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1.
Nat Immunol ; 16(8): 810-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26147687

RESUMO

Foxm1 is known as a typical proliferation-associated transcription factor. Here we found that Foxm1 was essential for maintenance of the quiescence and self-renewal capacity of hematopoietic stem cells (HSCs) in vivo in mice. Reducing expression of FOXM1 also decreased the quiescence of human CD34(+) HSCs and progenitor cells, and its downregulation was associated with a subset of myelodysplastic syndrome (MDS). Mechanistically, Foxm1 directly bound to the promoter region of the gene encoding the receptor Nurr1 (Nr4a2; called 'Nurr1' here), inducing transcription, while forced expression of Nurr1 reversed the loss of quiescence observed in Foxm1-deficient cells in vivo. Thus, our studies reveal a previously unrecognized role for Foxm1 as a critical regulator of the quiescence and self-renewal of HSCs mediated at least in part by control of Nurr1 expression.


Assuntos
Proliferação de Células/genética , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Animais , Células Cultivadas , Citometria de Fluxo , Proteína Forkhead Box M1 , Fatores de Transcrição Forkhead/metabolismo , Perfilação da Expressão Gênica , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Regiões Promotoras Genéticas/genética , Ligação Proteica , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa
2.
Genet Epidemiol ; 48(3): 141-147, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38334222

RESUMO

Individual probabilistic assessments on the risk of cancer, primary or secondary, will not be understood by most patients. That is the essence of our arguments in this paper. Greater understanding can be achieved by extensive, intensive, and detailed counseling. But since probability itself is a concept that easily escapes our everyday intuition-consider the famous Monte Hall paradox-then it would also be wise to advise patients and potential patients, to not put undue weight on any probabilistic assessment. Such assessments can be of value to the epidemiologist in the investigation of different potential etiologies describing cancer evolution or to the clinical trialist as a way to maximize design efficiency. But to an ordinary individual we cannot anticipate that these assessments will be correctly interpreted.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Probabilidade , Medição de Risco
3.
Blood ; 139(14): 2212-2226, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35061876

RESUMO

Non-Hispanic Black (NHB) and Hispanic patients with acute myeloid leukemia (AML) have higher mortality rates than non-Hispanic White (NHW) patients despite more favorable genetics and younger age. A discrete survival analysis was performed on 822 adult patients with AML from 6 urban cancer centers and revealed inferior survival among NHB (hazard ratio [HR] = 1.59; 95% confidence interval [CI]: 1.15, 2.22) and Hispanic (HR = 1.25; 95% CI: 0.88, 1.79) patients compared with NHW patients. A multilevel analysis of disparities was then conducted to investigate the contribution of neighborhood measures of structural racism on racial/ethnic differences in survival. Census tract disadvantage and affluence scores were individually calculated. Mediation analysis of hazard of leukemia death between groups was examined across 6 composite variables: structural racism (census tract disadvantage, affluence, and segregation), tumor biology (European Leukemia Network risk and secondary leukemia), health care access (insurance and clinical trial enrollment), comorbidities, treatment patterns (induction intensity and transplant utilization), and intensive care unit (ICU) admission during induction chemotherapy. Strikingly, census tract measures accounted for nearly all of the NHB-NHW and Hispanic-NHW disparity in leukemia death. Treatment patterns, including induction intensity and allogeneic transplant, and treatment complications, as assessed by ICU admission during induction chemotherapy, were additional mediators of survival disparities in AML. This is the first study to formally test mediators for observed disparities in AML survival and highlights the need to investigate the mechanisms by which structural racism interacts with known prognostic and treatment factors to influence leukemia outcomes.


