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1.
Entropy (Basel) ; 24(9)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36141154

RESUMO

We present a critique of the many-world interpretation of quantum mechanics, based on different "pictures" that describe the time evolution of an isolated quantum system. Without an externally imposed frame to restrict these possible pictures, the theory cannot yield non-trivial interpretational statements. This is analogous to Goodman's famous "grue-bleen" problem of language and induction. Using a general framework applicable to many kinds of dynamical theories, we try to identify the kind of additional structure (if any) required for the meaningful interpretation of a theory. We find that the "grue-bleen" problem is not restricted to quantum mechanics, but also affects other theories including classical Hamiltonian mechanics. For all such theories, absent external frame information, an isolated system has no interpretation.

2.
Entropy (Basel) ; 20(4)2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33265328

RESUMO

We present an axiomatic framework for thermodynamics that incorporates information as a fundamental concept. The axioms describe both ordinary thermodynamic processes and those in which information is acquired, used and erased, as in the operation of Maxwell's demon. This system, similar to previous axiomatic systems for thermodynamics, supports the construction of conserved quantities and an entropy function governing state changes. Here, however, the entropy exhibits both information and thermodynamic aspects. Although our axioms are not based upon probabilistic concepts, a natural and highly useful concept of probability emerges from the entropy function itself. Our abstract system has many models, including both classical and quantum examples.

3.
J Oncol Pharm Pract ; 24(5): 365-370, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28554241

RESUMO

Purpose Reduction in waste of intravenous (IV) tacrolimus, an immunosuppressant used to prevent graft-versus-host disease in allogeneic hematopoietic stem cell transplantation recipients, was evaluated after standardizing the concentration. Methods A single-center, retrospective cohort study at a large academic comprehensive cancer center was performed comparing patient-specific intravenous tacrolimus doses (tacrolimus doses in 50, 100, or 250 mL of normal saline based on manufacturer's recommended concentration) to tacrolimus intravenous standard concentration (tacrolimus 1 mg in 250 mL of normal saline) continuous intravenous infusion titrated to prescribed dose. The cohort study was performed on two hematopoietic stem cell transplantation nursing units consisting of a prepilot phase during which time patient-specific intravenous tacrolimus doses were compounded and administered, followed by the pilot phase during which patients received tacrolimus intravenous standard concentration. The primary endpoint was reduction in tacrolimus intravenous bags wasted. Secondary endpoints were drug cost savings, decreased intravenous infusion line supplies, decrease in time needed to execute dose changes, reduction in infusion pump alerts, and number of patient safety events. Results Compared to the prepilot phase, there was a 64% reduction in tacrolimus intravenous bags wasted during the pilot phase ( p = 0.029), resulting in a mean monthly total cost savings of $224.31 for pilot units. Intravenous pump line use was reduced by 18% ( p = 0.067), yielding a monthly total cost savings of $84.02 for pilot units. The median time needed to execute dose changes and intravenous pump overrides was significantly reduced ( p < 0.0001, p < 0.0001, respectively). Conclusion This interdisciplinary quality improvement initiative led to increased efficiency, reduction in waste, and decreased intravenous pump alerts utilizing tacrolimus intravenous standard concentration.


Assuntos
Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/métodos , Imunossupressores/administração & dosagem , Tacrolimo/administração & dosagem , Adulto , Humanos , Imunossupressores/uso terapêutico , Infusões Intravenosas , Projetos Piloto , Estudos Retrospectivos
4.
Biol Blood Marrow Transplant ; 22(3): 564-570, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26718665

