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1.
Hematol Oncol Clin North Am ; 36(6): 1271-1284, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36400543

RESUMEN

Patients with sickle cell disease (SCD) have a high rate of red cell alloimmunization, which increases morbidity and mortality. Reasons for this susceptibility are multifactorial, but differences in antigen frequency between donors and recipients are one of the modifiable risk factors. Here, we evaluate the benefits of red cell molecular antigen-typing for both patients with SCD and their donors and describe how results from these critical tests could be used to enhance patient safety.


Asunto(s)
Anemia de Células Falciformes , Isoanticuerpos , Humanos , Genotipo , Anemia de Células Falciformes/genética , Anemia de Células Falciformes/terapia , Transfusión Sanguínea , Eritrocitos
2.
Br J Haematol ; 189(4): 635-639, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32330288

RESUMEN

With the developing COVID-19 pandemic, patients with inherited anaemias require specific advice regarding isolation and changes to usual treatment schedules. The National Haemoglobinopathy Panel (NHP) has issued guidance on the care of patients with sickle cell disease, thalassaemia, Diamond Blackfan anaemia (DBA), congenital dyserythropoietic anaemia (CDA), sideroblastic anaemia, pyruvate kinase deficiency and other red cell enzyme and membrane disorders. Cascading of accurate information for clinicians and patients is paramount to preventing adverse outcomes, such as patients who are at increased risk of fulminant bacterial infection due to their condition or its treatment erroneously self-isolating if their fever is mistakenly attributed to a viral cause, delaying potentially life-saving antibiotic therapy. Outpatient visits should be minimised for most patients, however some, such as first transcranial dopplers for children with sickle cell anaemia should not be delayed as known risk of stroke will outweigh the unknown risk from COVID-19 infection. Blood transfusion programmes should be continued, but specific changes to usual clinical pathways can be instituted to reduce risk of patient exposure to COVID-19, as well as contingency planning for possible reductions in blood available for transfusions. Bone marrow transplants for these disorders should be postponed until further notice. With the current lack of evidence on the risk and complications of COVID-19 infection in these patients, national data collection is ongoing to record outcomes and eventually to identify predictors of disease severity, particularly important if further waves of infection travel through the population.


Asunto(s)
Anemia/complicaciones , Anemia/terapia , Betacoronavirus , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/prevención & control , Pandemias/prevención & control , Neumonía Viral/complicaciones , Neumonía Viral/prevención & control , Transfusión Sanguínea , Trasplante de Médula Ósea , COVID-19 , Infección Hospitalaria/prevención & control , Humanos , SARS-CoV-2
3.
Hematology Am Soc Hematol Educ Program ; 2019(1): 505-512, 2019 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-31808832

RESUMEN

In countries with access to organized health care, survival of children with sickle cell disease (SCD) has greatly improved, resulting in a growing population of adults with SCD. Transition from pediatric to adult care presents many challenges for the patient, who now faces the reality of emerging complications in many organs that are cumulative, adding to other age-related nonsickle conditions that interact and add to the disease morbidity. We recommend regular comprehensive annual assessments, monitoring for early signs of organ damage and joint clinics with relevant specialists, if applicable. While maintaining a low threshold for intervention with disease-modifying therapies, we should always keep in mind that there is no single complication that is pathognomonic of SCD, and nonsickle comorbidities should always be excluded and treated if present. We need to reevaluate our approach to managing adults with SCD by putting a greater emphasis on multidisciplinary care while proactively considering curative options (hematopoietic stem cell transplant and gene therapy) and experimental pharmacological agents for adults with SCD of all ages before complications render the patients ineligible for these treatments.


Asunto(s)
Anemia de Células Falciformes , Transición a la Atención de Adultos , Adulto , Anemia de Células Falciformes/diagnóstico , Anemia de Células Falciformes/genética , Anemia de Células Falciformes/patología , Anemia de Células Falciformes/terapia , Niño , Femenino , Humanos
4.
Br J Haematol ; 180(4): 607-617, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29377071

RESUMEN

Sickle cell disease is one of the commonest serious inherited diseases in the world, and red cell transfusion is still one of the few effective treatments for acute and chronic complications. Transfusion corrects anaemia and dilutes out the number of red cells able to cause vaso-occlusion and vascular damage. Urgent red cell transfusions are used to correct acute anaemia, treat acute chest syndrome and patients with acute neurological symptoms. We use elective transfusions preoperatively for moderate risk surgery, and in some pregnant women. There is good evidence for the use of long-term regular transfusions in primary stroke prevention, with the aim of keeping the percentage of sickle haemoglobin below 30%. Long-term transfusions are also used in secondary stroke prevention, and the management of progressive organ damage, including renal impairment and pulmonary hypertension. Blood needs to be matched for ABO, RH and Kell, although alloantibodies may still develop and require more careful, extended cross-matching. Delayed haemolytic transfusion reactions are relatively common, difficult to diagnose and manage, and potentially fatal.


