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1.
Mol Biol Evol ; 41(2)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38314890

RESUMEN

Intraspecific functional variation is critical for adaptation to rapidly changing environments. For visual opsins, functional variation can be characterized in vitro and often reflects a species' ecological niche but is rarely considered in the context of intraspecific variation or the impact of recent environmental changes on species of cultural or commercial significance. Investigation of adaptation in postglacial lakes can provide key insight into how rapid environmental changes impact functional evolution. Here, we report evidence for molecular adaptation in vision in 2 lineages of Nearctic fishes that are deep lake specialists: ciscoes and deepwater sculpin. We found depth-related variation in the dim-light visual pigment rhodopsin that evolved convergently in these 2 lineages. In vitro characterization of spectral sensitivity of the convergent deepwater rhodopsin alleles revealed blue-shifts compared with other more widely distributed alleles. These blue-shifted rhodopsin alleles were only observed in deep clear postglacial lakes with underwater visual environments enriched in blue light. This provides evidence of remarkably rapid and convergent visual adaptation and intraspecific functional variation in rhodopsin. Intraspecific functional variation has important implications for conservation, and these fishes are of conservation concern and great cultural, commercial, and nutritional importance to Indigenous communities. We collaborated with the Saugeen Ojibway Nation to develop and test a metabarcoding approach that we show is efficient and accurate in recovering the ecological distribution of functionally relevant variation in rhodopsin. Our approach bridges experimental analyses of protein function and genetics-based tools used in large-scale surveys to better understand the ecological extent of adaptive functional variation.


Asunto(s)
Evolución Molecular , Rodopsina , Animales , Rodopsina/genética , Rodopsina/metabolismo , Peces/genética , Peces/metabolismo , Visión Ocular , Ecosistema
2.
Nature ; 574(7778): 372-377, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31619789

RESUMEN

Diabetes is far more prevalent in smokers than non-smokers, but the underlying mechanisms of vulnerability are unknown. Here we show that the diabetes-associated gene Tcf7l2 is densely expressed in the medial habenula (mHb) region of the rodent brain, where it regulates the function of nicotinic acetylcholine receptors. Inhibition of TCF7L2 signalling in the mHb increases nicotine intake in mice and rats. Nicotine increases levels of blood glucose by TCF7L2-dependent stimulation of the mHb. Virus-tracing experiments identify a polysynaptic connection from the mHb to the pancreas, and wild-type rats with a history of nicotine consumption show increased circulating levels of glucagon and insulin, and diabetes-like dysregulation of blood glucose homeostasis. By contrast, mutant Tcf7l2 rats are resistant to these actions of nicotine. Our findings suggest that TCF7L2 regulates the stimulatory actions of nicotine on a habenula-pancreas axis that links the addictive properties of nicotine to its diabetes-promoting actions.


Asunto(s)
Trastornos del Metabolismo de la Glucosa/genética , Habénula/metabolismo , Transducción de Señal , Tabaquismo/complicaciones , Proteína 2 Similar al Factor de Transcripción 7/metabolismo , Animales , AMP Cíclico/metabolismo , Glucosa/metabolismo , Trastornos del Metabolismo de la Glucosa/metabolismo , Humanos , Ratones , Mutagénesis , Nicotina/metabolismo , Células PC12 , Páncreas/metabolismo , Ratas , Receptores Nicotínicos/metabolismo , Tabaquismo/genética , Tabaquismo/metabolismo , Proteína 2 Similar al Factor de Transcripción 7/genética
3.
Transfusion ; 61(4): 1029-1034, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33231313