Assuntos
Leucemia Mieloide Aguda , Racismo Sistêmico , Adulto , Etnicidade , Disparidades nos Níveis de Saúde , Hispânico ou Latino , Humanos , Leucemia Mieloide Aguda/terapia , População Branca
4.
Am J Dermatopathol ; 46(7): 443-446, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38648045

RESUMO

ABSTRACT: Richter syndrome (RS) describes a phenomenon in which a patient with chronic lymphocytic leukemia (CLL) develops an aggressive lymphoma, most commonly diffuse large B-cell lymphoma (DLBCL). Reports of cutaneous RS remain exceedingly rare. We report a 61-year-old woman with relapsed/refractory CLL presenting with several subcutaneous nodules on her arms and legs and a single dermal plaque on her abdomen. Skin biopsy revealed a diagnosis of DLBCL, ABC-type, and her clinical status rapidly deteriorated following diagnosis. We review the variety of clinical presentations of cutaneous RS, its association with CLL, risk factors for RS development in CLL patients, and the distinctive histopathologic and immunophenotypic features of DLBCL. We hope to highlight the importance of prompt skin biopsy in patients with CLL presenting with progressive skin lesions and increase awareness of this aggressive clinical syndrome.


Assuntos
Leucemia Linfocítica Crônica de Células B , Linfoma Difuso de Grandes Células B , Neoplasias Cutâneas , Humanos , Feminino , Pessoa de Meia-Idade , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/patologia , Neoplasias Cutâneas/patologia , Evolução Fatal , Síndrome , Biópsia
5.
Ann Intern Med ; 176(4): 515-523, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36940444

RESUMO

BACKGROUND: Patients hospitalized with COVID-19 have an increased incidence of thromboembolism. The role of extended thromboprophylaxis after hospital discharge is unclear. OBJECTIVE: To determine whether anticoagulation is superior to placebo in reducing death and thromboembolic complications among patients discharged after COVID-19 hospitalization. DESIGN: Prospective, randomized, double-blind, placebo-controlled clinical trial. (ClinicalTrials.gov: NCT04650087). SETTING: Done during 2021 to 2022 among 127 U.S. hospitals. PARTICIPANTS: Adults aged 18 years or older hospitalized with COVID-19 for 48 hours or more and ready for discharge, excluding those with a requirement for, or contraindication to, anticoagulation. INTERVENTION: 2.5 mg of apixaban versus placebo twice daily for 30 days. MEASUREMENTS: The primary efficacy end point was a 30-day composite of death, arterial thromboembolism, and venous thromboembolism. The primary safety end points were 30-day major bleeding and clinically relevant nonmajor bleeding. RESULTS: Enrollment was terminated early, after 1217 participants were randomly assigned, because of a lower than anticipated event rate and a declining rate of COVID-19 hospitalizations. Median age was 54 years, 50.4% were women, 26.5% were Black, and 16.7% were Hispanic; 30.7% had a World Health Organization severity score of 5 or greater, and 11.0% had an International Medical Prevention Registry on Venous Thromboembolism risk prediction score of greater than 4. Incidence of the primary end point was 2.13% (95% CI, 1.14 to 3.62) in the apixaban group and 2.31% (CI, 1.27 to 3.84) in the placebo group. Major bleeding occurred in 2 (0.4%) and 1 (0.2%) and clinically relevant nonmajor bleeding occurred in 3 (0.6%) and 6 (1.1%) apixaban-treated and placebo-treated participants, respectively. By day 30, thirty-six (3.0%) participants were lost to follow-up, and 8.5% of apixaban and 11.9% of placebo participants permanently discontinued the study drug treatment. LIMITATIONS: The introduction of SARS-CoV-2 vaccines decreased the risk for hospitalization and death. Study enrollment spanned the peaks of the Delta and Omicron variants in the United States, which influenced illness severity. CONCLUSION: The incidence of death or thromboembolism was low in this cohort of patients discharged after hospitalization with COVID-19. Because of early enrollment termination, the results were imprecise and the study was inconclusive. PRIMARY FUNDING SOURCE: National Institutes of Health.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Hemorragia , Tromboembolia Venosa , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anticoagulantes/efeitos adversos , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Método Duplo-Cego , Hemorragia/induzido quimicamente , Hospitalização , Estudos Prospectivos , SARS-CoV-2 , Resultado do Tratamento , Tromboembolia Venosa/tratamento farmacológico
6.
Mol Genet Metab ; 140(3): 107670, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37542766