Asunto(s)
Anemia de Células Falciformes/terapia , Transfusión de Eritrocitos , Factores de Edad , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/diagnóstico , Anemia de Células Falciformes/etiología , Donantes de Sangre , Manejo de la Enfermedad , Transfusión de Eritrocitos/efectos adversos , Transfusión de Eritrocitos/métodos , Genotipo , Humanos , Difusión de la Información , Isoanticuerpos/sangre , Isoanticuerpos/inmunología , Fenotipo , Factores de Tiempo , Reacción a la Transfusión , Espera Vigilante
5.
Curr Clin Pharmacol ; 12(2): 92-98, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28578646

RESUMEN

BACKGROUND: Ultrasound-guided supraclavicular brachial plexus block (USSB) provides excellent postoperative analgesia after upper extremity surgery. Dexamethasone and clonidine have been added to local anesthetics to enhance and prolong the duration of analgesia. OBJECTIVE: The objective of this randomized prospective study is to evaluate the efficacy of dexamethasone, clonidine, or combination of both as adjuvants to ropivacaine on the duration of USSB for postoperative analgesia. METHODS: Patients receiving USSB for postoperative pain control for upper extremity surgery were randomized to one of four groups; ropivacaine 0.5%, ropivacaine 0.5% with 4 mg dexamethasone, ropivacaine 0.5% with 100 mcg clonidine , or ropivacaine 0.5% with 4 mg dexamethasone and 100 mcg clonidine. Pain scores, sensory and motor function were evaluated at post anesthesia care unit (PACU), discharge and at 24 h postoperatively. RESULTS: The duration of sensory and motor blocks was significantly longer in clonidine groups when compared to ropivacaine alone [Sensorial analgesia: ropivacaine alone 13.4±6, Ropivacaine- Clonidine 17.4±6; Ropivacaine-Dexamethasone-Clonidine 18.8±6.2; Motor blocks: Ropivacaine 12±5, Ropivacaine-Clonidine 16.8±5.2, Ropivacaine-Dexamethasone-Clonidine 18.2±5.7]. In clonidine groups, there was significant prolongation of motor and sensory block when compared to ropivacaine group alone. CONCLUSION: The results demonstrated that clonidine significantly prolongs the duration of ropivacaine effects for the postoperative analgesia in patient underwent upper arm surgeries.


Asunto(s)
Bloqueo del Plexo Braquial/métodos , Clonidina/administración & dosificación , Dexametasona/administración & dosificación , Dolor Postoperatorio/prevención & control , Ropivacaína/administración & dosificación , Adulto , Anciano , Analgésicos/administración & dosificación , Anestésicos Locales/administración & dosificación , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Estudios Prospectivos , Factores de Tiempo , Ultrasonografía Intervencional/métodos , Extremidad Superior/cirugía
6.
Cochrane Database Syst Rev ; 4: CD002202, 2017 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-28426137

