RESUMEN
The VH1-2 restricted VRC01-class of antibodies targeting the HIV envelope CD4 binding site are a major focus of HIV vaccine strategies. However, a detailed analysis of VRC01-class antibody development has been limited by the rare nature of these responses during natural infection and the lack of longitudinal sampling of such responses. To inform vaccine strategies, we mapped the development of a VRC01-class antibody lineage (PCIN63) in the subtype C infected IAVI Protocol C neutralizer PC063. PCIN63 monoclonal antibodies had the hallmark VRC01-class features and demonstrated neutralization breadth similar to the prototype VRC01 antibody, but were 2- to 3-fold less mutated. Maturation occurred rapidly within â¼24 months of emergence of the lineage and somatic hypermutations accumulated at key contact residues. This longitudinal study of broadly neutralizing VRC01-class antibody lineage reveals early binding to the N276-glycan during affinity maturation, which may have implications for vaccine design.
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Vacunas contra el SIDA/inmunología , Anticuerpos Monoclonales/metabolismo , Anticuerpos Neutralizantes/metabolismo , Anticuerpos ampliamente neutralizantes/metabolismo , Anticuerpos Anti-VIH/metabolismo , Infecciones por VIH/inmunología , VIH-1/fisiología , Vacunas contra el SIDA/genética , Secuencia de Aminoácidos , Anticuerpos Monoclonales/genética , Anticuerpos Neutralizantes/genética , Afinidad de Anticuerpos , Linfocitos B/inmunología , Anticuerpos ampliamente neutralizantes/genética , Antígenos CD4/metabolismo , Regiones Determinantes de Complementariedad/genética , Anticuerpos Anti-VIH/genética , Proteína gp120 de Envoltorio del VIH/inmunología , Proteína gp120 de Envoltorio del VIH/metabolismo , Humanos , Polisacáridos/metabolismo , Unión ProteicaRESUMEN
Mastocytosis is a heterogeneous group of disorders comprising cutaneous mastocytosis, systemic mastocytosis, and mast cell sarcoma. It is associated with a variety of symptoms related to the release of mast cell mediators and mast cell tissue infiltration. Referral to specialized centers with expertise in the management of mastocytosis and multidisciplinary collaboration with subspecialists (eg, allergists for the management of anaphylaxis and drug hypersensitivities, anesthesiologists for invasive procedures or surgery, high-risk obstetrician for pregnancy) is recommended. The NCCN Guidelines for Systemic Mastocytosis provide evidence- and consensus-based recommendations for the diagnosis and comprehensive care of patients with systemic mastocytosis. The multidisciplinary panel of experts convenes at least once a year to review requested changes to the guidelines from both internal and external entities as well as to discuss data on existing and new therapies. These NCCN Guidelines Insights focus on some of the recent updates to the guidelines.
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Mastocitosis Sistémica , Humanos , Mastocitosis Sistémica/diagnóstico , Mastocitosis Sistémica/terapia , Manejo de la Enfermedad , Oncología Médica/normas , Oncología Médica/métodosRESUMEN
Chronic myeloid leukemia (CML) is defined by the presence of Philadelphia chromosome resulting from a reciprocal translocation between chromosomes 9 and 22 [t9;22] that gives rise to a BCR::ABL1 fusion gene. CML occurs in 3 different phases (chronic, accelerated, and blast phase) and is usually diagnosed in the chronic phase in developed countries. Tyrosine kinase inhibitor (TKI) therapy is a highly effective treatment option for patients with chronic phase-CML. The primary goal of TKI therapy in patients with chronic phase-CML is to prevent disease progression to accelerated phase-CML or blast phase-CML. Discontinuation of TKI therapy with careful monitoring is feasible in selected patients. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with chronic phase-CML.