RESUMO

The American Society for Blood and Marrow Transplantation (ASBMT) Clinical Case Forum (CCF) was launched in 2014 as an online secure tool to enhance interaction and communication among hematopoietic cell transplantation (HCT) professionals worldwide through the discussion of challenging clinical care issues. After 14 months, we reviewed clinical and demographical data of cases posted in the CCF from January 29, 2014 to March 18, 2015. A total of 137 cases were posted during the study period. Ninety-two cases (67%) were allogeneic HCT, 29 (21%) were autologous HCT, and in 16 (12%), the type of transplantation (autologous versus allogeneic) was still under consideration. The diseases most frequently discussed included non-Hodgkin lymphoma (NHL; n = 30, 22%), acute myeloid leukemia (n = 23, 17%), and multiple myeloma (MM; n = 20, 15%). When compared with the US transplantation activity reported by the US Department of Health and Human Services, NHL and acute lymphoblastic leukemia cases were over-represented in the CCF, whereas MM was under-represented (P < .001). A total of 259 topics were addressed in the CCF with a median of 2 topics/case (range, 1 to 6). Particularly common topics included whether transplantation was indicated (n = 57, 41%), conditioning regimen choice (n = 44, 32%), and post-HCT complications after day 100 (n = 43, 31%). The ASBMT CCF is a successful tool for collaborative discussion of complex cases in the HCT community worldwide and may allow identification of areas of controversy or unmet need from clinical, educational and research perspectives.


Assuntos
Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas , Sociedades Médicas , Aloenxertos , Autoenxertos , Humanos , Estados Unidos
5.
J Oncol Pharm Pract ; 22(2): 325-31, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25488905

RESUMO

Cidofovir, a nucleoside analog of deoxycytidine monophosphate, is a water-soluble polar molecule that exhibits antiviral activity against a broad range of DNA viruses. Cidofovir for injection is approved for the treatment of cytomegalovirus retinitis in patients with acquired immune deficiency syndrome. The safety and efficacy of topical cidofovir has been described in a limited number of patients. We present two cases of multidrug-resistant herpes simplex virus infections that responded to topical cidofovir therapy yet resulted in irreversible acute kidney injury.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Antivirais/efeitos adversos , Citosina/análogos & derivados , Farmacorresistência Viral Múltipla/efeitos dos fármacos , Herpes Simples/tratamento farmacológico , Hospedeiro Imunocomprometido/efeitos dos fármacos , Organofosfonatos/efeitos adversos , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/imunologia , Administração Tópica , Antivirais/administração & dosagem , Cidofovir , Citosina/administração & dosagem , Citosina/efeitos adversos , Farmacorresistência Viral Múltipla/imunologia , Herpes Simples/diagnóstico , Herpes Simples/imunologia , Humanos , Hospedeiro Imunocomprometido/imunologia , Masculino , Pessoa de Meia-Idade , Organofosfonatos/administração & dosagem
6.
J Oncol Pharm Pract ; 20(4): 257-62, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24022408

RESUMO

Cytomegalovirus reactivation is a common complication of allogeneic hematopoietic stem cell transplant. The use of pre-transplant valganciclovir during the conditioning regimen followed by preemptive therapy has been used in an attempt to reduce the rate of early cytomegalovirus reactivation, but efficacy data are lacking. In this retrospective study, we evaluated the impact of pre-transplant valganciclovir during the conditioning regimen followed by a preemptive approach on the rate of early cytomegalovirus reactivation through day 100. The rate of cytomegalovirus reactivation through day 100 was 41% in the no-valganciclovir group compared to 46% in the valganciclovir group (p = 0.4). Interestingly, median time to cytomegalovirus reactivation was earlier in the no-valganciclovir group compared to the valganciclovir group (26 vs. 34 days; p = 0.008) and there was a trend toward a higher rate of cytomegalovirus disease through day 100 in the no-valganciclovir group (0.7% valganciclovir vs. 4% no-valganciclovir; p = 0.1). Day 100 survival was similar between the groups (90% valganciclovir vs. 91% no-valganciclovir; p = 0.8). Although the time to cytomegalovirus reactivation is significantly longer in the valganciclovir group, this did not impact the rate of cytomegalovirus reactivation or survival by day 100 suggesting that other strategies need to be explored.