RESUMEN

BACKGROUND: Recent data suggests an association between blood hyperviscosity and both propensity for thrombosis and disease severity in patients with COVID-19. This raises the possibility that increased viscosity may contribute to endothelial damage and multiorgan failure in COVID-19, and that therapeutic plasma exchange (TPE) to decrease viscosity may improve patient outcomes. Here we sought to share our experience using TPE in the first 6 patients treated for COVID-19-associated hyperviscosity. STUDY DESIGN AND METHODS: Six critically ill COVID-19 patients with plasma viscosity levels ranging from 2.6 to 4.2 centipoise (cP; normal range, 1.4-1.8 cP) underwent daily TPE for 2-3 treatments. RESULTS: TPE decreased plasma viscosity in all six patients (Pre-TPE median 3.75 cP, range 2.6-4.2 cP; Post-TPE median 1.6 cP, range 1.5-1.9 cP). TPE also decreased fibrinogen levels in all five patients for whom results were available (Pre-TPE median 739 mg/dL, range 601-1188 mg/dL; Post-TPE median 359 mg/dL, range 235-461 mg/dL); D-dimer levels in all six patients (Pre-TPE median 5921 ng/mL, range 1134-60 000 ng/mL; Post-TPE median 4893 ng/mL, range 620-7518 ng/mL); and CRP levels in five of six patients (Pre-TPE median 292 mg/L, range 136-329 mg/L; Post-TPE median 84 mg/L, range 31-211 mg/L). While the two sickest patients died, significant improvement in clinical status was observed in four of six patients shortly after TPE. CONCLUSIONS: This series demonstrates the utility of TPE to rapidly correct increased blood viscosity in patients with COVID-19-associated hyperviscosity. Large randomized trials are needed to determine whether TPE may improve clinical outcomes for patients with COVID-19.


Asunto(s)
Viscosidad Sanguínea , COVID-19 , Intercambio Plasmático , SARS-CoV-2/metabolismo , Adulto , Anciano , COVID-19/sangre , COVID-19/terapia , Humanos , Masculino , Persona de Mediana Edad
4.
J Clin Apher ; 36(1): 34-40, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32894888

RESUMEN

INTRODUCTION: Extracorporeal photopheresis (ECP) is a procedure used to influence T-cell activity in patients suffering from immune-mediated cellular damage secondary to activated lymphocytes. Although well-tolerated, iron deficiency anemia (IDA) has been described. The goal herein is to describe IDA in patients who received extracorporeal photopheresis (ECP) treatment using UVAR (Therakos Inc) and CELLEX (Therakos Inc) instruments. DESIGN AND METHODS: Patients treated with ECP from 2015 to 2019 were retrospectively analyzed. IDA was defined by a decrease in hemoglobin following treatment with concomitant decrease in mean cell volume, mean corpuscular hemoglobin concentration, increased RBC distribution width, and/or iron studies compatible with IDA. RESULTS: During the four-year study period, thirty-four patients received ECP. Thirteen (38%) underwent treatment with the previous UVAR device while 21 (62%) received treatment on the newer CELLEX instrument. Nineteen (56%) of the cohort developed clinical and laboratory evidence of IDA with an average of 3.2 g/dL decrease in hemoglobin. Patients who developed IDA treated on the CELLEX instrument experienced a significantly greater drop in hemoglobin (P = .04) than those treated on the UVAR. Examining the CELLEX-treated patients, those who received the procedure at greater frequency experienced significantly greater drops in hemoglobin (P = .03). CONCLUSIONS: IDA is a risk of chronic ECP therapy and is likely secondary to retained blood components in the instrument. The temporal relationship between anemia and ECP treatment has a direct correlation with the treatment schedule. Patients undergoing ECP treatment should be closely monitored for the development of IDA.


Asunto(s)
Anemia Ferropénica/etiología , Fotoféresis/efectos adversos , Fotoféresis/instrumentación , Adulto , Anciano , Bronquiolitis Obliterante/terapia , Femenino , Enfermedad Injerto contra Huésped/terapia , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
5.
J Stroke Cerebrovasc Dis ; 30(3): 105592, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33454647

