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1.
Neurobiol Dis ; 184: 106218, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37394036

RESUMO

In patients with amyotrophic lateral sclerosis (ALS), disease symptoms and pathology typically spread in a predictable spatiotemporal pattern beginning at a focal site of onset and progressing along defined neuroanatomical tracts. Like other neurodegenerative diseases, ALS is characterized by the presence of protein aggregates in postmortem patient tissue. Cytoplasmic, ubiquitin-positive aggregates of TDP-43 are observed in approximately 97% of sporadic and familial ALS patients, while SOD1 inclusions are likely specific to cases of SOD1-ALS. Additionally, the most common subtype of familial ALS, caused by a hexanucleotide repeat expansion in the first intron of the C9orf72 gene (C9-ALS), is further characterized by the presence of aggregated dipeptide repeat proteins (DPRs). As we will describe, cell-to-cell propagation of these pathological proteins tightly correlates with the contiguous spread of disease. While TDP-43 and SOD1 are capable of seeding protein misfolding and aggregation in a prion-like manner, C9orf72 DPRs appear to induce (and transmit) a 'disease state' more generally. Multiple mechanisms of intercellular transport have been described for all of these proteins, including anterograde and retrograde axonal transport, extracellular vesicle secretion, and macropinocytosis. In addition to neuron-to-neuron transmission, transmission of pathological proteins occurs between neurons and glia. Given that the spread of ALS disease pathology corresponds with the spread of symptoms in patients, the various mechanisms by which ALS-associated protein aggregates propagate through the central nervous system should be closely examined.


Assuntos
Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/metabolismo , Superóxido Dismutase-1/metabolismo , Agregados Proteicos , Proteína C9orf72/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo
2.
Br J Dermatol ; 186(1): 153-166, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34427917

RESUMO

BACKGROUND: Mogamulizumab is a humanized antibody against chemokine receptor type 4. It was recently approved by the US Food and Drug Administration for relapsed or refractory mycosis fungoides (MF) and Sézary syndrome (SS). The most commonly reported adverse event in the phase III licensing trial was drug eruption (28%), now termed mogamulizumab-associated rash (MAR). Clinical recommendations about MAR and its treatment differ between the current package insert and postapproval insights reported from two single-centre studies that focused on its characterization, but less so on outcomes and clinicopathological differentiation from cutaneous T-cell lymphoma (CTCL). OBJECTIVES: To describe our experience in the diagnosis of MAR and treatment of patients with CTCL with mogamulizumab. METHODS: This is a single-centre retrospective case series study. RESULTS: We found a higher incidence of MAR in patients with CTCL (17 of 24, 68%) than previously reported. MAR development is associated with complete (11 of 17) or partial (four of 17) responses, with an overall response rate of 88%, compared with 29% (two of seven) in patients without MAR. Diagnosis of MAR may be obscured by its ability to mimic key CTCL features both clinically and histologically, but an absence of T-cell-receptor clonality and relatively decreased CD4 : CD8 ratio compared with baseline lesions strongly favour MAR over recurrent disease. CONCLUSIONS: MAR has the potential to create a significant management problem for patients on mogamulizumab. Misidentification of MAR as recurrent CTCL may detrimentally result in the premature discontinuation of mogamulizumab in patients whose disease is historically hard to treat. Thorough clinicopathological investigation of new lesions during treatment with mogamulizumab is required to inform ideal treatment decisions and achieve better outcomes.