RESUMEN

BACKGROUND: Sickle cell disease (SCD) is one of the most common inherited diseases worldwide. It is associated with lifelong morbidity and a reduced life expectancy. Hydroxyurea (hydroxycarbamide), an oral chemotherapeutic drug, ameliorates some of the clinical problems of SCD, in particular that of pain, by raising fetal haemoglobin. This is an update of a previously published Cochrane Review. OBJECTIVES: To assess the effects of hydroxyurea therapy in people with SCD (all genotypes), of any age, regardless of setting. SEARCH METHODS: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Register, comprising of references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also searched online trial registries.Date of the most recent search: 16 January 2017. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials, of one month or longer, comparing hydroxyurea with placebo, standard therapy or other interventions for people with SCD. DATA COLLECTION AND ANALYSIS: Authors independently assessed studies for inclusion, carried out data extraction and assessed the risk of bias. MAIN RESULTS: Seventeen studies were identified in the searches; eight randomised controlled trials were included, recruiting 899 adults and children with SCD (haemoglobin SS (HbSS), haemoglobin SC (HbSC) or haemoglobin Sߺthalassaemia (HbSߺthal) genotypes). Studies lasted from six to 30 months.Four studies (577 adults and children with HbSS or HbSߺthal) compared hydroxyurea to placebo; three recruited individuals with only severe disease and one recruited individuals with all disease severities. There were statistically significant improvements in terms of pain alteration (using measures such as pain crisis frequency, duration, intensity, hospital admissions and opoid use), measures of fetal haemoglobin and neutrophil counts and fewer occurrences of acute chest syndrome and blood transfusions in the hydroxyurea groups. There were no consistent statistically significant differences in terms of quality of life and adverse events (including serious or life-threatening events). Seven deaths occurred during the studies, but the rates by treatment group were not statistically significantly different.Two studies (254 children with HbSS or HbSߺthal also with risk of primary or secondary stroke) compared hydroxyurea and phlebotomy to transfusion and chelation; there were statistically significant improvements in terms of measures of fetal haemoglobin and neutrophil counts, but more occurrences of acute chest syndrome and infections in the hydroxyurea and phlebotomy group. There were no consistent statistically significant differences in terms of pain alteration and adverse events (including serious or life-threatening events). Two deaths occurred during the studies (one in a the hydroxyurea treatment arm and one in the control arm), but the rates by treatment group were not statistically significantly different. In the primary prevention study, no strokes occurred in either treatment group but in the secondary prevention study, seven strokes occurred in the hydroxyurea and phlebotomy group (none in the transfusion and chelation group) and the study was terminated early.The quality of the evidence for the above two comparisons was judged as moderate to low as the studies contributing to these comparisons were mostly large and well designed (and at low risk of bias); however evidence was limited and imprecise for some outcomes such as quality of life, deaths during the studies and adverse events and results are applicable only to individuals with HbSS and HbSߺthal genotypes.Of the remaining two studies, one (22 children with HbSS or HbSߺthal also at risk of stoke) compared hydroxyurea to observation; there were statistically significant improvements in terms of measures of fetal haemoglobin and neutrophil counts but no statistically significant differences in terms of adverse events (including serious or life-threatening events).The final study (44 adults and children with HbSC) compared treatment regimens with and without hydroxyurea - there was statistically significant improvement in terms of measures of fetal haemoglobin, but no statistically significant differences in terms of adverse events (including serious or life-threatening events). No participants died in either of these studies and other outcomes relevant to the review were not reported.The quality of the evidence for the above two comparisons was judged to be very low due to the limited number of participants, the lack of statistical power (as both studies were terminated early with approximately only 20% of their target sample size recruited) and the lack of applicability to all age groups and genotypes. AUTHORS' CONCLUSIONS: There is evidence to suggest that hydroxyurea is effective in decreasing the frequency of pain episodes and other acute complications in adults and children with sickle cell anaemia of HbSS or HbSߺthal genotypes and in preventing life-threatening neurological events in those with sickle cell anaemia at risk of primary stroke by maintaining transcranial doppler velocities. However, there is still insufficient evidence on the long-term benefits of hydroxyurea, particularly in preventing chronic complications of SCD, recommending a standard dose or dose escalation to maximum tolerated dose. There is also insufficient evidence about the long-term risks of hydroxyurea, including its effects on fertility and reproduction. Evidence is also limited on the effects of hydroxyurea on individuals with HbSC genotype. Future studies should be designed to address such uncertainties.


Asunto(s)
Anemia de Células Falciformes/tratamiento farmacológico , Antidrepanocíticos/uso terapéutico , Hidroxiurea/uso terapéutico , Adulto , Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/mortalidad , Antidrepanocíticos/efectos adversos , Terapia por Quelación , Niño , Transfusión de Eritrocitos , Genotipo , Enfermedad de la Hemoglobina SC/sangre , Enfermedad de la Hemoglobina SC/tratamiento farmacológico , Humanos , Hidroxiurea/efectos adversos , Flebotomía/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Espera Vigilante
7.
Theriogenology ; 89: 192-200, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28043351