RESUMEN

BACKGROUND: Potential causes of embolic stroke of undetermined source (ESUS) include occult malignancy, venous thrombosis (VTE) with paradoxical embolism, and hypercoagulable disorders. Given the association of markers of coagulation and hemostatic activation (MOCHA) with these causes, the objective of this study was to validate the utility of the MOCHA profile in identifying the underlying cause of stroke. METHODS: We prospectively identified ESUS patients from January 1, 2017 to December 1, 2019 who underwent MOCHA profile (plasma d-dimer, prothrombin fragment 1.2, thrombin-antithrombin complex, fibrin monomer) testing. Abnormal MOCHA profile was defined as ≥ 2 abnormal markers. New diagnoses of malignancy, VTE, hypercoagulable disorders and recurrent stroke were identified during routine clinical follow-up. RESULTS: Of 236 ESUS patients, 104 (44%) patients had an abnormal MOCHA profile. In multivariable analyses the number of MOCHA abnormalities was significantly associated with malignancy, VTE, and hypercoagulable disorders (OR 2.59, CI 95% 1.78-3.76, p<0.001). Sensitivity, specificity, positive predictive value, and negative predictive value of an abnormal MOCHA profile for the combined outcome of malignancy, VTE, and hypercoagulability was 96%, 62%, 23%, and 99% respectively. DISCUSSION: The MOCHA profile was able to identify ESUS patients more likely to have malignancy, VTE, and hypercoagulable disorders during follow-up. Our results show that a normal MOCHA profile in ESUS patients can effectively rule out these potential causes of ESUS.


Asunto(s)
Accidente Cerebrovascular Embólico/etiología , Indicadores de Salud , Hemostasis , Neoplasias/diagnóstico , Trombofilia/diagnóstico , Tromboembolia Venosa/diagnóstico , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Coagulación Sanguínea , Accidente Cerebrovascular Embólico/sangre , Accidente Cerebrovascular Embólico/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/sangre , Neoplasias/complicaciones , Valor Predictivo de las Pruebas , Recurrencia , Reproducibilidad de los Resultados , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Trombofilia/sangre , Trombofilia/complicaciones , Tromboembolia Venosa/sangre , Tromboembolia Venosa/complicaciones
6.
J Am Chem Soc ; 142(43): 18565-18575, 2020 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-32991156

RESUMEN

When exposed to UV light, single crystals of the vinyl azides 3-azido-1-phenylpropenone (1a), 3-azido-1-(4-methoxyphenyl)propenone (1b), and 3-azido-1-(4-chlorophenyl)propenone (1c) exhibit dramatic mechanical effects by cracking or bending with the release of N2. Mechanistic studies using laser flash photolysis, supported by quantum mechanical calculations, show that each of the vinyl azides degrades through a vinylnitrene intermediate. However, despite having very similar crystal packing motifs, the three compounds exhibit distinct photomechanical responses in bulk crystals. While the crystals of 1a delaminate and release gaseous N2 indiscriminately under paraffin oil, the crystals of 1b and 1c visibly expand, bend, and fracture, mainly along specific crystallographic faces, before releasing N2. The photochemical analysis suggests that the observed expansion is due to internal pressure exerted by the gaseous product in the crystal lattices of these materials. Lattice energy calculations, supported by nanoindentation experiments, show significant differences in the respective lattice energies. The calculations identify critical features in the crystal structures of 1b and 1c where elastic energy accumulates during gas release, which correspond to the direction of the observed cracks. This study highlights the hitherto untapped potential of photochemical gas release to elicit a photomechanical response and motility of photoreactive molecular crystals.

7.
Transfusion ; 60(7): 1536-1543, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32588918

RESUMEN

BACKGROUND: The PLASMIC score is a rapid and inexpensive tool for predicting severe ADAMTS13 deficiency (activity <10%) in patients with suspected thrombotic thrombocytopenic purpura (TTP) by analyzing seven parameters (platelet count; combined hemolysis variable; absence of active neoplasia; absence of an organ or stem-cell transplant; mean corpuscular value; international normalized ratio; and serum creatinine). The purpose of this study was to validate the PLASMIC score at a large multi-institutional academic medical center. METHODS: An internal database of consultations to the transfusion medicine service, which oversees therapeutic apheresis at our institution, was reviewed to identify patients who were evaluated for and/or received plasma exchange for suspected TTP. These consultations covered the time period of January 2012 to February 2019. PLASMIC scoring criteria and ADAMTS13 assay results were abstracted from the electronic medical record, the PLASMIC score was calculated, and cases stratified into risk categories (low, intermediate, high risk) based on the score value. RESULTS: Of 58 patients identified, 46 met inclusion criteria, and 27 demonstrated ADAMTS13 activity <10%. Correlation of severe ADAMTS13 deficiency with risk-stratified groups resulted in 78% sensitivity, 63% specificity, 75% positive predictive value (PPV), and 67% negative predictive value (NPV). DISCUSSION: These findings paralleled those from validation studies performed at other institutions. They provided insufficient evidence to recommend routine use of the PLASMIC score to rule out TTP among patients at our hospitals. Nonetheless, these results reinforce the importance of early ADAMTS13 testing as a diagnostic triage tool for patients with suspected TTP.