Assuntos
Antineoplásicos , Exantema , Linfoma Cutâneo de Células T , Neoplasias Cutâneas , Anticorpos Monoclonais Humanizados , Antineoplásicos/efeitos adversos , Exantema/induzido quimicamente , Humanos , Linfoma Cutâneo de Células T/patologia , Estudos Retrospectivos , Neoplasias Cutâneas/patologia
3.
Acta Neurol Scand ; 135(2): 148-160, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27364959

RESUMO

Oseltamivir is contraindicated for people aged 10-19 in principle in Japan, due to concern about abnormal behaviours. Sudden death is another concern. This review examines growing evidence of their association and discusses underlying mechanisms of these sudden-onset type reactions to oseltamivir. First, the importance of animal models and the concept of human equivalent dose (HED) is summarized. Second, the specific condition for oseltamivir use, influenza infection, is reviewed. Third, findings from toxicity studies conducted prior to and after the marketing of oseltamivir are reported on to provide context on the observation of a possible causal association. Fourth, similarity and consistency of toxicity in humans with that in other animals is described. Finally, coherence of toxicokinetic and molecular level of evidence (channels, receptors and enzymes), including differences from the toxicity of other neuraminidase inhibitors, is reviewed. It is concluded that unchanged oseltamivir has various effects on the central nervous system (CNS) that may be related to clinical findings including hypothermia, abnormal behaviours including with fatal outcome, and sudden death. Among receptors and enzymes related to CNS action, it is known that oseltamivir inhibits nicotinic acetylcholine receptors, which are closely related to hypothermia, as well as human monoamine oxidase-A (MAO-A), which is closely related to abnormal or excitatory behaviours. Receptors such as GABAA , GABAB and NMDA and their related receptors/channels including Na+ and Ca2+ channels are thought to be other candidates for investigation related to respiratory suppression followed by sudden death and psychotic reactions (both acute and chronic), respectively.


Assuntos
Antivirais/efeitos adversos , Sistema Nervoso Central/efeitos dos fármacos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Oseltamivir/efeitos adversos , Receptores Nicotínicos , Animais , Antivirais/metabolismo , Sistema Nervoso Central/metabolismo , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/metabolismo , Inibidores Enzimáticos/efeitos adversos , Inibidores Enzimáticos/metabolismo , Humanos , Influenza Humana/tratamento farmacológico , Influenza Humana/metabolismo , Oseltamivir/metabolismo , Receptores Nicotínicos/metabolismo , Insuficiência Respiratória/induzido quimicamente , Insuficiência Respiratória/diagnóstico , Insuficiência Respiratória/metabolismo
4.
Ann Hematol ; 95(1): 27-33, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26382277

RESUMO

In 2008, the CDC published guidelines recommending screening of all persons undergoing treatment with rituximab to identify persons at risk of hepatitis B virus (HBV) reactivation. We evaluated implementation of this recommendation in veterans, who are at increased risk of HBV, and determined characteristics of those screened. We also evaluated a control setting, rates of hepatitis C virus (HCV) screening among the same rituximab-treated patients. There are no guidelines that recommend HCV screening prior to initiation of rituximab. Medical records of patients receiving rituximab between January 2006 and December 2012 were reviewed according to two time periods: 2006-2008 (period 1, pre-guidelines) and 2009-2012 (period 2, post-guidelines). Patient demographics, concomitant chemotherapy regimen (protocol, dose, duration), treatment indication, risk factors for hepatitis infection (substance abuse, homelessness, human immunodeficiency virus (HIV)), and HBV/HCV screening status were documented. During the study period, 102 patients were treated with rituximab (49 in period 1 and 53 in period 2). During periods 1 and 2, 22 and 32 % of rituximab-treated patients were screened for HBV, respectively (p = 0.375). Treatment during 2009 was the only significant predictor of HBV screening in the adjusted model (p = 0.01). For HCV during periods 1 and 2, 22 and 21 % of patients were screened, respectively (p = 1.00). There were no significant predictors of HCV screening. Rates of screening for HBV among rituximab-treated patients were low, both before and after dissemination of guidelines recommending universal HBV screening of rituximab-treated patients.