RESUMO

Acute hepatic porphyria (AHP) is a group of four rare inherited diseases, each resulting from a deficiency in a distinct enzyme in the heme biosynthetic pathway. Characterized by acute neurovisceral symptoms that may mimic other medical and psychiatric conditions, lack of recognition of the disease often leads to a delay in diagnosis and initiation of effective treatment. Biochemical testing for pathway intermediates that accumulate when the disease is active forms the basis for screening and establishing a diagnosis. Subsequent genetic analysis identifies the pathogenic variant, supporting screening of family members and genetic counseling. Management of AHP involves avoidance of known exogenous and hormonal triggers, symptomatic treatment, and prevention of recurrent attacks. Here we describe six case studies from our own real-world experience to highlight current recommendations and challenges associated with the diagnosis and long-term management of the disease.


Assuntos
Porfobilinogênio , Porfirias Hepáticas , Humanos , Porfirias Hepáticas/diagnóstico , Porfirias Hepáticas/genética , Porfirias Hepáticas/terapia , Sintase do Porfobilinogênio , Heme/genética
7.
J Am Acad Dermatol ; 89(6): 1227-1237, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36041558

RESUMO

Erythropoietic protoporphyria and X-linked protoporphyria are rare genetic photodermatoses. Limited expertise with these disorders among physicians leads to diagnostic delays. Here, we present evidence-based consensus guidelines for the diagnosis, monitoring, and management of erythropoietic protoporphyria and X-linked protoporphyria. A systematic literature review was conducted, and reviewed among subcommittees of experts, divided by topic. Consensus on guidelines was reached within each subcommittee and then among all members of the committee. The appropriate biochemical and genetic testing to establish the diagnosis is reviewed in addition to the interpretation of results. Prevention of symptoms, management of acute phototoxicity, and pharmacologic and nonpharmacologic treatment options are discussed. The importance of ongoing monitoring for liver disease, iron deficiency, and vitamin D deficiency is discussed with management guidance. Finally, management of pregnancy and surgery and the safety of other therapies are summarized. We emphasize that these are multisystemic disorders that require longitudinal monitoring. These guidelines provide a structure for evidence-based diagnosis and management for practicing physicians. Early diagnosis and management of these disorders are essential, particularly given the availability of new and emerging therapies.


Assuntos
Dermatite Fototóxica , Doenças Genéticas Ligadas ao Cromossomo X , Hepatopatias , Guias de Prática Clínica como Assunto , Protoporfiria Eritropoética , Humanos , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/terapia , Doenças Genéticas Ligadas ao Cromossomo X/genética , Protoporfiria Eritropoética/diagnóstico , Protoporfiria Eritropoética/genética , Protoporfiria Eritropoética/terapia
8.
Sensors (Basel) ; 23(10)2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37430842

RESUMO

This paper provides a novel methodology for human-driven decision support for capacity allocation in labour-intensive manufacturing systems. In such systems (where output depends solely on human labour) it is essential that any changes aimed at improving productivity are informed by the workers' actual working practices, rather than attempting to implement strategies based on an idealised representation of a theoretical production process. This paper reports how worker position data (obtained by localisation sensors) can be used as input to process mining algorithms to generate a data-driven process model to understand how manufacturing tasks are actually performed and how this model can then be used to build a discrete event simulation to investigate the performance of capacity allocation adjustments made to the original working practice observed in the data. The proposed methodology is demonstrated using a real-world dataset generated by a manual assembly line involving six workers performing six manufacturing tasks. It is found that, with small capacity adjustments, one can reduce the completion time by 7% (i.e., without requiring any additional workers), and with an additional worker a 16% reduction in completion time can be achieved by increasing the capacity of the bottleneck tasks which take relatively longer time than others.