RESUMEN

A reproductive analysis of a captive group of jaguars (Panthera onca; n = 6) at the Santacruz Zoological Foundation in Cundinamarca, Colombia, was conducted by performing a longitudinal, noninvasive, hormonal analysis of estradiol and progestogens in females and of androgens in males. During four seasons, female jaguars confined in solitary were evaluated for ovarian activity and spontaneous ovulation, male jaguars for testicular activity. A second hormonal follow-up was conducted in the females after administration of gonadotropins. Hormones were extracted from fecal samples of three females (n = 3) and two males (n = 2). Estradiol measurements were obtained by RIA and progestogens by enzyme immunoassay. The linear mixed-effect regression showed that there was a significant effect of seasons in the concentrations of estradiol (chi square = 15.97, degrees of freedom = 3, P < 0.01). Posthoc comparisons of all pairs of seasonal means were conducted according to Tukey's honest significant difference, revealing significant differences between seasons: Dry 1 versus Rains 2 (P < 0.01), Rains 1 versus Rains 2 (P < 0.05), and Dry 2 versus Rains 2 (P < 0.05). Elevations of progestogens compatible with spontaneous ovulation occurred in three jaguars, and the linear mixed-effect regression showed that there was also a significant effect of seasons (chi square = 28.56, degrees of freedom = 3, P < 0.01). Posthoc comparisons showed significant differences only between seasons: Dry 2 versus Rains 2 (P < 0.01). The season with the lowest average concentration was Rains 2 (October, November, and December). During this season, periods of anestrous were registered that lasted between 31 and 83 days. The three females presented estradiol peaks after the administration of eCG. A noninvasive longitudinal analysis for androgens was also made (males 1 and 2) over the course of 1 year, and no significant differences were found between the different seasons. A seminal analysis of three adult male jaguars (Panthera onca; n = 3) was also performed after electroejaculation under general anesthesia (male 1 and 2) and by a postmortem epididymal wash (male 3). The mean concentration of spermatozoids was 5.7 × 106 ± 1.1 × 106 spermatozoa/mL. The progressive motility + standard deviation averaged 80%. The percentage of normal spermatozoids obtained by electroejaculation was 80 ± 2.8%, and the abnormalities found more frequently were head defects (7 ± 1.4%). The seminal fluid obtained by epididymal flush contained 35 ± 1.4% normal spermatozoids, and the most frequent abnormalities found corresponded to distal cytoplasmic droplets (39 ± 11.3%).


Asunto(s)
Fertilidad , Panthera/fisiología , Andrógenos/metabolismo , Animales , Colombia , Estradiol/metabolismo , Femenino , Gonadotropinas/farmacología , Modelos Lineales , Estudios Longitudinales , Masculino , Detección de la Ovulación/veterinaria , Inducción de la Ovulación/veterinaria , Progestinas/metabolismo , Estaciones del Año , Análisis de Semen/veterinaria
8.
Hip Int ; 26(2): 186-92, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26692246

RESUMEN

BACKGROUND: Sickle cell disease (SCD) affects around 80,000 people in the USA and 12,000 in the UK. Up to 40% of patients will get osteonecrosis of the femoral head. Cemented acetabular components yield poor results with the rate of osteolysis ranging from 13.5 to 46%. We report on a consecutive cohort of patients with SCD who underwent uncemented THA with ceramic-on-ceramic (CoC) bearings. METHODS: Since 2002 52 primary THAs were carried out in 40 patients. The average age was 36.1 years (17-54). 48 cases had exchange blood transfusion preoperatively and 3 had top-up transfusions.An S-ROM was used in 47 hips a Solutions stem in 4 hips and an AML in 1. It was necessary to drill the femur during 12 hips. There were 5 intra-operative peri-prosthetic fractures. 2 dislocations were observed. 2 superficial infections were detected. RESULTS: All components have in-grown. There have been no cases of radiographic osteolysis, migration or loosening of the hip with average 5-year (2-10.1) follow-up. CONCLUSIONS: The combination of a multidisciplinary team approach and uncemented implants, with ceramic-on-ceramic bearings used, has made THA in patients with SCD a safe and reliable procedure in our hospital.