Assuntos
Antineoplásicos/uso terapêutico , Hepatite B/diagnóstico , Hepatite B/tratamento farmacológico , Programas de Rastreamento , Rituximab/uso terapêutico , Idoso , Antineoplásicos/farmacologia , Feminino , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Rituximab/farmacologia , Ativação Viral/efeitos dos fármacos , Ativação Viral/fisiologia
5.
Ann Oncol ; 26(7): 1390-5, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25926039

RESUMO

BACKGROUND: Although commonly used, early initiation of salvage androgen deprivation therapy (ADT) has not been proven to enhance survival. We evaluated whether prostate-specific antigen (PSA) anxiety or health literacy are associated with use of early salvage ADT among men with recurrent prostate cancer after radiotherapy. PATIENTS AND METHODS: The prospective Comprehensive, Observational, Multicenter, Prostate Adenocarcinoma Registry was used to study 375 men with biochemically recurrent prostate cancer after external beam radiation or brachytherapy. Multivariable logistic regression was used to determine whether PSA anxiety and health literacy are associated with salvage ADT as initial management after biochemical recurrence. RESULTS: Sixty-eight men (18.1%) received salvage ADT as initial management for PSA recurrence. Men with high PSA anxiety were twice as likely to receive salvage ADT compared with men who did not have high PSA anxiety on both univariable [28.8% versus 13.1%; odds ratio (OR) 2.15; 95% confidence interval (CI) 1.16-4.00; P = 0.015] and multivariable analysis [adjusted OR (AOR) 2.36; 95% CI 1.21-4.62; P = 0.012]. Furthermore, men who had higher levels of health literacy were nearly half as likely to undergo salvage ADT compared with men who had lower levels of health literacy on univariable analysis (15.2% versus 26.3%; OR 0.50; 95% CI 0.29-0.88; P = 0.016), with a trend toward this association on multivariable analysis (AOR 0.58; 95% CI 0.32-1.05; P = 0.07). CONCLUSIONS: Among men with PSA recurrence after radiotherapy, odds of use of salvage ADT were nearly twice as great among men with high PSA anxiety or low health literacy, suggesting that these men are receiving higher rates of unproven treatment. Given that early salvage ADT is costly, worsens quality of life, and has not been shown to improve survival, quality improvement strategies are needed for these individuals.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Transtornos de Ansiedade/tratamento farmacológico , Letramento em Saúde , Recidiva Local de Neoplasia/tratamento farmacológico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/tratamento farmacológico , Terapia de Salvação , Adenocarcinoma/sangue , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/psicologia , Adenocarcinoma/radioterapia , Idoso , Idoso de 80 Anos ou mais , Transtornos de Ansiedade/sangue , Transtornos de Ansiedade/etiologia , Braquiterapia/efeitos adversos , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/etiologia , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Neoplasias da Próstata/sangue , Neoplasias da Próstata/psicologia , Neoplasias da Próstata/radioterapia , Qualidade de Vida
6.
Nat Genet ; 27(1): 20-1, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11137993

RESUMO

IPEX is a fatal disorder characterized by immune dysregulation, polyendocrinopathy, enteropathy and X-linked inheritance (MIM 304930). We present genetic evidence that different mutations of the human gene FOXP3, the ortholog of the gene mutated in scurfy mice (Foxp3), causes IPEX syndrome. Recent linkage analysis studies mapped the gene mutated in IPEX to an interval of 17-20-cM at Xp11. 23-Xq13.3.


Assuntos
Proteínas de Ligação a DNA/genética , Ligação Genética/genética , Mutação/genética , Poliendocrinopatias Autoimunes/genética , Enteropatias Perdedoras de Proteínas/genética , Cromossomo X/genética , Sequência de Aminoácidos , Animais , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Feminino , Fatores de Transcrição Forkhead , Humanos , Masculino , Camundongos , Dados de Sequência Molecular , Linhagem , Fenótipo , Alinhamento de Sequência , Síndrome
7.
Neurobiol Aging ; 126: 44-57, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36931113