Asunto(s)
Proteína ADAMTS13/sangre , Centros Médicos Académicos , Bases de Datos Factuales , Registros Electrónicos de Salud , Intercambio Plasmático , Púrpura Trombocitopénica Trombótica , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Púrpura Trombocitopénica Trombótica/sangre , Púrpura Trombocitopénica Trombótica/terapia , Estudios Retrospectivos
8.
Nicotine Tob Res ; 20(7): 789-799, 2018 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-29065200

RESUMEN

Introduction: Scientific discoveries over the past few decades have provided significant insight into the abuse liability and negative health consequences associated with tobacco and nicotine-containing products. While many of these advances have led to the development of policies and laws that regulate access to and formulations of these products, further research is critical to guide future regulatory efforts, especially as novel nicotine-containing products are introduced and selectively marketed to vulnerable populations. Discussion: In this narrative review, we provide an overview of the scientific findings that have impacted regulatory policy and discuss considerations for further translation of science into policy decisions. We propose that open, bidirectional communication between scientists and policy makers is essential to develop transformative preventive- and intervention-focused policies and programs to reduce appeal, abuse liability, and toxicity of the products. Conclusions: Through these types of interactions, collaborative efforts to inform and modify policy have the potential to significantly decrease the use of tobacco and alternative nicotine products and thus enhance health outcomes for individuals. Implications: This work addresses current topics in the nicotine and tobacco research field to emphasize the importance of basic science research and provide examples of how it can be utilized to inform public policy. In addition to relaying current thoughts on the topic from experts in the field, the article encourages continued efforts and communication between basic scientists and policy officials.


Asunto(s)
Investigación Biomédica/legislación & jurisprudencia , Nicotina , Política Pública/legislación & jurisprudencia , Productos de Tabaco/legislación & jurisprudencia , Investigación Biomédica/métodos , Humanos , Nicotina/normas , Productos de Tabaco/normas , Tabaquismo/prevención & control
11.
J Phys Chem A ; 118(45): 10433-47, 2014 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-25046555

RESUMEN

The irradiation of trans-vinylketones 1a-c yields the corresponding cis isomers 2a-c. Laser flash photolysis of 1a and 1b with 308 and 355 nm lasers results in their triplet ketones (T1K of 1), which rearrange to form triplet 1,2-biradicals 3a and 3b, respectively, whereas irradiation with a 266 nm laser produces their cis-isomers through singlet reactivity. Time-resolved IR spectroscopy of 1a with 266 nm irradiation confirmed that 2a is formed within the laser pulse. In comparison, laser flash photolysis of 1c with a 308 nm laser showed only the formation of 2c through singlet reactivity. At cryogenic temperatures, the irradiation of 1 also resulted in 2. DFT calculations were used to aid in the characterization of the excited states and biradicals involved in the cis-trans isomerization and to support the mechanism for the cis-trans isomerization on the triplet surface.