Asunto(s)
Anemia de Células Falciformes/complicaciones , Artroplastia de Reemplazo de Cadera/métodos , Articulación de la Cadera/cirugía , Prótesis de Cadera , Artropatías/cirugía , Complicaciones Posoperatorias/epidemiología , Adolescente , Adulto , Anemia de Células Falciformes/terapia , Transfusión Sanguínea , Femenino , Estudios de Seguimiento , Articulación de la Cadera/diagnóstico por imagen , Humanos , Incidencia , Artropatías/complicaciones , Artropatías/diagnóstico , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios/métodos , Diseño de Prótesis , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos/epidemiología , Adulto Joven
9.
Platelets ; 26(5): 474-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25140584

RESUMEN

Platelets of patients with sickle cell disease (SCD) show evidence of mild activation in the non-crisis steady state and greater activation during vaso-occlusive crises (VOC). Prasugrel, a potent inhibitor of ADP-mediated platelet activation and aggregation, may be useful in attenuating VOC. We compared platelet responses to ADP stimulation in patients with SCD and healthy subjects before and after treatment with prasugrel. In a phase 1 study, platelet biomarker levels were assessed in 12 adult patients with SCD and 13 healthy subjects before and after 12 ± 2 days of 5.0 or 7.5 mg/day prasugrel. The following were determined in whole blood samples stimulated with 20 µM ADP: (i) percentages of monocytes and neutrophils with adherent platelets (cell-platelet aggregates); (ii) the relative number (mass) of platelets associated with each monocyte and neutrophil as reported by CD61 mean fluorescence intensity (MFI) of the monocyte-platelet and neutrophil-platelet aggregates; (iii) the percentages of platelets positive for surface expression of CD40 ligand (CD40L), P-selectin (CD62p) and activated glycoprotein IIb-IIIa (GPIIb-IIIa); and (iv) the percentages of platelets and monocyte-platelet aggregates positive for surface tissue factor (TF) expression. At baseline, there were no significant differences between cohorts in the percentages of platelets expressing activation biomarkers. Following 12 days of prasugrel administration, the percentages of platelets expressing activation biomarkers following ADP stimulation were reduced in both cohorts, and there were no significant differences between groups. Both patients with SCD and healthy subjects had significant reductions in the monocyte-platelet and neutrophil-platelet aggregate MFI and the percentage of platelets expressing P-selectin and activated GPIIb-IIIa (all p < 0.05). Healthy subjects also had significant reductions in monocyte-platelet aggregate percentages (p = 0.004), neutrophil-platelet aggregate percentages (p = 0.011) and the percentage of CD40L-positive platelets (p = 0.044) that were not observed in patients with SCD. Prasugrel administration to SCD patients attenuates ex vivo ADP-stimulated platelet activation as measured by the percentage of platelets positive for P-selectin and GPIIb-IIIa, thus reducing the proportion of platelets that may participate in aggregates. Furthermore, prasugrel decreases ex vivo ADP-stimulated platelet aggregation with monocytes and neutrophils as measured by the monocyte-platelet and neutrophil-platelet aggregate MFI. This implies that in the presence of prasugrel, fewer platelets adhere to monocytes and neutrophils, which may result in reducing cell-platelet aggregate size. Therefore, reduced platelet reactivity and decreased size of leukocyte-platelet aggregates suggest additional mechanisms by which prasugrel may provide benefit to patients with SCD and support further investigation of possible therapeutic benefits of prasugrel in this population.


Asunto(s)
Adenosina Difosfato/metabolismo , Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/tratamiento farmacológico , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Activación Plaquetaria/efectos de los fármacos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Clorhidrato de Prasugrel/uso terapéutico , Adenosina Difosfato/farmacología , Adulto , Biomarcadores , Estudios de Casos y Controles , Femenino , Humanos , Leucocitos/efectos de los fármacos , Leucocitos/metabolismo , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/farmacología , Clorhidrato de Prasugrel/farmacología , Adulto Joven
10.
Ann Hum Genet ; 78(6): 434-51, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25069958

RESUMEN

HMIP-2 is a human quantitative trait locus affecting peripheral numbers, size and hemoglobin composition of red blood cells, with a marked effect on the persistence of the fetal form of hemoglobin, HbF, in adults. The locus consists of multiple common variants in an enhancer region for MYB (chr 6q23.3), which encodes the hematopoietic transcription factor cMYB. Studying a European population cohort and four African-descended groups of patients with sickle cell anemia, we found that all share a set of two spatially separate HbF-promoting alleles at HMIP-2, termed "A" and "B." These typically occurred together ("A-B") on European chromosomes, but existed on separate homologous chromosomes in Africans. Using haplotype signatures for "A" and "B," we interrogated public population datasets. Haplotypes carrying only "A" or "B" were typical for populations in Sub-Saharan Africa. The "A-B" combination was frequent in European, Asian, and Amerindian populations. Both alleles were infrequent in tropical regions, possibly undergoing negative selection by geographical factors, as has been reported for malaria with other hematological traits. We propose that the ascertainment of worldwide distribution patterns for common, HbF-promoting alleles can aid their further genetic characterization, including the investigation of gene-environment interaction during human migration and adaptation.