RESUMO

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with an average age-of-onset of ∼60 years and is usually fatal within 2-5 years of diagnosis. Mouse models based upon single gene mutations do not recapitulate all ALS pathological features. Environmental insults may also contribute to ALS, and ß-N-methylamino-L-alanine (BMAA) is an environmental toxin linked with an increased risk of developing ALS. BMAA, along with cycasin, are hypothesized to be the cause of the Guam-ALS epicenter of the 1950s. We developed a multihit model based on low expression of a dominant familial ALS TDP-43 mutation (Q331K) and chronic low-dose BMAA exposure. Our two-hit mouse model displayed a motor phenotype absent from either lesion alone. By LC/MS analysis, free BMAA was confirmed at trace levels in brain, and were as high as 405 ng/mL (free) and 208 ng/mL (protein-bound) in liver. Elevated BMAA levels in liver were associated with dysregulation of the unfolded protein response (UPR) pathway. Our data represent initial steps towards an ALS mouse model resulting from combined genetic and environmental insult.


Assuntos
Diamino Aminoácidos , Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Animais , Camundongos , Esclerose Lateral Amiotrófica/induzido quimicamente , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Doenças Neurodegenerativas/complicações , Neurônios Motores/patologia , Fenótipo , Diamino Aminoácidos/toxicidade , Diamino Aminoácidos/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças
8.
Astrophys J ; 889(2)2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32255818

RESUMO

We explore the fundamental limits to which reionization histories can be constrained using only large-scale cosmic microwave background (CMB) anisotropy measurements. The redshift distribution of the fractional ionization x e (z) affects the angular distribution of CMB polarization. We project constraints on the reionization history of the universe using low-noise full-sky temperature and E-mode measurements of the CMB. We show that the measured TE power spectrum, C ^ ℓ TE , has roughly one quarter of the constraining power of C ^ ℓ EE on the reionization optical depth τ, and its addition improves the precision on τ by 20% over using C ^ ℓ EE only. We also use a two-step reionization model with an additional high-redshift step, parameterized by an early ionization fraction x e min , and a late reionization step at z re. We find that future high signal-to-noise measurements of the multipoles 10 ⩽ ℓ < 20 are especially important for breaking the degeneracy between x e min and z re. In addition, we show that the uncertainties on these parameters determined from a map with sensitivity 10 µK arcmin are less than 5% larger than the uncertainties in the noiseless case, making this noise level a natural target for future large sky area E-mode measurements.

10.
Science ; 201(4353): 345-7, 1978 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-17793730

RESUMO

The recently developed direct counting technique for radiocarbon atoms has been used to measure the relative numbers of such atoms in various geological samples which had earlier been dated by the beta-ray counting method. Sample weights ranged from 3.5 to 15 milligrams. The dates determined by the two methods are consistent with each other. Further experience with the new method is also reported.

11.
Science ; 223(4631): 46-9, 1984 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-17752987

RESUMO

A new gravitational lens system, the triple radio source MG2016+112, has been discovered. Five emission lines at a redshift of 3.2733+/-0.0014 have been identified in the spectra of two stellar objects of magnitude 22.5 coincident with radio components 3.4 arc seconds apart. The lines are the narrowest ever observed in objects at such a large redshift. The redshift of a 23rd-magnitude extended optical object coincident with the third radio component has not been determined spectroscopically, but its known optical properties are consistent with those of a giant elliptical galaxy with a redshift of about 0.8.

12.
Science ; 198(4316): 508-10, 1977 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-17842139

RESUMO

Mass spectrometric methods have long been suggested as ways of measuring (14)C/(12)C ratios for carbon dating. One problem has been to distinguish between (14)N and (14)C. With negative ions and a tandem electrostatic accelerator, the (14)N background is virtually absent and fewer than three (14)C atoms in 10(16) atoms of (12)C have been easily measured.