Asunto(s)
Leucemia Mielógena Crónica BCR-ABL Positiva , Leucemia Mieloide de Fase Crónica , Humanos , Crisis Blástica/inducido químicamente , Crisis Blástica/tratamiento farmacológico , Crisis Blástica/genética , Inhibidores de Proteínas Quinasas/efectos adversos , Leucemia Mielógena Crónica BCR-ABL Positiva/diagnóstico , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Cromosoma Filadelfia , Leucemia Mieloide de Fase Crónica/tratamiento farmacológico , Proteínas de Fusión bcr-abl/genéticaRESUMEN
Eosinophilic phenotypes in polycythemia vera (PV) and essential thrombocythemia (ET) are rare and poorly characterized. Co-occurring JAK2 mutations in cis, specifically L611S or N622Y mutations, appear to result in a more aggressive clinical phenotype. PV/ET with eosinophilic phenotypes may require full next-generation sequencing to capture co-occurring mutations as opposed to more prevalent single-gene assays. These eosinophilic phenotypes are highly thrombotic and systemic symptoms appear responsive to early use of the janus kinase inhibitor ruxolitinib.
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Eosinofilia , Policitemia Vera , Trombocitemia Esencial , Humanos , Policitemia Vera/diagnóstico , Policitemia Vera/genética , Mutación , Trombocitemia Esencial/genética , Eosinofilia/genética , Fenotipo , Exones , Janus Quinasa 2/genéticaRESUMEN
The classic Philadelphia chromosome-negative myeloproliferative neoplasms (MPN) consist of myelofibrosis, polycythemia vera, and essential thrombocythemia and are a heterogeneous group of clonal blood disorders characterized by an overproduction of blood cells. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for MPN were developed as a result of meetings convened by a multidisciplinary panel with expertise in MPN, with the goal of providing recommendations for the management of MPN in adults. The Guidelines include recommendations for the diagnostic workup, risk stratification, treatment, and supportive care strategies for the management of myelofibrosis, polycythemia vera, and essential thrombocythemia. Assessment of symptoms at baseline and monitoring of symptom status during the course of treatment is recommended for all patients. This article focuses on the recommendations as outlined in the NCCN Guidelines for the diagnosis of MPN and the risk stratification, management, and supportive care relevant to MF.
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Trastornos Mieloproliferativos , Policitemia Vera , Mielofibrosis Primaria , Trombocitemia Esencial , Adulto , Humanos , Oncología Médica , Trastornos Mieloproliferativos/diagnóstico , Trastornos Mieloproliferativos/terapia , Policitemia Vera/diagnóstico , Mielofibrosis Primaria/diagnóstico , Trombocitemia Esencial/diagnósticoRESUMEN
Patients with myelofibrosis (MF) who discontinue ruxolitinib due to progression/resistance have poor prognoses. JAK inhibitors control symptoms and reduce spleen volumes with limited impact on underlying disease pathophysiology. Murine double minute 2 (MDM2), a negative regulator of p53, is overexpressed in circulating malignant CD34+ MF cells. The oral MDM2 inhibitor navtemadlin (KRT-232) restores p53 activity to drive apoptosis of wild-type TP53 tumor cells by inducing expression of pro-apoptotic Bcl-2 family proteins. Navtemadlin demonstrated promising clinical and disease-modifying activity and acceptable safety in a phase II study in patients with relapsed/refractory MF. The randomized phase III BOREAS study compares the efficacy and safety of navtemadlin to best available therapy in patients with MF that is relapsed/refractory to JAK inhibitor treatment.
Myelofibrosis (MF) is a rare blood cancer that disrupts normal blood cell production and causes fibrosis (tissue thickening/scarring) in bone marrow, reduced red blood cells in the circulation, and an enlarged spleen. Although currently approved treatments can help relieve some effects, they have limited impact on the underlying cause of the disease. Navtemadlin is a new therapy that inhibits a protein frequently overexpressed in cancer cells found in MF patients called murine double minute 2 (MDM2), which regulates a common tumor suppressor protein called p53. By inhibiting MDM2, navtemadlin restores normal p53 function and its ability to kill MF cancer cells. BOREAS is a large clinical study of navtemadlin for MF patients whose disease is not responding to current therapy.
