effect sizes of diabetes, smoking, and BMI on cancer-specific survival and survival rate. The partial population attributable risk was employed to measure the attributable risk of these risk factors. RESULTS: Of the 3,200 eligible patients, 34.6% were diabetics, 23.9% were current smokers, and 52.3% had BMI ≥ 25 kg/m2. After adjusting for sociodemographic and clinical factors, diabetic patients had an increased cancer-specific death risk of 15% (95% CI, 1.06-1.25), 36% (95% CI, 1.19-1.44) for current smokers, and 24% (95% CI, 1.00-1.54) for patients with a BMI ≥ 40 when compared to their counterparts. Diabetic current smokers had significantly lower 2- and 3-year adjusted cancer-specific survival rates, 13.1% and 10.5%, respectively. By eliminating diabetes and modifiable risk factors, an estimated 16.6% (95% CI, 6.9%-25.9%) of the cancer-specific deaths could be avoided during a nine-year observational period between 2011 and 2019. CONCLUSIONS: Diabetes and smoking contributed substantially to the reduction of pancreatic cancer survival even after controlling for sociodemographic and clinical factors; however, BMI ≥ 35 was observed to increase risk of mortality among stage III-IV patients only.


Assuntos
Adenocarcinoma , Diabetes Mellitus , Neoplasias Pancreáticas , Índice de Massa Corporal , Diabetes Mellitus/epidemiologia , Humanos , Neoplasias Pancreáticas/epidemiologia , Fatores de Risco
15.
Thromb Haemost ; 122(4): 517-528, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34171934

RESUMO

OBJECTIVE: Platelets are critical in mediating both rapid responses to injury and the development and progression of coronary disease. Several studies have shown that, after prolonged exposure to agonists, they produce and release inflammatory mediators including interleukin-1ß (IL-1ß), via the classical pathway (NLRP3 inflammasome and caspase-1 cleavage to release active IL-1ß) as described for leukocytes. This study aimed to determine whether there is rapid release of IL-1ß in response to soluble platelet agonists and whether such rapid release is NLRP3- and caspase-1-dependent. METHODS AND RESULTS: Using flow cytometry to detect platelet activation (and release of α and dense granule contents) and the combination of Western blotting, enzyme-linked-immunosorbent assay, and immunogold labeling transmission electron and immunofluorescence microscopy, we identified that resting human platelets contain mature IL-1ß. Platelets release IL-1ß within minutes in response to adenosine diphosphate (ADP), collagen, and thrombin receptor agonists, but not in response to conventional NLRP3 inflammasome agonists-lipopolysaccharide and adenosine triphosphate. The rapid release of IL-1ß in response to ADP and thrombin receptor agonists was independent of caspases (including caspase-1) and NLRP3. Immature and mature IL-1ß were identified as low-abundance proteins on transmission electron microscopy of human platelets, and were localized to the platelet cytosol, open canalicular system, and the periphery of α granules. CONCLUSION: Unlike monocytes and neutrophils, human platelets are capable of rapid agonist- and time-dependent release of IL-1ß by a mechanism which is independent of caspase-1 and NLRP3.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Difosfato de Adenosina , Plaquetas/metabolismo , Caspase 1/metabolismo , Caspases , Humanos , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Receptores de Trombina
16.
Clin Colorectal Cancer ; 21(2): e62-e75, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34756680

RESUMO

BACKGROUND: The National Comprehensive Cancer Network (NCCN) guidelines have recommended tailored chemotherapy for stage III high-risk (T4 and/or N2) and low-risk (T1-T3 and N1) colon cancer since 2018. Studies have investigated the effect of relative dose intensity (RDI) of FOLFOX on stage III colon cancer survival, however, none has performed a stratified analysis by risk profiles. This study aims to identify the FOLFOX optimal RDI for high-risk and low-risk stage III colon cancer patients. METHODS: Data on 407 eligible patients, diagnosed with stage III colon cancer in 2011 who received FOLFOX, were collected by 8 population-based cancer registries. Multivariable Cox model and Fine-Gray competing risks model were employed to explore Optimal RDI defined as the lowest RDI administered without significant differences in either overall or cause-specific death. RESULTS: Among the 168 high-risk patients, the optimal RDI cut-off was 70% (HR = 1.59 with 95% CI: 0.69-3.66 in overall mortality; HR = 1.24 with 95% CI: 0.42-3.64 in cause-specific mortality when RDI < 70% vs. RDI ≥ 70%). Among the 239 low-risk patients, none of the evaluated cut-offs were associated with significant differences in risk of death between comparison groups. The lowest assessed RDI was 45%, HR = 0.80; 95% CI: 0.24 to 2.73 for overall mortality and HR = 0.53; 95% CI: 0.06 to 4.95 for cause-specific mortality, when RDI <45% versus RDI ≥45%. CONCLUSIONS: There is no significant harm on the risk of death when reducing RDI by <30% for high-risk patients. For the low-risk patients, we found that RDI as low as 45% did not significantly affect the risk of death.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias do Colo , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimioterapia Adjuvante , Neoplasias do Colo/patologia , Humanos , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos
19.
Carbon Balance Manag ; 16(1): 1, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33415575

RESUMO

BACKGROUND: With a lack of United States federal policy to address climate change, cities, the private sector, and universities have shouldered much of the work to reduce carbon dioxide (CO2) and other greenhouse gas emissions. This study aims to determine how landcover characteristics influence the amount of carbon (C) sequestered and respired via biological processes, evaluating the role of land management on the overall C budget of an urban university. Boston University published a comprehensive Climate Action Plan in 2017 with the goal of achieving C neutrality by 2040. In this study, we digitized and discretized each of Boston University's three urban campuses into landcover types, with C sequestration and respiration rates measured and scaled to provide a University-wide estimate of biogenic C fluxes within the broader context of total University emissions. RESULTS: Each of Boston University's three highly urban campuses were net sources of biogenic C to the atmosphere. While trees were estimated to sequester 0.6 ± 0.2 kg C m-2 canopy cover year-1, mulch and lawn areas in 2018 emitted C at rates of 1.7 ± 0.4 kg C m-2 year-1 and 1.4 ± 0.4 kg C m-2 year-1, respectively. C uptake by tree canopy cover, which can spatially overlap lawn and mulched landcovers, was not large enough to offset biogenic emissions. The proportion of biogenic emissions to Scope 1 anthropogenic emissions on each campus varied from 0.5% to 2%, and depended primarily on the total anthropogenic emissions on each campus. CONCLUSIONS: Our study quantifies the role of urban landcover in local C budgets, offering insights on how landscaping management strategies-such as decreasing mulch application rates and expanding tree canopy extent-can assist universities in minimizing biogenic C emissions and even potentially creating a small biogenic C sink. Although biogenic C fluxes represent a small fraction of overall anthropogenic emissions on urban university campuses, these biogenic fluxes are under active management by the university and should be included in climate action plans.

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