13.
Rev Sci Instrum ; 90(9): 095104, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31575233

RESUMO

The Primordial Inflation Polarization Explorer (PIPER) is a balloon-borne telescope mission to search for inflationary gravitational waves from the early universe. PIPER employs two 32 × 40 arrays of superconducting transition-edge sensors, which operate at 100 mK. An open bucket Dewar of liquid helium maintains the receiver and telescope optics at 1.7 K. We describe the thermal design of the receiver and sub-Kelvin cooling with a continuous adiabatic demagnetization refrigerator (CADR). The CADR operates between 70 and 130 mK and provides ≈10 µW cooling power at 100 mK, nearly five times the loading of the two detector assemblies. We describe electronics and software to robustly control the CADR, overall CADR performance in flightlike integrated receiver testing, and practical considerations for implementation in the balloon float environment.

14.
Bone Marrow Transplant ; 40(3): 185-92, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17563736

RESUMO

Granulocyte-colony stimulating factor (G-CSF) is widely administered to donors who provide peripheral blood stem cells (PBSC) for individuals who undergo hematopoietic stem cell transplants. Questions have been raised about the safety of G-CSF in this setting. Herein, the Research on Adverse Drug Events and Reports (RADAR) project investigators reviewed the literature on G-CSF-associated adverse events in healthy individuals or persons with chronic neutropenia or cancer. Toxicities identified included bone pain and rare instances of splenic rupture, allergic reactions, flares of underlying autoimmune disorders, lung injury and vascular events. Among healthy individuals, four patients developed splenic rupture shortly after G-CSF administration and three patients developed acute myeloid leukemia 1 to 5 years after G-CSF administration. Registry studies identified no increased risks of malignancy among healthy individuals who received G-CSF before PBSC harvesting. However, more than 2000 donors would have to be followed for 10 years to detect a 10-fold increase in leukemia risk. Our review identifies bone pain as the most common toxicity of G-CSF administration. There are questions about a causal relationship between G-CSF administration and acute leukemia, but more long-term safety data from database registries are needed to adequately evaluate such a relationship.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Fator Estimulador de Colônias de Granulócitos/efeitos adversos , Mobilização de Células-Tronco Hematopoéticas/efeitos adversos , Neoplasias/complicações , Neutropenia/complicações , Osso e Ossos , Doença Crônica , Bases de Dados Factuais , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Transplante de Células-Tronco Hematopoéticas , Humanos , Hipersensibilidade/etiologia , Leucemia Mieloide Aguda/induzido quimicamente , Pneumopatias/induzido quimicamente , Lesão Pulmonar , Neoplasias/tratamento farmacológico , Neutropenia/tratamento farmacológico , Dor/induzido quimicamente , Sistema de Registros , Fatores de Risco , Ruptura Esplênica/induzido quimicamente , Fatores de Tempo , Transplante Homólogo , Doenças Vasculares/induzido quimicamente
15.
Bone Marrow Transplant ; 39(7): 425-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17310132

RESUMO

Zygomycosis is increasingly reported as a cause of life-threatening fungal infections. A higher proportion of cases reported over the last decades have been in cancer patients, with or without hematopoietic stem cell transplantation (HSCT). The new anti-fungal agent voriconazole is a recently identified risk factor for developing zygomycosis. We reviewed the clinical characteristics and outcomes of a large cohort of cancer patients who developed zygomycosis after exposure to voriconazole. Health care professionals at 13 large cancer centers provided clinical information on cancer patients with zygomycosis and prior exposure to voriconazole. Criteria for inclusion were 5 days or more of voriconazole use and diagnostic confirmation with tissue or histology. Fifty-eight cases were identified among patients with hematologic malignancies, 62% including patients who underwent a HSCT procedure. Fifty-six patients received voriconazole for primary or secondary prophylaxis against fungal infection. In addition to prior exposure to voriconazole, patients also had several of the previously established risk factors for zygomycosis. Amphotericin B was the most commonly prescribed anti-fungal therapy. Overall mortality was 73%. We conclude that zygomycosis after exposure to voriconazole is a recently described entity that is frequently fatal, despite treatment with currently available anti-fungal agents and surgery.