Asunto(s)
Anemia de Células Falciformes/genética , Elementos de Facilitación Genéticos , Eritrocitos/citología , Sitios de Carácter Cuantitativo , Alelos , Población Negra/genética , Interacción Gen-Ambiente , Estudios de Asociación Genética , Genética de Población , Genoma Humano , Genotipo , Haplotipos , Humanos , Proteínas Proto-Oncogénicas c-myb/genética , Análisis de Secuencia de ADN , Población Blanca/genética
11.
Thromb Res ; 133(2): 190-5, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24368019

RESUMEN

INTRODUCTION: Prasugrel, a P2Y12 adenosine diphosphate (ADP) receptor antagonist effectively inhibits ADP-mediated platelet activation and aggregation, and may be useful in reducing vaso-occlusive crises in sickle cell disease (SCD). In this study, we assess the effect of prasugrel on biomarkers of platelet activation and coagulation in patients with SCD. MATERIALS AND METHODS: Twelve adult patients with SCD and 13 healthy subjects were examined before and after 12 ± 2 days of 5.0 or 7.5 mg/day oral prasugrel. Assessed cellular biomarkers included monocyte- and neutrophil-platelet aggregates, activated glycoprotein IIb-IIIa (GPIIbIIIa), P-selectin, CD40 ligand (CD40L), tissue factor (TF) expression on circulating platelets and on monocyte-platelet aggregates, and platelet-erythrocyte aggregates. Soluble biomarkers included CD40L, prothrombin fragment 1.2 (F1.2), thromboxane B2 (TXB2), P-selectin, and TF. RESULTS: Patients with SCD had increased platelet baseline activation compared to healthy subjects, as measured by percentages of monocyte-platelet aggregates, neutrophil-platelet aggregates, and platelets expressing CD40L. Likewise, baseline levels of soluble F1.2 and TXB2 were elevated in patients with SCD compared to healthy subjects. After 12 days of prasugrel, patients with SCD had a significant reduction in platelet-monocyte aggregates that was not observed in healthy subjects. Following prasugrel administration, those with SCD maintained higher levels of monocyte-platelet aggregates and soluble F1.2, but had lower levels of platelet-erythrocyte aggregates and soluble TF compared to healthy subjects. CONCLUSIONS: These results provide evidence for chronic platelet activation in the SCD steady state, activation that was in part attenuated by prasugrel, thereby suggesting that ADP may mediate platelet activation in SCD.


Asunto(s)
Anemia de Células Falciformes/tratamiento farmacológico , Coagulación Sanguínea/efectos de los fármacos , Plaquetas/efectos de los fármacos , Piperazinas/uso terapéutico , Activación Plaquetaria/efectos de los fármacos , Antagonistas del Receptor Purinérgico P2Y/uso terapéutico , Tiofenos/uso terapéutico , Adenosina Difosfato/metabolismo , Adulto , Anemia de Células Falciformes/metabolismo , Biomarcadores/metabolismo , Plaquetas/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Clorhidrato de Prasugrel , Adulto Joven
12.
Eur J Haematol ; 92(3): 249-55, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24329965

RESUMEN

The study's objective was to assess the cost-effectiveness of preoperative transfusion compared with no preoperative transfusion in patients with sickle cell disease undergoing low- or medium-risk surgery. Seventy patients with sickle cell disease (HbSS/Sß(0) thal genotypes) undergoing elective surgery participated in a multicentre randomised trial, Transfusion Alternatives Preoperatively in Sickle Cell Disease (TAPS). Here, a cost-effectiveness analysis based on evidence from that trial is presented. A decision-analytic model is used to incorporate long-term consequences of transfusions and acute chest syndrome. Costs and health benefits, expressed as quality-adjusted life years (QALYs), are reported from the 'within-trial' analysis and for the decision-analytic model. The probability of cost-effectiveness for each form of management is calculated taking into account the small sample size and other sources of uncertainty. In the range of scenarios considered in the analysis, preoperative transfusion was more effective, with the mean improvement in QALYs ranging from 0.018 to 0.206 per patient, and also less costly in all but one scenario, with the mean cost difference ranging from -£813 to £26. All scenarios suggested preoperative transfusion had a probability of cost-effectiveness >0.79 at a cost-effectiveness threshold of £20 000 per QALY.