12.
Blood ; 115(9): 1823-34, 2010 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-20042723

RESUMEN

Lack of a dengue hemorrhagic animal model recapitulating human dengue virus infection has been a significant impediment in advancing our understanding of the early events involved in the pathogenesis of dengue disease. In efforts to address this issue, a group of rhesus macaques were intravenously infected with dengue virus serotype 2 (strain 16 681) at 1 x 10(7) PFU/animal. A classic dengue hemorrhage developed 3 to 5 days after infection in 6 of 6 animals. Blood chemistry appeared to be normal with exception of creatine phosphokinase, which peaked at 7 days after infection. A modest thrombocytopenia and noticeable neutropenia concomitant with slight decrease of hemoglobin and hematocrit were registered. In addition, the concentration of D-dimer was elevated significantly. Viremia peaked at 3 to 5 days after infection followed by an inverse relationship between T and B lymphocytes and a bimodal pattern for platelet-monocytes and platelet-neutrophil aggregates. Dengue virus containing platelets engulfed by monocytes was noted at 8 or 9 days after infection. Thus, rhesus macaques inoculated intravenously with a high dose of dengue virus produced dengue hemorrhage, which may provide a unique platform to define the early events in dengue virus infection and help identify which blood components contribute to the pathogenesis of dengue disease.


Asunto(s)
Dengue Grave/etiología , Animales , Virus del Dengue/patogenicidad , Modelos Animales de Enfermedad , Femenino , Humanos , Leucocitos/patología , Macaca mulatta , Masculino , Agregación Plaquetaria , Dengue Grave/sangre , Dengue Grave/patología , Dengue Grave/virología , Factores de Tiempo , Carga Viral
13.
Front Cardiovasc Med ; 9: 899594, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35845048

RESUMEN

Background: Platelet function testing to monitor antiplatelet therapy is important for reducing thromboembolic complications, yet variability across testing methods remains challenging. Here we evaluated the agreement of four different testing platforms used to monitor antiplatelet effects of aspirin (ASA) or P2Y12 inhibitors (P2Y12-I). Methods: Blood and urine specimens from 20 patients receiving dual antiplatelet therapy were analyzed by light transmission aggregometry (LTA), whole blood aggregometry (WBA), VerifyNow PRUTest and AspirinWorks. Result interpretation based on pre-defined cutoff values was used to calculate raw agreement indices, and Pearson's correlation coefficient determined using individual units of measure. Results: Agreement between LTA and WBA for P2Y12-I-response was 60% (r = 0.65, high-dose ADP; r = 0.75, low-dose ADP). VerifyNow agreed with LTA in 75% (r = 0.86, high-dose ADP; r = 0.75, low-dose ADP) and WBA in 55% (r = 0.57) of cases. Agreement between LTA and WBA for ASA-response was 45% (r = 0.09, high-dose collagen WBA; r = 0.19, low-dose collagen WBA). AspirinWorks agreed with LTA in 60% (r = 0.32) and WBA in 35% (r = 0.02, high-dose collagen WBA; r = 0.08, low-dose collagen WBA) of cases. Conclusions: Overall agreement varied from 35 to 75%. LTA and VerifyNow demonstrated the highest agreement for P2Y12-I-response, followed by moderate agreement between LTA and WBA. LTA and AspirinWorks showed moderate agreement for aspirin response, while WBA showed the weakest agreement with both LTA and AspirinWorks. The results from this study support the continued use of LTA for monitoring dual antiplatelet therapy, with VerifyNow as an appropriate alternative for P2Y12-I-response. Integration of results obtained from these varied testing platforms with patient outcomes remains paramount for future studies.

14.
Clin Appl Thromb Hemost ; 27: 10760296211032292, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34235983

RESUMEN

Measurement of a single marker of coagulation may not provide a complete picture of hemostasis activation and fibrinolysis in patients with chronic cardiovascular diseases. We assessed retrospective orders of a panel which included prothrombin fragment 1.2 (PF1.2), thrombin: antithrombin complexes, fibrin monomers, and D-dimers in patients with heart assist devices, cardiomyopathies, atrial fibrillation and intracardiac thrombosis (based on ordering ICD-10 codes). During 1 year there were 117 panels from 81 patients. Fifty-six (69%) patients had heart assist devices, cardiomyopathy was present in 17 patients (21%) and 29 patients (36%) had more than 1 condition. PF1.2 was most frequently elevated in patients with cardiomyopathy (61.1%) compared to those with cardiac assist devices (15.7%; P = 0.0002). D-dimer elevation was more frequent in patients with cardiac assist devices (98.8%) compared to those patients with cardiomyopathy (83.3%; P = 0.014). Patients with cardiomyopathy show increases of PF1.2 suggesting thrombin generation. In contrast, elevations of D-dimers without increase in other coagulation markers in patients with cardiac assist devices likely reflect the presence of the intravascular device and not necessarily evidence of hemostatic activation.