Assuntos
Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Pirimidinas/administração & dosagem , Triazóis/administração & dosagem , Zigomicose/epidemiologia , Zigomicose/etiologia , Adolescente , Adulto , Idoso , Anfotericina B/uso terapêutico , Criança , Pré-Escolar , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Voriconazol
16.
J Med Genet ; 43(4): 334-9, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16155189

RESUMO

BACKGROUND: Joubert syndrome (JS) is an autosomal recessive disorder characterised by hypotonia, ataxia, mental retardation, altered respiratory pattern, abnormal eye movements, and a brain malformation known as the molar tooth sign (MTS) on cranial MRI. Four genetic loci have been mapped, with two genes identified (AHI1 and NPHP1). METHODS: We screened a cohort of 117 JS subjects for AHI1 mutations by a combination of haplotype analysis and sequencing of the gene, and for the homozygous NPHP1 deletion by sequencing and marker analysis. RESULTS: We identified a total of 15 novel AHI1 mutations in 13 families, including nonsense, missense, splice site, and insertion mutations, with some clustering in the WD40 domains. Eight families were consanguineous, but no single founder mutation was apparent. In addition to the MTS, retinal dystrophy was present in 11 of 12 informative families; however, no subjects exhibited variable features of JS such as polydactyly, encephalocele, colobomas, or liver fibrosis. In contrast to previous reports, we identified two families with affected siblings who developed renal disease consistent with nephronophthisis (NPH) in their 20s. In addition, two individuals with classic NPH were found to have homozygous NPHP1 deletions. CONCLUSIONS: Overall, 11% of subjects had AHI1 mutations, while approximately 2% had the NPHP1 deletion, representing a total of less than 15% in a large JS cohort. Some preliminary genotype-phenotype correlations are possible, notably the association of renal impairment, specifically NPH, in those with NPHP1 deletions. Subjects with AHI1 mutations may be at risk of developing both retinal dystrophy and progressive kidney disease.


Assuntos
Anormalidades Múltiplas/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Tronco Encefálico/anormalidades , Cerebelo/anormalidades , Doenças Renais Císticas/genética , Mutação , Degeneração Retiniana/genética , Anormalidades Múltiplas/diagnóstico , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transporte Vesicular , Motivos de Aminoácidos , Estudos de Coortes , Proteínas do Citoesqueleto , Feminino , Humanos , Doenças Renais Císticas/diagnóstico , Masculino , Proteínas de Membrana , Linhagem , Proteínas/genética , Degeneração Retiniana/diagnóstico , Síndrome
17.
J Natl Cancer Inst ; 93(16): 1204-14, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11504766

RESUMO

Epoetin treatment offers an attractive but costly alternative to red blood cell transfusion for managing anemia associated with cancer therapy. The goal of this review is to facilitate more efficient use of epoetin by 1) quantifying the effects of epoetin on the likelihood of transfusion and on quality of life in patients with cancer treatment-related anemia and 2) evaluating whether outcomes are superior when epoetin treatment is initiated at higher hemoglobin thresholds. Two independent reviewers followed a prospective protocol for identifying studies. Outcomes data were combined with the use of a random-effects meta-analysis model. Double-blind, randomized, controlled trials that minimized patient exclusions were defined as higher quality for sensitivity analysis; randomized but unblinded trials and trials with excessive exclusions were included in the meta-analysis but were defined as lower quality. Twenty-two trials (n = 1927) met inclusion criteria, and 12 (n = 1390) could be combined for estimation of odds of transfusion. Epoetin decreased the percentage of patients transfused by 9%-45% in adults with mean baseline hemoglobin concentrations of 10 g/dL or less (seven trials; n = 1080), by 7%-47% in those with hemoglobin concentrations greater than 10 g/dL but less than 12 g/dL (seven trials; n = 431), and by 7%-39% in those with hemoglobin concentrations of 12 g/dL or higher (five trials; n = 308). In sensitivity analysis, the combined odds ratio for transfusion in epoetin-treated patients as compared with controls was 0.45 (95% confidence interval [CI] = 0.33 to 0.62) in higher quality studies and 0.14 (95% CI = 0.06 to 0.31) in lower quality studies. The number of patients needed to treat to prevent one transfusion is 4.4 for all studies, 5.2 for higher quality studies, and 2.6 for lower quality studies. Only studies with mean baseline hemoglobin concentrations of 10 g/dL or less reported statistically significant effects of epoetin treatment on quality of life; quality-of-life data were insufficient for meta-analysis. No studies addressed epoetin's effects on anemia-related symptoms. We conclude that epoetin reduces the odds of transfusion for cancer patients undergoing therapy. Evidence is insufficient to determine whether initiating epoetin earlier spares more patients from transfusion or results in better quality of life than waiting until hemoglobin concentrations decline to nearly 10 g/dL.


