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1.
Blood Adv ; 8(3): 746-757, 2024 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-38181780

RESUMEN

ABSTRACT: Advancements in orally bioavailable iron chelators and MRI methods have improved life expectancy and reproductive potential in thalassemia major (TM) and thalassemia intermedia (TI). Pregnancy is associated with adverse maternal and neonatal outcomes, frequency of which has not been well delineated. This systematic review aims to provide risk estimates of maternal and fetal outcomes in TM and TI and explore pregnancy's impact on iron homeostasis. Fifteen studies (429 participants, 684 pregnancies) were included. Meta-analysis revealed a higher thrombosis risk in TI (3.7%) compared to TM (0.92%), unchanged from prepregnancy. Heart failure risks in the earlier years appeared similar (TM 1.6% vs TI 1.1%), and maternal mortality in TM was 3.7%, but with current management, these risks are rare. Gestational diabetes and pre-eclampsia occurred in 3.9% and 11.3% of TM pregnancies, respectively. Caesarean section rates were 83.9% in TM and 67% in TI. No significant difference in stillbirth, small for gestational age neonates, or preterm birth incidence between TM and TI was observed. In TM pregnancies, red cell requirements significantly increased (from 102 to 139 ml/kg/year, P = 0.001), and 70% of TI pregnancies required blood transfusions. As expected, increased transfusion alongside chelation cessation led to a significant increase in serum ferritin during pregnancy (TM by 1005 ng/mL; TI by 332 ng/mL, P < 0.0001). Deterioration in iron status was further reflected by an increase in liver iron concentration (from 4.6 to 11.9 mg/g dry weight, P < 0.0001), and myocardial T2-star (T2∗) magnetic resonance imaging decreased (from 36.2 ± 2.5 ms to 31.1 ms) during pregnancy. These findings emphasize the elevated maternal risk of iron-related cardiomyopathy during pregnancy and labor, stressing the importance of cardiac monitoring and postpartum chelation therapy resumption.


Asunto(s)
Nacimiento Prematuro , Talasemia beta , Humanos , Recién Nacido , Embarazo , Femenino , Talasemia beta/complicaciones , Talasemia beta/terapia , Hierro , Resultado del Embarazo , Cesárea
2.
Nat Hum Behav ; 8(4): 779-793, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38182882

RESUMEN

Despite its crucial role in the regulation of vital metabolic and neurological functions, the genetic architecture of the hypothalamus remains unknown. Here we conducted multivariate genome-wide association studies (GWAS) using hypothalamic imaging data from 32,956 individuals to uncover the genetic underpinnings of the hypothalamus and its involvement in neuropsychiatric traits. There were 23 significant loci associated with the whole hypothalamus and its subunits, with functional enrichment for genes involved in intracellular trafficking systems and metabolic processes of steroid-related compounds. The hypothalamus exhibited substantial genetic associations with limbic system structures and neuropsychiatric traits including chronotype, risky behaviour, cognition, satiety and sympathetic-parasympathetic activity. The strongest signal in the primary GWAS, the ADAMTS8 locus, was replicated in three independent datasets (N = 1,685-4,321) and was strengthened after meta-analysis. Exome-wide association analyses added evidence to the association for ADAMTS8, and Mendelian randomization showed lower ADAMTS8 expression with larger hypothalamic volumes. The current study advances our understanding of complex structure-function relationships of the hypothalamus and provides insights into the molecular mechanisms that underlie hypothalamic formation.


Asunto(s)
Estudio de Asociación del Genoma Completo , Hipotálamo , Humanos , Hipotálamo/metabolismo , Hipotálamo/diagnóstico por imagen , Masculino , Femenino , Adulto , Trastornos Mentales/genética , Proteínas ADAMTS/genética , Persona de Mediana Edad , Análisis de la Aleatorización Mendeliana
3.
Blood Rev ; 64: 101165, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38182489

RESUMEN

α-Thalassemia is an inherited blood disorder characterized by decreased synthesis of α-globin chains that results in an imbalance of α and ß globin and thus varying degrees of ineffective erythropoiesis, decreased red blood cell (RBC) survival, chronic hemolytic anemia, and subsequent comorbidities. Clinical presentation varies depending on the genotype, ranging from a silent or mild carrier state to severe, transfusion-dependent or lethal disease. Management of patients with α-thalassemia is primarily supportive, addressing either symptoms (eg, RBC transfusions for anemia), complications of the disease, or its transfusion-dependence (eg, chelation therapy for iron overload). Several novel therapies are also in development, including curative gene manipulation techniques and disease modifying agents that target ineffective erythropoiesis and chronic hemolytic anemia. This review of α-thalassemia and its various manifestations provides practical information for clinicians who practice beyond those regions where it is found with high frequency.