9.
Crim Law Forum ; 34(1): 1-41, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36818492

RESUMO

A displaced population of Palestine Arabs, numbering over seven million, is dispersed around the world, with major concentrations in Lebanon, Jordan, Syria, and Palestine itself. This population is prohibited from entry for renewed residence in home areas situated in Israel. In international law a right of return to one's country is guaranteed as a matter of fundamental rights. Severe deprivation of internationally defined rights victimizing a civilian population based on ethnicity or nationality constitutes the crime of persecution, a sub-category of crimes against humanity, prosecutable at the International Criminal Court. With respect to a major portion of the displaced Palestine Arabs, jurisdictional prerequisites obtain for the opening of an investigation that might lead to charges against Israeli officials responsible for denying return to the Palestine Arabs.

10.
Stat Sin ; 32: 1983-2005, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36643072

RESUMO

We investigate a statistical framework for Phase I clinical trials that test the safety of two or more agents in combination. For such studies, the traditional assumption of a simple monotonic relation between dose and the probability of an adverse event no longer holds. Nonetheless, the dose toxicity (adverse event) relationship will obey an assumption of partial ordering in that there will be pairs of combinations for which the ordering of the toxicity probabilities is known. Some authors have considered how to best estimate the maximum tolerated dose (a dose providing a rate of toxicity as close as possible to some target rate) in this setting. A related, and equally interesting, problem is to partition the 2-dimensional dose space into two sub-regions: doses with probabilities of toxicity lower and greater than the target. We carry out a detailed investigation of this problem. The theoretical framework for this is the recently presented semiparametric dose finding method. This results in a number of proposals one of which can be viewed as an extension of the Product of Independent beta Priors Escalation method (PIPE). We derive useful asymptotic properties which also apply to the PIPE method when seen as a special case of the more general method given here. Simulation studies provide added confidence concerning the good behaviour of the operating characteristics.

11.
JAMA ; 327(3): 227-236, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35040887

RESUMO

Importance: Platelets represent a potential therapeutic target for improved clinical outcomes in patients with COVID-19. Objective: To evaluate the benefits and risks of adding a P2Y12 inhibitor to anticoagulant therapy among non-critically ill patients hospitalized for COVID-19. Design, Setting, and Participants: An open-label, bayesian, adaptive randomized clinical trial including 562 non-critically ill patients hospitalized for COVID-19 was conducted between February 2021 and June 2021 at 60 hospitals in Brazil, Italy, Spain, and the US. The date of final 90-day follow-up was September 15, 2021. Interventions: Patients were randomized to a therapeutic dose of heparin plus a P2Y12 inhibitor (n = 293) or a therapeutic dose of heparin only (usual care) (n = 269) in a 1:1 ratio for 14 days or until hospital discharge, whichever was sooner. Ticagrelor was the preferred P2Y12 inhibitor. Main Outcomes and Measures: The composite primary outcome was organ support-free days evaluated on an ordinal scale that combined in-hospital death (assigned a value of -1) and, for those who survived to hospital discharge, the number of days free of respiratory or cardiovascular organ support up to day 21 of the index hospitalization (range, -1 to 21 days; higher scores indicate less organ support and better outcomes). The primary safety outcome was major bleeding by 28 days as defined by the International Society on Thrombosis and Hemostasis. Results: Enrollment of non-critically ill patients was discontinued when the prespecified criterion for futility was met. All 562 patients who were randomized (mean age, 52.7 [SD, 13.5] years; 41.5% women) completed the trial and 87% received a therapeutic dose of heparin by the end of study day 1. In the P2Y12 inhibitor group, ticagrelor was used in 63% of patients and clopidogrel in 37%. The median number of organ support-free days was 21 days (IQR, 20-21 days) among patients in the P2Y12 inhibitor group and was 21 days (IQR, 21-21 days) in the usual care group (adjusted odds ratio, 0.83 [95% credible interval, 0.55-1.25]; posterior probability of futility [defined as an odds ratio <1.2], 96%). Major bleeding occurred in 6 patients (2.0%) in the P2Y12 inhibitor group and in 2 patients (0.7%) in the usual care group (adjusted odds ratio, 3.31 [95% CI, 0.64-17.2]; P = .15). Conclusions and Relevance: Among non-critically ill patients hospitalized for COVID-19, the use of a P2Y12 inhibitor in addition to a therapeutic dose of heparin, compared with a therapeutic dose of heparin only, did not result in an increased odds of improvement in organ support-free days within 21 days during hospitalization. Trial Registration: ClinicalTrials.gov Identifier: NCT04505774.