RESUMEN
INTRODUCTION: Novel long-acting lipoglycopeptide antibiotics allow for the treatment and discharge of selected emergency department (ED) patients with cellulitis who require intravenous antibiotics. Telehealth systems have shown success in remote management of dermatologic conditions; we implemented a telehealth follow-up program for patients diagnosed with cellulitis in the ED, treated with single-dose dalbavancin, and discharged. METHODS: This was a prospective, multi-center observational study. Patients were included based on clinical criteria and ability to complete follow-up using a smartphone and enroll in an online care portal. We examined the rate of successful telehealth follow-up at 24- and 72-hour intervals from discharge. We also examined the ED return rate within 14 days, reviewed any visits to determine cause of return, and for admission. RESULTS: 55 patients were enrolled. 54/55 patients completed at least one telehealth follow up encounter (98.2%). 13 patients (23.6%) had a return ED visit within 14 days; no patients required admission for worsening cellulitis. Patient engagement in the telehealth program decreased over time; there was an approximately 11% decrease in engagement between the 24 and 72-hour follow-up call, and a 15% decrease in engagement between the 24 and 72-hour image upload. Patients over 65 had a lower rate of image upload (31%) than younger patients (80.6%). DISCUSSION: A telehealth follow-up system for discharged emergency department patients with cellulitis demonstrated high rates of engagement. In these patients who -may have otherwise required admission for intravenous antibiotics, telehealth-facilitated outpatient management resulted in a low ED return rate and no inpatient admissions for cellulitis.
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Antibacterianos/administración & dosificación , Celulitis (Flemón)/tratamiento farmacológico , Servicio de Urgencia en Hospital , Alta del Paciente , Teicoplanina/análogos & derivados , Telemedicina/métodos , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Teicoplanina/administración & dosificaciónRESUMEN
Long-read next-generation amplicon sequencing shows promise for studying complete genes or genomes from complex and diverse populations. Current long-read sequencing technologies have challenging error profiles, hindering data processing and incorporation into downstream analyses. Here we consider the problem of how to reconstruct, free of sequencing error, the true sequence variants and their associated frequencies from PacBio reads. Called 'amplicon denoising', this problem has been extensively studied for short-read sequencing technologies, but current solutions do not always successfully generalize to long reads with high indel error rates. We introduce two methods: one that runs nearly instantly and is very accurate for medium length reads and high template coverage, and another, slower method that is more robust when reads are very long or coverage is lower. On two Mock Virus Community datasets with ground truth, each sequenced on a different PacBio instrument, and on a number of simulated datasets, we compare our two approaches to each other and to existing algorithms. We outperform all tested methods in accuracy, with competitive run times even for our slower method, successfully discriminating templates that differ by a just single nucleotide. Julia implementations of Fast Amplicon Denoising (FAD) and Robust Amplicon Denoising (RAD), and a webserver interface, are freely available.
Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Metagenómica , ARN Ribosómico 16S/genética , Virus/genética , Algoritmos , Técnicas de Visualización de Superficie Celular/métodos , VIH/genética , Filogenia , Alineación de Secuencia , Anticuerpos de Cadena Única/genética , Programas InformáticosRESUMEN
BACKGROUND: Diphenhydramine, a first generation H1 histamine receptor antagonist, is a commonly used nonprescription medication that is used for the treatment of allergy, as a sleep aid, or combined with cough and cold remedies. Naproxen, a nonsteroidal anti-inflammatory drug (NSAID), is used commonly for analgesia. Although most cases of diphenhydramine or naproxen overdose require excellent supportive care only, meticulous attention should be given to cardiovascular and neurologic status. CASE REPORT: A 22-year-old woman presented with altered mental status secondary to intentional ingestion of 240 combination caplets of naproxen sodium 220 mg and diphenhydramine hydrochloride 25 mg. While in the emergency department, she manifested a wide-complex tachycardia in the setting of hypotension that required repeated administration of sodium bicarbonate to overcome the sodium channel blockade caused by diphenhydramine. Aggressive potassium repletion was performed simultaneously. Her clinical course was complicated by status-epilepticus that required intubation. Orogastric lavage was performed, which returned blue pill slurry consistent with the ingested caplets. The patient was extubated on hospital day 2 and transferred to psychiatry thereafter. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: In light of recent social media trends, such as the "Benadryl challenge" and its widespread availability, emergency providers should be familiar with diphenhydramine toxicity, especially the life-threatening neurologic consequences and risk of cardiovascular collapse. NSAIDs, such as naproxen, and other nonprescription analgesics are becoming more and more important in light of the current opioid crisis. There should be an emphasis on understanding these medications and their potential implications when taken in overdose.