Assuntos
Anemia/tratamento farmacológico , Eritropoetina/uso terapêutico , Hematínicos/uso terapêutico , Neoplasias/terapia , Anemia/etiologia , Antineoplásicos/efeitos adversos , Transfusão de Sangue/estatística & dados numéricos , Ensaios Clínicos Controlados como Assunto , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Razão de Chances , Qualidade de Vida , Radioterapia/efeitos adversos , Projetos de Pesquisa , Sensibilidade e Especificidade
18.
Cancer Res ; 47(7): 1952-6, 1987 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-3815383

RESUMO

Etoposide (VP-16) is a semisynthetic epipodophyllotoxin that exhibits cell cycle phase specific cytotoxicity and enhanced effectiveness with increasing duration of drug exposure. We have therefore conducted a Phase I trial to determine the side effects, tolerable doses, and pharmacokinetic parameters of VP-16 given by continuous i.v. infusion to patients with advanced cancer. Eighteen patients were treated with varying dosages of VP-16 infused continuously for 72 consecutive hours every 28 days. Using this schedule, the maximally tolerated dosage of VP-16 was 150 mg/m2/day for patients with good performance status and 125 mg/m2/day for more debilitated cancer patients. Hematological toxicity was dose limiting with median granulocyte and platelet nadirs of 700/mm3 and 116,000/mm3, respectively, at a dose of 150 mg/m2/day. Other toxicities included only mild nausea, vomiting, and alopecia. Plasma and urine VP-16 concentrations were determined using a high-performance liquid chromatography assay. At a VP-16 dosage of 150 mg/m2/day, steady-state VP-16 concentrations were in the range of 2.1 to 7.0 micrograms/ml in all patients. Further pharmacokinetic analysis revealed that the plasma clearance of VP-16 was consistently near 25 ml/min/m2 (independent of dosage) and that renal clearance accounted for only 15% of VP-16 total plasma clearance. Patient age was found to be the most important factor correlating with plasma clearance of VP-16. Linear regression analysis also revealed that both the plasma VP-16 concentration at steady state and the concentration of VP-16 in plasma at 24 h from the start of the infusion correlated with hematological toxicity; no other patient characteristics correlated with hematological toxicity. The recommended VP-16 dose for Phase II trials of 72-h continuous infusion VP-16 is 150 mg/m2/day in patients with good performance status.


Assuntos
Etoposídeo/toxicidade , Adulto , Idoso , Criança , Avaliação de Medicamentos , Etoposídeo/administração & dosagem , Etoposídeo/uso terapêutico , Feminino , Humanos , Infusões Intravenosas , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade
19.
Bone Marrow Transplant ; 51(2): 277-82, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26524262