Assuntos
Anticoagulantes/administração & dosagem , Tratamento Farmacológico da COVID-19 , Heparina/administração & dosagem , Pacientes Internados , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/efeitos adversos , COVID-19/sangue , COVID-19/mortalidade , Clopidogrel/administração & dosagem , Clopidogrel/efeitos adversos , Comorbidade , Oxigenação por Membrana Extracorpórea/estatística & dados numéricos , Feminino , Hemorragia/induzido quimicamente , Heparina/efeitos adversos , Mortalidade Hospitalar , Humanos , Masculino , Futilidade Médica , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Oxigenoterapia/estatística & dados numéricos , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/efeitos adversos , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos , Receptores Purinérgicos P2Y12 , Respiração Artificial/estatística & dados numéricos , Trombose/epidemiologia , Ticagrelor/administração & dosagem , Ticagrelor/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
12.
Br J Cancer ; 125(7): 920-926, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34112947

RESUMO

The aims of Phase 1 trials in oncology have broadened considerably from simply demonstrating that the agent/regimen of interest is well tolerated in a relatively heterogeneous patient population to addressing multiple objectives under the heading of early-phase trials and, if possible, obtaining reliable evidence regarding clinical activity to lead to drug approvals via the Accelerated Approval approach or Breakthrough Therapy designation in cases where the tumours are rare, prognosis is poor or where there might be an unmet therapeutic need. Constructing a Phase 1 design that can address multiple objectives within the context of a single trial is not simple. Randomisation can play an important role, but carrying out such randomisation according to the principles of equipoise is a significant challenge in the Phase 1 setting. If the emerging data are not sufficient to definitively address the aims early on, then a proper design can reduce biases, enhance interpretability, and maximise information so that the Phase 1 data can be more compelling. This article outlines objectives and design considerations that need to be adhered to in order to respect ethical and scientific principles required for research in human subjects in early phase clinical trials.


Assuntos
Ensaios Clínicos Fase I como Assunto/métodos , Neoplasias/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Viés , Aprovação de Drogas , Humanos , Neoplasias/metabolismo , Prognóstico , Resultado do Tratamento
13.
Stat Med ; 40(2): 240-253, 2021 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-33053601

RESUMO

Little has been published in terms of dose-finding methodology in virology. Aside from a few papers focusing on HIV, the considerable progress in dose-finding methodology of the last 25 years has focused almost entirely on oncology. While adverse reactions to cytotoxic drugs may be life threatening, for anti-viral agents we anticipate something different: side effects that provoke the cessation of treatment. This would correspond to treatment failure. On the other hand, success would not be yes/no but would correspond to a range of responses, from small, no more than say 20% reduction in viral load to the complete elimination of the virus. Less than total success matters since this may allow the patient to achieve immune-mediated clearance. The motivation for this article is an upcoming dose-finding trial in chronic norovirus infection. We propose a novel methodology whose goal is twofold: first, to identify the dose that provides the most favorable distribution of treatment outcomes, and, second, to do this in a way that maximizes the treatment benefit for the patients included in the study.