Asunto(s)
Enfermedades Hematológicas , Sobrecarga de Hierro , Talasemia alfa , Talasemia beta , Humanos , Talasemia beta/terapia , Talasemia alfa/diagnóstico , Talasemia alfa/genética , Talasemia alfa/terapia , Eritropoyesis , Transfusión de Eritrocitos , Sobrecarga de Hierro/diagnóstico , Sobrecarga de Hierro/etiología , Sobrecarga de Hierro/terapia
4.
Eur Radiol ; 31(12): 9296-9305, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34041571

RESUMEN

OBJECTIVES: MRI quantification of liver iron concentration (LIC) using R2 or R2* relaxometry requires offline post-processing causing reporting delays, administrative overhead, and added costs. A prototype 3D multi-gradient-echo pulse sequence, with inline post-processing, allows immediate calculation of LIC from an R2* map (inline R2*-LIC) without offline processing. We compared inline R2*-LIC to FerriScan and offline R2* calibration methods. METHODS: Forty patients (25 women, 15 men; age 18-82 years), prospectively underwent FerriScan and the prototype sequence, which produces two R2* maps, with and without fat modeling, as well as an inline R2*-LIC map derived from the R2* map with fat modeling, with informed consent. For each map, the following contours were drawn: ROIs, whole-axial-liver contour, and an exact copy of contour utilized by FerriScan. LIC values from the FerriScan report and those calculated using an alternative R2 calibration were the reference standards. Results were compared using Pearson and interclass correlation coefficients (PCC, ICC), linear regression, Bland-Altman analysis, and estimation of area under the receiver operator curve (ROC-AUC). RESULTS: Inline R2*-LIC demonstrated good agreement with the reference standards. Compared to FerriScan, inline R2*-LIC with whole-axial-liver contour, ROIs, and FerriScan contour demonstrated PCC of 94.8%, 94.8%, and 92%; ICC 93%, 92.7%, and 90.2%; regression slopes 1.004, 0.974, and 1.031; mean bias 5.54%, 10.91%, and 0.36%; and ROC-AUC estimates 0.903, 0.906, and 0.890 respectively. Agreement was maintained when adjusted for sex, age, diagnosis, liver fat content, and fat-water swap. CONCLUSION: Inline R2*-LIC provides robust and comparable quantification of LIC compared to FerriScan, without the need for offline post-processing. KEY POINTS: • In patients being treated for iron overload with chelation therapy, liver iron concentration (LIC) is regularly assessed in order to monitor and adjust therapy. • Magnetic resonance imaging (MRI) is commonly used to quantify LIC. Several R2 and R2* methods are available, all of which require offline post-processing. • A novel R2* MRI method allows for immediate calculation of LIC and provides comparable quantification of LIC to the FerriScan and recently published alternative R2* methods.


Asunto(s)
Sobrecarga de Hierro , Hierro , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Terapia por Quelación , Femenino , Humanos , Sobrecarga de Hierro/diagnóstico por imagen , Sobrecarga de Hierro/tratamiento farmacológico , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Adulto Joven
5.
Blood ; 131(20): 2183-2192, 2018 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-29549173

RESUMEN

An international, multicenter registry was established to collect retrospective and prospective clinical data on patients with pyruvate kinase (PK) deficiency, the most common glycolytic defect causing congenital nonspherocytic hemolytic anemia. Medical history and laboratory and radiologic data were retrospectively collected at enrollment for 254 patients with molecularly confirmed PK deficiency. Perinatal complications were common, including anemia that required transfusions, hyperbilirubinemia, hydrops, and prematurity. Nearly all newborns were treated with phototherapy (93%), and many were treated with exchange transfusions (46%). Children age 5 years and younger were often transfused until splenectomy. Splenectomy (150 [59%] of 254 patients) was associated with a median increase in hemoglobin of 1.6 g/dL and a decreased transfusion burden in 90% of patients. Predictors of a response to splenectomy included higher presplenectomy hemoglobin (P = .007), lower indirect bilirubin (P = .005), and missense PKLR mutations (P = .0017). Postsplenectomy thrombosis was reported in 11% of patients. The most frequent complications included iron overload (48%) and gallstones (45%), but other complications such as aplastic crises, osteopenia/bone fragility, extramedullary hematopoiesis, postsplenectomy sepsis, pulmonary hypertension, and leg ulcers were not uncommon. Overall, 87 (34%) of 254 patients had both a splenectomy and cholecystectomy. In those who had a splenectomy without simultaneous cholecystectomy, 48% later required a cholecystectomy. Although the risk of complications increases with severity of anemia and a genotype-phenotype relationship was observed, complications were common in all patients with PK deficiency. Diagnostic testing for PK deficiency should be considered in patients with apparent congenital hemolytic anemia and close monitoring for iron overload, gallstones, and other complications is needed regardless of baseline hemoglobin. This trial was registered at www.clinicaltrials.gov as #NCT02053480.