Asunto(s)
Anticoagulantes/uso terapéutico , Biomarcadores/sangre , Trastornos de la Coagulación Sanguínea/sangre , Enfermedades Cardiovasculares/sangre , Hemostasis/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/farmacología , Enfermedades Cardiovasculares/patología , Enfermedad Crónica , Humanos , Persona de Mediana Edad , Adulto Joven
15.
Am J Clin Pathol ; 155(4): 498-505, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33300981

RESUMEN

OBJECTIVES: Patients with coronavirus disease 2019 (COVID-19) have thromboembolic complications. Assessment of coagulation and other markers could be useful to understand their coagulopathy. METHODS: We performed a retrospective study of inflammatory and coagulation parameters, including prothrombin fragment 1.2 (PF1.2), thrombin-antithrombin complexes (TATs), fibrin monomers, and D-dimer, in hospitalized patients with COVID-19. We compared the markers in patients with thrombosis, admission to the intensive care unit (ICU), and poor outcome. RESULTS: Of the 81 patients, 9 (11%) experienced an acute thrombotic event (4 with pulmonary embolism, 3 with venous thrombosis, and 2 with stroke). PF1.2 was elevated in 32 (39%) patients, TATs in 54 (67%), fibrin monomers in 49 (60%), and D-dimer in 76 (94%). Statistically significant elevation in PF1.2 and TATs was seen in patients admitted to the ICU, while D-dimer and fibrin monomers were significantly elevated in patients with poor outcomes. The presence of multiple abnormal coagulation parameters was associated with ICU admission. Other parameters with statistically significant results included abnormal WBC counts and elevated C-reactive protein, which were associated with ICU admission and poor outcomes. CONCLUSIONS: Our data demonstrate that abnormalities of biomarkers of hemostasis activation and inflammatory markers are associated with poor outcomes in patients with COVID-19.


Asunto(s)
Biomarcadores/sangre , Trastornos de la Coagulación Sanguínea/diagnóstico , Trastornos de la Coagulación Sanguínea/virología , COVID-19/complicaciones , Hemostasis , Adulto , Anciano , Anciano de 80 o más Años , Trastornos de la Coagulación Sanguínea/sangre , Pruebas de Coagulación Sanguínea , COVID-19/sangre , COVID-19/diagnóstico , COVID-19/fisiopatología , Femenino , Hospitalización , Humanos , Inflamación/sangre , Inflamación/diagnóstico , Inflamación/virología , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
16.
Front Neurol ; 12: 695378, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34163432

RESUMEN

Background: The objective of this study was to evaluate if anticoagulation therapy reduces recurrent stroke in embolic stroke of undetermined source (ESUS) patients with left atrial enlargement (LAE) or abnormal markers of coagulation and hemostatic activity (MOCHA) compared to antiplatelet therapy. Methods: ESUS patients from January 1, 2017, to June 30, 2019, underwent outpatient cardiac monitoring and the MOCHA profile (serum d-dimer, prothrombin fragment 1.2, thrombin-antithrombin complex, and fibrin monomer). Anticoagulation was offered to patients with abnormal MOCHA (≥2 elevated markers) or left atrial volume index 40 mL/m2. Patients were evaluated for recurrent stroke or major hemorrhage at routine clinical follow-up. We compared this patient cohort (cohort 2) to a historical cohort (cohort 1) who underwent the same protocol but remained on antiplatelet therapy. Results: Baseline characteristics in cohort 2 (n = 196; mean age = 63 ± 16 years, 59% female, 49% non-White) were similar to cohort 1 (n = 42) except that cohort 2 had less diabetes (43 vs. 24%, p = 0.01) and more tobacco use (26 vs. 43%, p = 0.04). Overall, 45 patients (23%) in cohort 2 initiated anticoagulation based on abnormal MOCHA or LAE. During mean follow-up of 13 ± 10 months, cohort 2 had significantly lower recurrent stroke rates than cohort 1 (14 vs. 3%, p = 0.009) with no major hemorrhages. Conclusions: Anticoagulation therapy in a subgroup of ESUS patients with abnormal MOCHA or severe LAE may be associated with a reduced rate of recurrent stroke compared to antiplatelet therapy. A prospective, randomized study is warranted to validate these results.