Assuntos
Antivirais/administração & dosagem , Ensaios Clínicos como Assunto/estatística & dados numéricos , Viroses/tratamento farmacológico , Relação Dose-Resposta a Droga , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Dose Máxima Tolerável , Projetos de Pesquisa
15.
Am J Hematol ; 95(8): 937-943, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32311140

RESUMO

Relapsed or refractory acute myeloid leukemia (R/R AML) has a poor prognosis and is best treated with salvage chemotherapy as a bridge to allogeneic stem cell transplant (alloSCT). However, the optimal salvage therapy remains unknown. Here we compared two salvage regimens; mitoxantrone, etoposide, and cytarabine (MEC) and mitoxantrone and high-dose Ara-C (Ara-C couplets). We analyzed 155 patients treated at three academic institutions between 1998 and 2017; 87 patients received MEC and 68 received Ara-C couplets. The primary endpoint was overall response (OR). Secondary endpoints included progression-free survival (PFS), overall survival (OS), duration of hospitalization, hematologic and nonhematologic toxicities, and success in proceeding to alloSCT. Baseline characteristics of the cohorts were well matched, though patients receiving Ara-C couplets had more co-morbidities (48.5% vs 33%; P = .07). OR was achieved in 43.7% of MEC and 54.4% of Ara-C couplets patients (P = .10). Ara-C couplets patients also trended towards a longer OS and PFS, more frequently proceeded to alloSCT (31% vs 54.4%; P = .003), and experienced less febrile neutropenia (94% vs 72%; P < .001) and grade 3/4 gastrointestinal toxicities (17.2% vs 2.94%; P = .005). No significant differences in other toxicities or median duration of hospitalization were noted. This is the first multi-institutional study directly comparing these regimens in a racially diverse population of R/R AML patients. Although these regimens have equivalent efficacy in terms of achieving OR, Ara-C couplets use is associated with significant reductions in toxicities, suggesting it should be used more frequently in these patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Citarabina/intoxicação , Citarabina/uso terapêutico , Etoposídeo/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Mitoxantrona/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Citarabina/farmacologia , Etoposídeo/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitoxantrona/farmacologia , Recidiva , Adulto Jovem
16.
Curr Neurol Neurosci Rep ; 20(12): 56, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-33026560

RESUMO

PURPOSE OF REVIEW: To review the peripheral neurological complications of the acute hepatic porphyrias, as well as the latest advances in their pathophysiology and management. RECENT FINDINGS: The diagnosis of porphyric neuropathy remains challenging as varying neuropathic patterns are encountered depending on disease stage, including a non-length-dependent distribution pattern. The major pathophysiologic mechanism is δ-aminolevulinic acid (ALA)-induced neurotoxicity. The less restrictive blood-nerve barrier in the autonomic ganglia and myenteric plexus may explain the frequency of dysautonomic manifestations. Recently, a prophylactic small interfering RNA (siRNA)-based therapy that reduces hepatic ALA Synthase-1 mRNA was approved for patients with recurrent neuro-visceral attacks. Neurologists should appreciate the varying patterns of porphyric neuropathy. As with most toxin-induced axonopathies, long-term outcomes depend on early diagnosis and treatment. While the short-term clinical and biochemical benefits of siRNA-based therapy are known, its long-term effects on motor recovery, chronic pain, and dysautonomic manifestations are yet to be determined.


Assuntos
Doenças do Sistema Nervoso Periférico , Polineuropatias , Porfirias Hepáticas , Humanos , Doenças do Sistema Nervoso Periférico/diagnóstico , Doenças do Sistema Nervoso Periférico/terapia , Sintase do Porfobilinogênio
17.
Pharm Stat ; 19(2): 137-144, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31692233