Asunto(s)
Anemia Hemolítica Congénita no Esferocítica/diagnóstico , Estudios de Asociación Genética , Piruvato Quinasa/deficiencia , Errores Innatos del Metabolismo del Piruvato/diagnóstico , Adolescente , Adulto , Anemia Hemolítica Congénita no Esferocítica/etiología , Anemia Hemolítica Congénita no Esferocítica/metabolismo , Anemia Hemolítica Congénita no Esferocítica/terapia , Transfusión Sanguínea , Niño , Preescolar , Colecistectomía/efectos adversos , Colecistectomía/métodos , Terapia Combinada , Activación Enzimática , Femenino , Genotipo , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Mutación , Fenotipo , Piruvato Quinasa/metabolismo , Errores Innatos del Metabolismo del Piruvato/etiología , Errores Innatos del Metabolismo del Piruvato/metabolismo , Errores Innatos del Metabolismo del Piruvato/terapia , Esplenectomía/efectos adversos , Esplenectomía/métodos , Evaluación de Síntomas , Resultado del Tratamiento , Adulto Joven
6.
Am J Hematol ; 92(12): 1356-1361, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28940308

RESUMEN

Our phase I, open-label, multi-center, dose-escalation study evaluated the pharmacokinetics (PK) of SP-420, a tridentate oral iron chelating agent of the desferrithiocin class, in patients with transfusion dependent ß-thalassemia. SP-420 was administered as a single dose of 1.5 (n = 3), 3 (n = 3), 6 (n = 3), 12 (n = 3), and 24 (n = 6) mg/kg or as a twice-daily dose of 9 mg/kg (n = 6) over 14-28 days. There was a near dose-linear increase in the mean plasma SP-420 concentrations and in the mean values for Cmax and AUC0-τ over the dose range evaluated. The median tmax ranged from 0.5 to 2.25 h and was not dose dependent. The study was prematurely terminated by the sponsor due to renal adverse events (AE) including proteinuria, increase in serum creatinine, and one case of Fanconi syndrome. Other adverse effects included hypersensitivity reactions and gastrointestinal disturbances. Based on current dose administration, the renal AE observed outweighed the possible benefits from chelation therapy. However, additional studies assessing efficacy and safety of lower doses or less frequent dosing of SP-420 over longer durations with close monitoring would be necessary to better explain the findings of our study and characterize the safety of the study drug.


Asunto(s)
Ciclohexanonas/farmacocinética , Dihidropiridinas/efectos adversos , Quelantes del Hierro/efectos adversos , Quelantes del Hierro/farmacocinética , Tiazoles/efectos adversos , Tiazoles/farmacocinética , Talasemia beta/terapia , Adolescente , Adulto , Transfusión Sanguínea , Ciclohexanonas/efectos adversos , Ciclohexanonas/uso terapéutico , Dihidropiridinas/uso terapéutico , Relación Dosis-Respuesta a Droga , Humanos , Quelantes del Hierro/administración & dosificación , Enfermedades Renales/inducido químicamente , Persona de Mediana Edad , Sideróforos/uso terapéutico , Sideróforos/toxicidad , Tiazoles/uso terapéutico , Adulto Joven , Talasemia beta/complicaciones , Talasemia beta/tratamiento farmacológico
7.
Proc Natl Acad Sci U S A ; 110(16): 6448-52, 2013 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-23576718

RESUMEN

In 2011, Lake Erie experienced the largest harmful algal bloom in its recorded history, with a peak intensity over three times greater than any previously observed bloom. Here we show that long-term trends in agricultural practices are consistent with increasing phosphorus loading to the western basin of the lake, and that these trends, coupled with meteorological conditions in spring 2011, produced record-breaking nutrient loads. An extended period of weak lake circulation then led to abnormally long residence times that incubated the bloom, and warm and quiescent conditions after bloom onset allowed algae to remain near the top of the water column and prevented flushing of nutrients from the system. We further find that all of these factors are consistent with expected future conditions. If a scientifically guided management plan to mitigate these impacts is not implemented, we can therefore expect this bloom to be a harbinger of future blooms in Lake Erie.


Asunto(s)
Cambio Climático , Eutrofización/fisiología , Lagos/microbiología , Modelos Biológicos , Fósforo/análisis , Contaminantes Químicos del Agua/análisis , Agricultura/métodos , Conservación de los Recursos Naturales/métodos , Great Lakes Region , Lagos/análisis , Lluvia , Temperatura , Movimientos del Agua , Viento
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