Asunto(s)
Anemia de Células Falciformes/economía , Anemia de Células Falciformes/terapia , Transfusión Sanguínea/economía , Anciano , Algoritmos , Análisis Costo-Beneficio , Técnicas de Apoyo para la Decisión , Femenino , Costos de la Atención en Salud , Humanos , Masculino , Persona de Mediana Edad , Años de Vida Ajustados por Calidad de Vida , Resultado del Tratamiento
13.
Lancet ; 381(9870): 930-8, 2013 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-23352054

RESUMEN

BACKGROUND: No consensus exists on whether preoperative blood transfusions are beneficial in patients with sickle-cell disease. We assessed whether perioperative complication rates would be altered by preoperative transfusion. METHODS: We did a multicentre, randomised trial. Eligible patients were aged at least 1 year, had haemoglobin SS or Sß(0)thalassaemia sickle-cell-disease subtypes, and were scheduled for low-risk or medium-risk operations. Patients were randomly assigned no transfusion or transfusion no more than 10 days before surgery. The primary outcome was the proportion of clinically important complications between randomisation and 30 days after surgery. Analysis was by intention to treat. FINDINGS: 67 (96%) of 70 enrolled patients-33 no preoperative transfusion and 34 preoperative transfusion-were assessed. 65 (97%) of 67 patients had the haemoglobin SS subtype and 54 (81%) were scheduled to undergo medium-risk surgery. 13 (39%) of 33 patients in the no-preoperative-transfusion group had clinically important complications, compared with five (15%) in the preoperative-transfusion group (p=0.023). Of these, 10 (30%) and one (3%), respectively, had serious adverse events. The unadjusted odds ratio of clinically important complications was 3.8 (95% CI 1.2-12.2, p=0.027). 10 (91%) of 11 serious adverse events were acute chest syndrome (nine in the no-preoperative-transfusion group and one in the preoperative-transfusion group). Duration of hospital stay and readmission rates did not differ between study groups. INTERPRETATION: Preoperative transfusion was associated with decreased perioperative complications in patients with sickle-cell disease in this trial. This approach could, therefore, be beneficial for patients with the haemoglobin SS subtype who are scheduled to undergo low-risk and medium-risk surgeries. FUNDING: NHS Blood and Transplant.


Asunto(s)
Síndrome Torácico Agudo/prevención & control , Anemia de Células Falciformes/terapia , Transfusión Sanguínea , Hemoglobina Falciforme/metabolismo , Complicaciones Posoperatorias/prevención & control , Procedimientos Quirúrgicos Operativos , Síndrome Torácico Agudo/etiología , Adolescente , Adulto , Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/complicaciones , Canadá , Niño , Preescolar , Europa (Continente) , Femenino , Humanos , Lactante , Masculino , Oportunidad Relativa , Periodo Perioperatorio , Procedimientos Quirúrgicos Operativos/efectos adversos , Resultado del Tratamiento , Talasemia beta/terapia
14.
Br J Clin Pharmacol ; 75(6): 1433-44, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23171128

RESUMEN

AIMS: Prasugrel is a novel thienopyridine P2Y12 adenosine diphosphate (ADP) receptor antagonist that inhibits ADP-mediated platelet activation and aggregation. Accordingly, it may be useful in reducing platelet-related ischaemia in sickle cell disease (SCD). Exposure to prasugrel's active metabolite (Pras-AM) and its antiplatelet activity in SCD have not been investigated. METHODS: Thirteen adult patients with SCD and an equal number of matched healthy control subjects were studied before and after 12 days of 5.0 or 7.5 mg day(-1) prasugrel treatment. Platelet reactivity was assessed by light transmission aggregometry (LTA), impedance aggregometry (MEA), VerifyNow® P2Y12, vasodilator-stimulated phosphoprotein (VASP) phosphorylation and Plateletworks. Exposure to Pras-AM was also assessed. RESULTS: At baseline, patients with SCD showed increased platelet reactivity vs. healthy control subjects with VerifyNow (408 vs. 323 P2Y12 reaction units (PRU), respectively, P = 0.003) and MEA (106 vs. 77 area under the aggregation curve (AU.min), P = 0.002); lower platelet reactivity index with VASP flow cytometry (59 vs. 79% platelet reactivity index (PRI), P = 0.018); and no significant differences with LTA, VASP enzyme-linked immunosorbent assay or Plateletworks. Relative to baseline, prasugrel significantly reduced platelet reactivity by all assays in both populations (all P < 0.05). Prasugrel was well tolerated, with no bleeding-related events in patients with SCD. The mean concentration-time profiles of Pras-AM were comparable between healthy subjects and patients with SCD following a single 10 mg prasugrel dose and following the 12th dose of 7.5 or 5 mg prasugrel. CONCLUSIONS: Results demonstrate that in response to prasugrel, patients with SCD and healthy subjects have similar degrees of platelet inhibition and exposure to Pras-AM, and provide a basis for further study of prasugrel in patients with SCD.