Asunto(s)
Difenhidramina , Sobredosis de Droga , Difenhidramina/uso terapéutico , Sobredosis de Droga/tratamiento farmacológico , Femenino , Humanos , Naproxeno/efectos adversos , Bicarbonato de Sodio/uso terapéutico , Taquicardia , Adulto JovenRESUMEN
Chronic myeloid leukemia (CML) is defined by the presence of Philadelphia chromosome (Ph) which results from a reciprocal translocation between chromosomes 9 and 22 [t(9;22] that gives rise to a BCR-ABL1 fusion gene. CML occurs in 3 different phases (chronic, accelerated, and blast phase) and is usually diagnosed in the chronic phase. Tyrosine kinase inhibitor therapy is a highly effective first-line treatment option for all patients with newly diagnosed chronic phase CML. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with chronic phase CML.
Asunto(s)
Leucemia Mielógena Crónica BCR-ABL Positiva , Leucemia Mieloide de Fase Crónica , Proteínas de Fusión bcr-abl/genética , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/diagnóstico , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Oncología Médica , Cromosoma Filadelfia , Translocación GenéticaRESUMEN
Eosinophilic disorders and related syndromes represent a heterogeneous group of neoplastic and nonneoplastic conditions, characterized by more eosinophils in the peripheral blood, and may involve eosinophil-induced organ damage. In the WHO classification of myeloid and lymphoid neoplasms, eosinophilic disorders characterized by dysregulated tyrosine kinase (TK) fusion genes are recognized as a new category termed, myeloid/lymphoid neoplasms with eosinophilia and rearrangement of PDGFRA, PDGFRB or FGFR1 or with PCM1-JAK2. In addition to these aforementioned TK fusion genes, rearrangements involving FLT3 and ABL1 genes have also been described. These new NCCN Guidelines include recommendations for the diagnosis, staging, and treatment of any one of the myeloid/lymphoid neoplasms with eosinophilia (MLN-Eo) and a TK fusion gene included in the 2017 WHO Classification, as well as MLN-Eo and a FLT3 or ABL1 rearrangement.
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Eosinofilia , Trastornos Mieloproliferativos , Neoplasias , Eosinofilia/diagnóstico , Eosinofilia/genética , Humanos , Trastornos Mieloproliferativos/diagnóstico , Trastornos Mieloproliferativos/genética , Trastornos Mieloproliferativos/terapia , Proteínas de Fusión Oncogénica/genéticaRESUMEN
For patients with high risk myeloid disease, allogeneic hematopoietic cell transplantation (HCT) is the only potentially curative therapy. Unfortunately, many of these patients relapse after HCT and have a limited survival. The recent approval of venetoclax, an orally bioavailable BCL-2 inhibitor, resulted in significant responses in treatment naïve acute myeloid leukemia (AML), and off-label use in the relapsed/refractory setting is increasing. We report the outcomes of 21 patients who underwent allogeneic HCT for myeloid disease, relapsed with AML, and were treated with venetoclax. Several patients had poor risk features including antecedent hematologic malignancy (6/21), complex karyotype (6/21), and TP53 mutations (5/21). The median age was 64.5 years and time from HCT to relapse was 5.7 months (range: 0.9 to 44.9 months). Of the 19 patients who were assessed for response, there were meaningful treatment responses seen in eight patients: five CR, three CRi, zero PR, for an ORR of 42.1%. Treatment effect was seen in six additional patients, including four in the morphologic leukemia-free state. Nine patients maintained their response for ≥3 months and eight were receiving therapy at data cut. Post-HCT AML relapse has an exceedingly poor outcome, and venetoclax-based therapy is a potent therapy option that should be studied prospectively in this setting.