17.
PLoS One ; 16(3): e0248230, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33740793

RESUMEN

BACKGROUND: There is limited data on the markers of coagulation and hemostatic activation (MOCHA) profile in Coronavirus disease 2019 (COVID-19) and its ability to identify COVID-19 patients at risk for thrombotic events and other complications. METHODS: Hospitalized patients with confirmed SARS-COV-2 from four Atlanta hospitals were included in this observational cohort study and underwent admission testing of MOCHA parameters (plasma d-dimer, prothrombin fragment 1.2, thrombin-antithrombin complex, fibrin monomer). Clinical outcomes included deep vein thrombosis, pulmonary embolism, myocardial infarction, ischemic stroke, access line thrombosis, ICU admission, intubation and mortality. MAIN RESULTS: Of 276 patients (mean age 59 ± 6.4 years, 47% female, 62% African American), 45 (16%) had a thrombotic endpoint. Each MOCHA parameter was independently associated with a thrombotic event (p<0.05) and ≥ 2 abnormalities was associated with thrombotic endpoints (OR 3.3, 95% CI 1.2-8.8) as were admission D-dimer ≥ 2000 ng/mL (OR 3.1, 95% CI 1.5-6.6) and ≥ 3000 ng/mL (OR 3.6, 95% CI 1.6-7.9). However, only ≥ 2 MOCHA abnormalities were associated with ICU admission (OR 3.0, 95% CI 1.7-5.2) and intubation (OR 3.2, 95% CI 1.6-6.4). MOCHA and D-dimer cutoffs were not associated with mortality. MOCHA with <2 abnormalities (26% of the cohort) had 89% sensitivity and 93% negative predictive value for a thrombotic endpoint. CONCLUSIONS: An admission MOCHA profile is useful to risk-stratify COVID-19 patients for thrombotic complications and more effective than isolated d-dimer for predicting risk of ICU admission and intubation.


Asunto(s)
Antitrombina III/análisis , COVID-19/patología , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Fragmentos de Péptidos/análisis , Péptido Hidrolasas/análisis , Protrombina/análisis , Trombosis/diagnóstico , Anciano , Área Bajo la Curva , COVID-19/complicaciones , COVID-19/mortalidad , COVID-19/virología , Estudios de Cohortes , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Admisión del Paciente , Curva ROC , Factores de Riesgo , SARS-CoV-2/aislamiento & purificación , Tasa de Supervivencia , Trombosis/complicaciones
18.
Transfusion ; 50(10): 2193-8, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20456709

RESUMEN

BACKGROUND: Platelet (PLT) storage adversely affects PLT structure and function in vitro and is associated with decreased PLT recovery and function in vivo. In pediatric transfusion medicine, it is not uncommon for small residual volumes to remain in parent units after aliquot preparation of leukoreduced apheresis-derived PLTs (LR-ADP). However, limited data exist regarding the impact of storage on residual small-volume LR-ADP. STUDY DESIGN AND METHODS: Standard metabolic testing was performed on residual volumes of LR-ADP after aliquot removal and PLT aggregometry using a dual agonist of ADP and collagen was performed on stored, small-volume aliquots (10-80mL) created from an in vitro model of PLT storage. RESULTS: Seventy-seven LR-ADP underwent metabolic (n=67) or metabolic and aggregation (n=10) studies. All products maintained a pH value of more than 6.89 throughout storage. Lactate and pCO(2) increased proportionally with longer storage time. Regardless of acceptable metabolism during storage, aggregation in 10- to 20-mL aliquots was impaired by Day 4 and aliquots less than 40 mL demonstrated the most dramatic decrease in aggregation from baseline. CONCLUSIONS: Despite maintenance of acceptable metabolic conditions, residual volumes of LR-ADP develop impaired aggregation in vitro that may adversely affect PLT survival and function in vivo. At volumes below 40mL, LR-ADP revealed reduced aggregation. As a result, it is recommended to monitor and record volumes of LR-ADP used for pediatric transfusion. Moreover, once LR-ADP attain a volume of 50mL or less on Day 4 or Day 5 of storage, consider discarding these products until their in vivo efficacy can be studied.