RESUMO

This paper studies the notion of coherence in interval-based dose-finding methods. An incoherent decision is either (a) a recommendation to escalate the dose following an observed dose-limiting toxicity or (b) a recommendation to deescalate the dose following a non-dose-limiting toxicity. In a simulated example, we illustrate that the Bayesian optimal interval method and the Keyboard method are not coherent. We generated dose-limiting toxicity outcomes under an assumed set of true probabilities for a trial of n=36 patients in cohorts of size 1, and we counted the number of incoherent dosing decisions that were made throughout this simulated trial. Each of the methods studied resulted in 13/36 (36%) incoherent decisions in the simulated trial. Additionally, for two different target dose-limiting toxicity rates, 20% and 30%, and a sample size of n=30 patients, we randomly generated 100 dose-toxicity curves and tabulated the number of incoherent decisions made by each method in 1000 simulated trials under each curve. For each method studied, the probability of incurring at least one incoherent decision during the conduct of a single trial is greater than 75%. Coherency is an important principle in the conduct of dose-finding trials. Interval-based methods violate this principle for cohorts of size 1 and require additional modifications to overcome this shortcoming. Researchers need to take a closer look at the dose assignment behavior of interval-based methods when using them to plan dose-finding studies.


Assuntos
Ensaios Clínicos como Assunto/métodos , Simulação por Computador , Dose Máxima Tolerável , Teorema de Bayes , Ensaios Clínicos como Assunto/estatística & dados numéricos , Simulação por Computador/estatística & dados numéricos , Relação Dose-Resposta a Droga , Humanos
18.
Cancer ; 125(7): 1143-1154, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30548485

RESUMO

BACKGROUND: Granulocyte colony-stimulating factors (G-CSFs), which are used for the prevention of complications from chemotherapy-related neutropenia, are linked to the risk of developing second primary myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). The objective of this study was to examine the correlation between using a specific G-CSF agent and the risk of MDS/AML among older patients with non-Hodgkin lymphoma (NHL). METHODS: This was a retrospective cohort study of adults aged >65 years who were diagnosed with first primary NHL between 2001 and 2011. With data from the Surveillance, Epidemiology, and End Results-Medicare-linked database, adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for the risk of MDS/AML associated with the receipt of G-CSF(filgrastim and pegfilgrastim) in Cox proportional-hazards models, which were stratified according to treatment accounting for confounding by indication. RESULTS: Among 18,245 patients with NHL patients who had a median follow-up of 3.5 years, 56% received chemotherapy and/or immunotherapy, and G-CSF was most commonly used in those who received rituximab plus multiple chemotherapy regimens (77%). Subsequent MDS/AML diagnoses were identified in 666 patients (3.7%). A modest increased risk of MDS/AML was observed with the receipt of G-CSF (HR, 1.28; 95% CI, 1.01-1.62) and a trend was observed with increasing doses (Ptrend < .01). When specific agents were analyzed, an increased risk of MDS/AML was consistently observed with filgrastim (≥10 doses: HR, 1.67; 95% CI, 1.25-2.23), but not with pegfilgrastim (≥10 + doses: HR, 1.11; 95% CI, 0.84-1.45). CONCLUSIONS: A higher of MDS/AML was observed in patients with NHL risk among those who received G-CSF that was specific to the use of filgrastim (≥10 doses), but not pegfilgrastim. Neutropenia prophylaxis is an essential component of highly effective NHL treatment regimens. The differential risk related to the types of G-CSF agents used warrants further study given their increasing use and newly available, US Food and Drug Administration-approved, biosimilar products.


Assuntos
Filgrastim/uso terapêutico , Fármacos Hematológicos/uso terapêutico , Leucemia Mieloide Aguda/epidemiologia , Linfoma não Hodgkin/tratamento farmacológico , Síndromes Mielodisplásicas/epidemiologia , Segunda Neoplasia Primária/epidemiologia , Neutropenia/prevenção & controle , Polietilenoglicóis/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Feminino , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Armazenamento e Recuperação da Informação , Masculino , Medicare , Neutropenia/induzido quimicamente , Rituximab/efeitos adversos , Programa de SEER , Estados Unidos/epidemiologia
19.
J Oncol Pharm Pract ; 25(1): 226-228, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28857712