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Compuestos Bicíclicos Heterocíclicos con Puentes/administración & dosificación , Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Terapia Recuperativa , Sulfonamidas/administración & dosificación , Adulto , Anciano , Aloinjertos , Supervivencia sin Enfermedad , Femenino , Humanos , Leucemia Mieloide Aguda/mortalidad , Leucemia Mieloide Aguda/terapia , Masculino , Persona de Mediana Edad , Tasa de SupervivenciaRESUMEN
BACKGROUND: Haploidentical bone marrow transplant (haplo-BMT) offers near universal donor availability as a curative modality for individuals with severe sickle cell disease (SCD). However, the required intense immunodepletion is associated with increased infectious complications. A paucity of data exists on immune reconstitution following haplo-BMT for SCD. METHODS: A multi-institution learning collaborative was developed in the context of a phase II clinical trial of a non-myeloablative, related haplo-BMT with post-transplant cyclophosphamide for SCD. We report results from a cohort of 23 patients for whom immune reconstitution data up to one year were available. RESULTS: Median age was 14.8 years. Out of 23, 18 participants received pre-conditioning with azathioprine, hydroxyurea, and hypertransfusions. 70% (16/23) of participants had multiple indications for haplo-BMT. We observed excellent immune reconstitution of CD4, CD8, CD19, and CD56 cellular subsets by 6 months post transplant. Engraftment rate and event-free survival in this cohort were 100% and 96%, respectively. 70% (16/23) of patients had at least one viral reactivation or infection, including CMV 35% (8/23), HHV-6 22% (5/23), and polyoma virus 17% (4/23), with no cases of post-transplant lymphoproliferative disease. CONCLUSION: Further prospective studies are needed to better characterize immune reconstitution and the immunologic basis for increased viral reactivation following haplo-BMT with post-transplant cyclophosphamide for SCD.
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Anemia de Células Falciformes/complicaciones , Trasplante de Médula Ósea/efectos adversos , Ciclofosfamida/administración & dosificación , Reconstitución Inmune , Inmunosupresores/administración & dosificación , Activación Viral , Adolescente , Adulto , Niño , Ensayos Clínicos Fase II como Asunto , Supervivencia sin Enfermedad , Enfermedad Injerto contra Huésped , Humanos , Estudios Prospectivos , Acondicionamiento Pretrasplante/efectos adversos , Trasplante Haploidéntico/efectos adversos , Adulto JovenRESUMEN
Next generation sequencing of viral populations has advanced our understanding of viral population dynamics, the development of drug resistance, and escape from host immune responses. Many applications require complete gene sequences, which can be impossible to reconstruct from short reads. HIV env, the protein of interest for HIV vaccine studies, is exceptionally challenging for long-read sequencing and analysis due to its length, high substitution rate, and extensive indel variation. While long-read sequencing is attractive in this setting, the analysis of such data is not well handled by existing methods. To address this, we introduce FLEA (Full-Length Envelope Analyzer), which performs end-to-end analysis and visualization of long-read sequencing data. FLEA consists of both a pipeline (optionally run on a high-performance cluster), and a client-side web application that provides interactive results. The pipeline transforms FASTQ reads into high-quality consensus sequences (HQCSs) and uses them to build a codon-aware multiple sequence alignment. The resulting alignment is then used to infer phylogenies, selection pressure, and evolutionary dynamics. The web application provides publication-quality plots and interactive visualizations, including an annotated viral alignment browser, time series plots of evolutionary dynamics, visualizations of gene-wide selective pressures (such as dN/dS) across time and across protein structure, and a phylogenetic tree browser. We demonstrate how FLEA may be used to process Pacific Biosciences HIV env data and describe recent examples of its use. Simulations show how FLEA dramatically reduces the error rate of this sequencing platform, providing an accurate portrait of complex and variable HIV env populations. A public instance of FLEA is hosted at http://flea.datamonkey.org. The Python source code for the FLEA pipeline can be found at https://github.com/veg/flea-pipeline. The client-side application is available at https://github.com/veg/flea-web-app. A live demo of the P018 results can be found at http://flea.murrell.group/view/P018.