Asunto(s)
Plaquetas/citología , Plaquetas/metabolismo , Conservación de la Sangre/métodos , Transfusión de Plaquetas/métodos , Plaquetoferesis/métodos , Niño , Humanos , Factores de Tiempo
19.
Ann Bot ; 106(6): 927-44, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20880934

RESUMEN

BACKGROUND AND AIMS: The Asian genus Vigna, to which four cultivated species (rice bean, azuki bean, mung bean and black gram) belong, is suitable for comparative genomics. The aims were to construct a genetic linkage map of rice bean, to identify the genomic regions associated with domestication in rice bean, and to compare these regions with those in azuki bean. METHODS: A genetic linkage map was constructed by using simple sequence repeat and amplified fragment length polymorphism markers in the BC(1)F(1) population derived from a cross between cultivated and wild rice bean. Using this map, 31 domestication-related traits were dissected into quantitative trait loci (QTLs). The genetic linkage map and QTLs of rice bean were compared with those of azuki bean. KEY RESULTS: A total of 326 markers converged into 11 linkage groups (LGs), corresponding to the haploid number of rice bean chromosomes. The domestication-related traits in rice bean associated with a few major QTLs distributed as clusters on LGs 2, 4 and 7. A high level of co-linearity in marker order between the rice bean and azuki bean linkage maps was observed. Major QTLs in rice bean were found on LG4, whereas major QTLs in azuki bean were found on LG9. CONCLUSIONS: This is the first report of a genetic linkage map and QTLs for domestication-related traits in rice bean. The inheritance of domestication-related traits was so simple that a few major QTLs explained the phenotypic variation between cultivated and wild rice bean. The high level of genomic synteny between rice bean and azuki bean facilitates QTL comparison between species. These results provide a genetic foundation for improvement of rice bean; interchange of major QTLs between rice bean and azuki bean might be useful for broadening the genetic variation of both species.


Asunto(s)
Fabaceae/genética , Genoma de Planta/genética , Genómica , Sitios de Carácter Cuantitativo/genética
20.
Transfus Med Rev ; 34(3): 178-187, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32826130

RESUMEN

Passenger lymphocyte syndrome (PLS) is caused by the transfer of B-lymphocytes present in the donor graft into the recipient circulation following solid organ or hematopoietic stem cell transplantation. These cells may produce antibodies against the recipient's red blood cells, thereby triggering antibody dependent cytotoxicity and erythroid clearance, with potential resulting hemolysis and jaundice. Although uncommon, the true incidence is unknown because many cases are subclinical, with only serologic findings or with non significant levels of hemolysis detectable clinically or by laboratory monitoring. Thus, these cases may not be detected in the immediate perioperative period. No standardized consensus exists on screening for PLS in patients. Through a review of the literature from 2009 to 2019, we aim to approximate the incidence of this condition in different solid organ transplant settings, as well as to streamline recognition, detection, and management of PLS early in the disease course to prevent adverse outcomes and minimize invasive therapy. The resultant literature review yielded 22 case reports and 8 case series comprising 71 solid organ transplant patients. Hematopoietic stem cell transplant cases were excluded, as PLS cases related to solid organ transplant were the primary focus of this review. Our institution has traditionally handled PLS on a case-by-case basis, although we hope to improve this process through an introduction of an algorithm based on review of the literature and formalized communication with primary caregivers.


Asunto(s)
Linfocitos B/inmunología , Linfocitos B/trasplante , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Enfermedades del Sistema Inmune/etiología , Isoanticuerpos/inmunología , Trasplante de Órganos/efectos adversos , Complicaciones Posoperatorias , Humanos , Enfermedades del Sistema Inmune/diagnóstico , Enfermedades del Sistema Inmune/inmunología , Enfermedades del Sistema Inmune/terapia , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/inmunología , Complicaciones Posoperatorias/terapia , Síndrome
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