Assuntos
Antivirais/uso terapêutico , Infecções por Citomegalovirus/prevenção & controle , Ganciclovir/análogos & derivados , Transplante de Células-Tronco Hematopoéticas/métodos , Adulto , Idoso , Feminino , Ganciclovir/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Condicionamento Pré-Transplante/métodos , Transplante Homólogo , Valganciclovir , Adulto Jovem
7.
J Natl Compr Canc Netw ; 11(10): 1266-90, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24142827

RESUMO

Febrile neutropenia, a common side effect of myelosuppressive chemotherapy in patients with cancer, can result in prolonged hospitalization and broad-spectrum antibiotic use, often prompting treatment delays or dose reductions of drug regimens. Prophylactic use of myeloid growth factors (mainly the colony-stimulating factors filgrastim and pegfilgrastim) in patients of heightened risk can reduce the severity and duration of febrile neutropenia. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Myeloid Growth Factors provide recommendations on the use of these agents mainly in the oncology setting based on clinical evidence and expert consensus. This version includes revisions surrounding the issue of timing of pegfilgrastim administration. It also includes new sections on tbo-filgrastim, a recently approved agent that is biologically similar to filgrastim, and the role of myeloid growth factors in the hematopoietic cell transplant setting.


Assuntos
Neutropenia Febril Induzida por Quimioterapia/tratamento farmacológico , Fatores Estimuladores de Colônias/uso terapêutico , Neutropenia Febril Induzida por Quimioterapia/prevenção & controle , Doença Crônica , Fatores Estimuladores de Colônias/administração & dosagem , Fatores Estimuladores de Colônias/efeitos adversos , Mobilização de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Hematopoéticas , Humanos , Neutropenia/tratamento farmacológico , Neutropenia/etiologia , Pré-Medicação , Resultado do Tratamento
9.
J Clin Oncol ; 29(3): 294-302, 2011 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-21149654

RESUMO

PURPOSE: Acute graft-versus-host disease (aGVHD) is a major cause of morbidity and mortality after matched unrelated, related, or mismatched related donor hematopoietic stem-cell transplantation (HSCT). Improved GVHD prevention methods are needed. Pentostatin, an adenosine deaminase inhibitor, leads to lymphocyte depletion with low risk of myelosuppression. We hypothesized that addition of pentostatin to GVHD prophylaxis with tacrolimus and mini-methotrexate may improve outcomes, and we conducted a Bayesian adaptively randomized, controlled, dose-finding study, taking into account toxicity and efficacy. PATIENTS AND METHODS: Success was defined as the patient being alive, engrafted, in remission, without GVHD 100 days post-HSCT and no grade ≥ 3 GVHD at any time. Patients were randomly assigned to pentostatin doses of 0, 0.5, 1.0, 1.5, and 2.0 mg/m(2) with drug administered on HSCT days 8, 15, 22, and 30. Eligible patients were recipients of mismatched related (n = 10) or unrelated (n = 137) donor HSCT. RESULTS: Median age was 47 years. Thirty-seven, 10, 29, 61, and 10 patients were assigned to the control and four treatment groups, respectively, with comparable baseline characteristics. Pentostatin doses of 1.0 and 1.5 mg/m(2) had the highest success rates (69.0% and 70.5%) versus control (54.1%). The posterior probabilities that the success rates were greater with 1.5 mg/m(2) or 1.0 mg/m(2) versus control are 0.944 and 0.821, respectively. Hepatic aGVHD rates were 0%, 17.2%, and 11.1%, respectively, for 1.5 mg/m(2), 1.0 mg/m(2), and control groups. No grades 3 to 4 aGVHD occurred in 11 HLA-mismatched recipients in the 1.5 mg/m(2) group. CONCLUSION: Pentostatin increased the likelihood of success as defined here, and should be further investigated in larger randomized, confirmatory studies.


Assuntos
Inibidores de Adenosina Desaminase/administração & dosagem , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas , Imunossupressores/administração & dosagem , Pentostatina/administração & dosagem , Condicionamento Pré-Transplante/métodos , Inibidores de Adenosina Desaminase/efeitos adversos , Inibidores de Adenosina Desaminase/farmacologia , Adolescente , Adulto , Idoso , Relação Dose-Resposta a Droga , Esquema de Medicação , Quimioterapia Combinada , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/farmacologia , Análise de Intenção de Tratamento , Masculino , Metotrexato/administração & dosagem , Metotrexato/efeitos adversos , Metotrexato/farmacologia , Pessoa de Meia-Idade , Pentostatina/efeitos adversos , Pentostatina/farmacologia , Análise de Sobrevida , Tacrolimo/administração & dosagem , Tacrolimo/efeitos adversos , Tacrolimo/farmacologia
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