Asunto(s)
Anemia de Células Falciformes/metabolismo , Plaquetas/efectos de los fármacos , Piperazinas/farmacocinética , Antagonistas del Receptor Purinérgico P2/farmacocinética , Tiofenos/farmacocinética , Adulto , Anemia de Células Falciformes/tratamiento farmacológico , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Humanos , Masculino , Piperazinas/efectos adversos , Piperazinas/farmacología , Pruebas de Función Plaquetaria , Clorhidrato de Prasugrel , Antagonistas del Receptor Purinérgico P2/efectos adversos , Antagonistas del Receptor Purinérgico P2/farmacología , Tiofenos/efectos adversos , Tiofenos/farmacología , Adulto Joven
15.
Theriogenology ; 66(6-7): 1768-77, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16513161

RESUMEN

In many species, controlling the ovary prior to induction of ovulation improves the success of ovarian response and artificial insemination (AI). We assessed the impact of suppression of estrus with the GnRH agonist, Lupron, on ovarian sensitivity to equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG) in the clouded leopard. Seven female clouded leopards were given two injections of Lupron (3.75 mg IM) 23 d apart, followed 44 d later by eCG and hCG. Daily fecal samples were collected from 60 d before Lupron to 60 d after hCG. Fecal metabolites of estrogen (E) and progesterone (P) were measured by radioimmunoassay. Lupron decreased (P < 0.05) the number of E peaks during Lupron treatment compared to pre-Lupron. All females had baseline E and six of seven (86%) had nadir P on day of eCG. Exogenous gonadotropins induced E elevations in all females. However, mean E in the gonadotropin-provoked estrus was decreased (P < 0.05) compared to pre-Lupron estrous periods. Only one of seven (14%) females ovulated after eCG/hCG. In conclusion, estrous cycle control with Lupron resulted in predictable ovarian suppression prior to gonadotropin stimulation but altered ovarian sensitivity by an as yet unknown mechanism so that ovulation was inhibited, even when using a proven exogenous gonadotropin protocol.


Asunto(s)
Ciclo Estral/efectos de los fármacos , Felidae/fisiología , Fármacos para la Fertilidad Femenina/farmacología , Gonadotropinas Equinas/farmacología , Leuprolida/farmacología , Inhibición de la Ovulación/efectos de los fármacos , Animales , Animales de Zoológico , Estrógenos/metabolismo , Ciclo Estral/fisiología , Heces/química , Femenino , Progesterona/metabolismo
16.
Br J Haematol ; 131(1): 123-8, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16173972

RESUMEN

Cannabinoids are increasingly being considered for the management of various painful conditions, and could be considered as an option for treating acute pain in sickle cell disease (SCD). The objective of this study was to determine the extent of use of cannabis in the community for pain and other symptom relief, and its side effects during self-administration in patients with SCD. Patients attending Central Middlesex Hospital in London were invited to complete a structured self-administered anonymous questionnaire. Eighty-six young adults with HbSS, HbSC and HbSbetathalassaemia disease (median age 30 years) participated in the study. Results showed that 31 (36%) had used cannabis in the previous 12 months to relieve symptoms associated with SCD. The main route in all but two patients was by smoking. The main reasons for use were to reduce pain in 52%, and to induce relaxation or relieve anxiety and depression in 39%. Symptoms related to sedation and mood effects were reported in 77% of patients. The majority of patients (58%) expressed their willingness to participate in studies of cannabis as a medicine. We conclude that research in the use of cannabinoids for pain relief in SCD would be both important and acceptable to adult patients.


Asunto(s)
Anemia de Células Falciformes/tratamiento farmacológico , Cannabaceae , Fitoterapia/métodos , Enfermedad Aguda , Adulto , Anemia de Células Falciformes/psicología , Femenino , Humanos , Masculino , Abuso de Marihuana/psicología , Dolor/tratamiento farmacológico , Autoadministración , Encuestas y Cuestionarios
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