Asunto(s)
Alineación de Secuencia/métodos , Análisis de Secuencia de ADN/métodos , Virus/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Filogenia , Programas InformáticosRESUMEN
PURPOSE: We prospectively investigated contamination of high-contact surfaces in the operating room (OR) using adenosine triphosphate (ATP) monitoring. We tested whether contamination would increase from morning (AM) to afternoon (PM), despite cleaning between cases. Second, we compared the degree of OR contamination to non-OR control sites. METHODS: ORs with high case volumes were selected for the study. Ten sites in each OR were swabbed using the AccuPoint® HC ATP Sanitation Monitoring device, which provided a numerical measure of contamination (relative light units, RLUs). According to the manufacturer, surfaces are considered clean at ≤ 400 RLUs. AM measurements were taken before the start of surgical cases and PM measurements were taken after cases were completed. RESULTS: Eighty morning and 70 afternoon samples were obtained from 8 ORs. Apart from the OR floor, laryngoscope handles had the highest level of morning contamination (1204 RLUs, interquartile range 345, 2603), with 75% of AM samples and 100% of PM samples exceeding 400 RLUs. This contamination was comparable to hospital toilet seats (87% of samples exceeding 400 RLUs). No sites showed statistically significant increases in contamination from AM to PM. CONCLUSION: Apart from the OR floors, laryngoscope handles emerged as a key OR site where improved cleaning practices may reduce cross-contamination risk. While some sites showed increased contamination over the course of the day, none of these met statistical significance thereby offering tentative evidence that current cleaning practices during case turnover are effective for most sites.
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Adenosina Trifosfato/análisis , Mediciones Luminiscentes , Quirófanos , Humanos , Estudios ProspectivosRESUMEN
Mastocytosis is a group of heterogeneous disorders resulting from the clonal proliferation of abnormal mast cells and their accumulation in the skin and/or in various extracutaneous organs. Systemic mastocytosis is the most common form of mastocytosis diagnosed in adults, characterized by mast cell infiltration of one or more extracutaneous organs (with or without skin involvement). The identification of KIT D816V mutation and the emergence of novel targeted therapies have significantly improved the diagnosis and treatment of systemic mastocytosis. However, certain aspects of clinical care, particularly the diagnosis, assessment, and management of mediator-related symptoms continue to present challenges. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with systemic mastocytosis.