RESUMO

Busulfan is an alkylating agent used in pre-transplant conditioning for patients undergoing hematopoietic stem cell transplantation. Several factors contribute to variations in busulfan drug disposition including bioavailability, age, liver function, genetic polymorphisms, and concurrent administration of other drugs. Busulfan is metabolized by hepatic oxidation via the cytochrome P450 3A4 system as well as through conjugation with glutathione. Interactions with drugs such as phenytoin, itraconazole, and metronidazole have been reported to alter busulfan clearance and result in sub- or supra-therapeutic concentrations. We report a case of a clinically significant drug interaction between intravenous busulfan and the bifunctional T-cell engager, blinatumomab, observed through busulfan therapeutic drug monitoring. We found that busulfan clearance was reduced resulting in a higher area under the concentration-time curve when it was administered 48 h after blinatumomab. Repeat busulfan pharmacokinetic testing two weeks later demonstrated increased clearance of the drug and a 31% higher dose recommendation. Similar to other protein therapeutics, cytokine elevations during blinatumomab treatment can lead to cytochrome 3A4 suppression. We hypothesize that the increased busulfan levels observed could be related to a cytokine-mediated CYP3A4 suppression. This represents a unique pharmacologic consideration in hematopoietic stem cell transplantation which would impact several drugs that undergo CYP3A4 metabolism, including calcineurin inhibitors, cyclophosphamide, sirolimus, and triazole antifungals. Additionally, this mechanism of CYP3A4 suppression may be relevant in treatments and disease states where cytokine levels are elevated such as haploidentical stem cell transplantation, graft-versus-host disease, and use of chimeric antigen receptor T-cell therapy.


Assuntos
Anticorpos Biespecíficos/metabolismo , Antineoplásicos/metabolismo , Bussulfano/metabolismo , Monitoramento de Medicamentos/métodos , Adulto , Anticorpos Biespecíficos/uso terapêutico , Antineoplásicos Alquilantes/metabolismo , Bussulfano/uso terapêutico , Interações Medicamentosas/fisiologia , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/metabolismo , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Masculino , Condicionamento Pré-Transplante/métodos
20.
Biol Blood Marrow Transplant ; 24(8): 1759-1765, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29656137

RESUMO

We report on the screening and development of haploidentical hematopoietic stem cell transplantation (HSCT) for adult patients with clinically aggressive sickle cell disease (SCD) at our institution. Of 50 adult SCD patients referred for HSCT between January 2014 and March 2017, 20% were denied by insurance. Of 41 patients initially screened, 10% lacked an available haploidentical donor, 29% had elevated donor-specific antibodies (DSAs), and 34% declined to proceed to HSCT. All 10 patients who were transplanted received peripheral blood stem cells. The initial 2 were conditioned with alemtuzumab/total body irradiation (TBI) 3 Gy followed by post-transplant cyclophosphamide and failed to engraft. The next 8 patients received the regimen developed at Johns Hopkins University with TBI 3 Gy. Granulocyte colony-stimulating factor was administered from day +12 in those with HbS < 30%. All 8 patients engrafted with a median time to neutrophil >.5 × 109/L of 22 days (range, 18 to 23). One patient subsequently lost the graft, and 7 (87.5%) maintained >95% donor cell chimerism at 1-year post-HSCT. Two patients developed acute graft-versus-host disease (GVHD) of at least grade II. One had chronic GVHD and died >1 year after HSCT of unknown causes. With a median follow-up of 16 months (range, 11 to 29), 7 patients (87.5%) are alive. Our findings suggest that limited insurance coverage, high rate of DSAs, and patient declining HSCT may limit the availability of haploidentical HSCT in adult SCD patients. The modified Hopkins regimen used here demonstrates high engraftment and low morbidity rates and should be tested in larger, multicenter, prospective clinical trials.


Assuntos
Anemia Falciforme/terapia , Sobrevivência de Enxerto , Transplante de Células-Tronco de Sangue Periférico/métodos , Transplante Haploidêntico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Condicionamento Pré-Transplante/métodos
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