RESUMO

Risk factors for non-Aspergillus mold infection (NAMI) and the impact on transplant outcome are poorly assessed in the current era of antifungal agents. Outcomes of 124 patients receiving allogeneic hematopoietic cell transplantation (HCT) diagnosed with either mucormycosis (n=72) or fusariosis (n=52) between days 0 and 365 after HCT are described and compared with a control cohort (n=11 856). Patients with NAMI had more advanced disease (mucormycois: 25%, fusariosis: 23% and controls: 18%; P=0.004) and were more likely to have a Karnofsky performance status (KPS) <90% at HCT (mucormycosis: 42%, fusariosis: 38% and controls: 28%; P=0.048). The 1-year survival after HCT was 22% (15-29%) for cases and was significantly inferior compared with controls (65% (64-65%); P<0.001). Survival from infection was similarly dismal regardless of mucormycosis: 15% (8-25%) and fusariosis: 21% (11-33%). In multivariable analysis, NAMI was associated with a sixfold higher risk of death (P<0.0001) regardless of the site or timing of infection. Risk factors for mucormycosis include preceding acute GvHD, prior Aspergillus infection and older age. For fusariosis, increased risks including receipt of cord blood, prior CMV infection and transplant before May 2002. In conclusion, NAMI occurs infrequently, is associated with high mortality and appears with similar frequency in the current antifungal era.


Assuntos
Fusariose , Transplante de Células-Tronco Hematopoéticas , Mucormicose , Doença Aguda , Adolescente , Adulto , Fatores Etários , Idoso , Aloenxertos , Aspergillus , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Fusariose/etiologia , Fusariose/mortalidade , Fusariose/terapia , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Mucormicose/etiologia , Mucormicose/mortalidade , Mucormicose/terapia , Fatores de Risco , Taxa de Sobrevida
20.
Circulation ; 102(23): 2810-5, 2000 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-11104737

RESUMO

BACKGROUND: The basis for progressive attenuation of the effects of organic nitrates during long-term therapy (nitrate tolerance) remains controversial; proposed mechanisms include impaired nitrate bioconversion resulting in decreased release of nitric oxide (NO) from nitrates and/or increased NO clearance through a reaction with incrementally generated superoxide (O(2)(-)). METHODS AND RESULTS: Patients undergoing elective coronary artery bypass were randomized to receive 24 hours of intravenously infused nitroglycerin (NTG; nitrate group) or no nitrate therapy (control group). Discarded segments of the internal mammary artery and saphenous vein were used to examine (1) vascular responsiveness to NTG, sodium nitroprusside, and the calcium ionophore A23187; (2) bioconversion of NTG to 1,2- and 1,3-glyceryl dinitrate; and (3) the generation of O(2)(-). Responses to NTG were reduced 3- to 5-fold in vessels from the nitrate group compared with control vessels (P:<0. 01 for both types of segments), whereas responses to sodium nitroprusside and A23187 were unchanged. Tissue content of 1, 2-glyceryl dinitrate was lower (P:=0.012) in the saphenous veins from the nitrate group than in those from the control group. O(2)(-) generation was greater (P:<0.01) in internal mammary artery samples from the nitrate group than in those from the control group. However, incremental O(2)(-) generation induced by an inhibitor of superoxide dismutase did not affect NTG responses. CONCLUSIONS: NTG tolerance in patients with coronary artery disease is nitrate-specific and is associated with evidence of impaired NTG bioconversion. Tolerance was associated with incremental O(2)(-) generation, but short-term elevation of O(2)(-) did not affect NTG responsiveness, suggesting increased NO clearance by O(2)(-) has a minimal contribution to tolerance.


Assuntos
Vasos Sanguíneos/efeitos dos fármacos , Nitroglicerina/análogos & derivados , Nitroglicerina/farmacologia , Vasos Sanguíneos/metabolismo , Doença das Coronárias/tratamento farmacológico , Doença das Coronárias/metabolismo , Doença das Coronárias/cirurgia , Tolerância a Medicamentos , Feminino , Humanos , Infusões Intravenosas , Masculino , Artéria Torácica Interna/efeitos dos fármacos , Artéria Torácica Interna/metabolismo , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Nitroglicerina/metabolismo , Nitroglicerina/farmacocinética , Nitroglicerina/uso terapêutico , Veia Safena/efeitos dos fármacos , Veia Safena/metabolismo , Superóxidos/metabolismo
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