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Anafilaxia/terapia , Mastocitosis Sistémica/terapia , Oncología Médica/normas , Grupo de Atención al Paciente/normas , Anafilaxia/diagnóstico , Anafilaxia/inmunología , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/genética , Biopsia , Médula Ósea/efectos de los fármacos , Médula Ósea/patología , Trasplante de Células Madre Hematopoyéticas/métodos , Trasplante de Células Madre Hematopoyéticas/normas , Antagonistas de los Receptores Histamínicos/farmacología , Antagonistas de los Receptores Histamínicos/uso terapéutico , Humanos , Inmunofenotipificación/métodos , Inmunofenotipificación/normas , Mastocitos/efectos de los fármacos , Mastocitos/inmunología , Mastocitos/metabolismo , Mastocitosis Sistémica/diagnóstico , Mastocitosis Sistémica/genética , Mastocitosis Sistémica/inmunología , Oncología Médica/métodos , Terapia Molecular Dirigida/métodos , Terapia Molecular Dirigida/normas , Mutación , Proteínas de Fusión Oncogénica/genética , Proteínas Proto-Oncogénicas c-kit/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Sociedades Médicas/normas , Trasplante Homólogo/métodos , Trasplante Homólogo/normas , Resultado del Tratamiento , Factores de Escisión y Poliadenilación de ARNm/genéticaRESUMEN
Although single nucleotide polymorphisms (SNPs) in folate-mediated pathways predict susceptibility to choline deficiency during severe choline deprivation, it is unknown if effects persist at recommended intakes. Thus, we used stable isotope liquid chromatography-mass spectrometry (LC-MS) methodology to examine the impact of candidate SNPs on choline metabolism in a long-term, randomized, controlled feeding trial among pregnant, lactating, and nonpregnant (NP) women consuming 480 or 930 mg/d choline (22% as choline-d9, with d9 indicating a deuterated trimethyl amine group) and meeting folate-intake recommendations. Variants impairing folate metabolism, methylenetetrahydrofolate reductase (MTHFR) rs1801133, methionine synthase (MTR) rs1805087 [wild-type (WT)], MTR reductase (MTRR) rs1801394, and methylenetetrahydrofolate dehydrogenase-methenyltetrahydrofolate cyclohydrolase-formyltetrahydrofolate synthetase (MTHFD1) rs2236225, influenced choline dynamics, frequently through interactions with reproductive state and choline intake, with fewer genotypic alterations observed among pregnant women. Women with these variants partitioned more dietary choline toward phosphatidylcholine (PC) biosynthesis via the cytidine diphosphate (CDP)-choline pathway at the expense of betaine synthesis even when use of betaine as a methyl donor was increased. Choline intakes of 930 mg/d restored partitioning of dietary choline between betaine and CDP-PC among NP (MTHFR rs1801133 and MTR rs1805087 WT) and lactating (MTHFD1 rs2236225) women with risk genotypes. Overall, our findings indicate that loss-of-function variants in folate-metabolizing enzymes strain cellular PC production, possibly via impaired folate-dependent phosphatidylethanolamine-N-methyltransferase (PEMT)-PC synthesis, and suggest that women with these risk genotypes may benefit from choline intakes exceeding current recommendations.-Ganz, A. B., Shields, K., Fomin, V. G., Lopez, Y. S., Mohan, S., Lovesky, J., Chuang, J. C., Ganti, A., Carrier, B., Yan, J., Taeswuan, S., Cohen, V. V., Swersky, C. C., Stover, J. A., Vitiello, G. A., Malysheva, O. V., Mudrak, E., Caudill, M. A. Genetic impairments in folate enzymes increase dependence on dietary choline for phosphatidylcholine production at the expense of betaine synthesis.
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Betaína/metabolismo , Colina/genética , Dieta , Ácido Fólico/genética , Fosfatidilcolinas/genética , Polimorfismo de Nucleótido Simple/genética , Betaína/farmacología , Colina/metabolismo , Femenino , Deficiencia de Ácido Fólico/genética , Deficiencia de Ácido Fólico/metabolismo , Genotipo , Humanos , Lactancia/fisiología , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Fosfatidilcolinas/biosíntesisRESUMEN
Myeloproliferative neoplasms (MPNs) are a group of heterogeneous disorders of the hematopoietic system that include myelofibrosis (MF), polycythemia vera (PV), and essential thrombocythemia (ET). PV and ET are characterized by significant thrombohemorrhagic complications and a high risk of transformation to MF and acute myeloid leukemia. The diagnosis and management of PV and ET has evolved since the identification of mutations implicated in their pathogenesis. These NCCN Guideline Insights discuss the recommendations outlined in the NCCN Guidelines for the risk stratification, treatment, and special considerations for the management of PV and ET.