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1.
Opt Lett ; 47(9): 2350-2353, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35486797

RESUMO

This work advances laser absorption spectroscopy with measurements of aluminum monoxide (AlO) temperature and column density in extreme pressure (P > 60 bar) and temperature (T > 4000 K) environments. Measurements of the AlO A2Πi-X2Σ+ transition are made using a microelectromechanical system, tunable vertical cavity surface emitting laser (MEMS-VCSEL). Simultaneous emission measurements of the AlO B2Σ+-X2Σ+ transition are made along a line of sight that is coaxial with the laser absorption. Absorption temperature fits agree with emission spectra for a T = 3200 K, P = 9 bar case. In cases with T > 4000 K, P > 60 bar, absorption fits match the ambient temperature while emission fits over-estimate it, owing to high optical depths. These data juxtapose passive and active spectroscopic methods and demonstrate the versatility of AlO laser absorption in high-pressure and high-temperature environments where experimental data remain scarce, and engineering models will benefit from refined measurements.

2.
Artigo em Inglês | MEDLINE | ID: mdl-35573857

RESUMO

Imaging phantoms are used to calibrate and validate the performance of magnetic resonance imaging (MRI) systems. Many new materials have been developed for additive manufacturing (three-dimensional [3D] printing) processes that may be useful in the direct printing or casting of dimensionally accurate, anatomically accurate, patient-specific, and/or biomimetic MRI phantoms. The T1, T2, and T2* spin relaxation times of polymer samples were tested to discover materials for use as tissue mimics and structures in MRI phantoms. This study included a cohort of polymer compounds that was tested in cured form. The cohort consisted of 101 standardized polymer samples fabricated from: two-part silicones and polyurethanes used in commercial casting processes; one-part optically cured polyurethanes used in 3D printing; and fused deposition thermoplastics used in 3D printing. The testing was performed at 3 T using inversion recovery, spin echo, and gradient echo sequences for T1, T2, and T2*, respectively. T1, T2, and T2* values were plotted with error bars to allow the reader to assess how well a polymer matches a tissue for a specific application. A correlation was performed between T1, T2, T2* values and material density, elongation, tensile strength, and hardness. Two silicones, SI_XP-643 and SI_P-45, may be usable mimics for reported liver values; one silicone, SI_XP-643, may be a useful mimic for muscle; one silicone, SI_XP-738, may be a useful mimic for white matter; and four silicones, SI_P-15, SI_GI-1000, SI_GI-1040, and SI_GI-1110, may be usable mimics for spinal cord. Elongation correlated to T2 (p = 0.0007), tensile strength correlated to T1 (p = 0.002), T2 (p = 0.0003), and T2* (p = 0.003). The 80 samples not providing measurable signal with T1, T2, T2* relaxation values too short to measure with the standard sequences, may be useful for MRI-invisible fixturing and medical devices at 3 T.

3.
J Cancer Educ ; 29(4): 698-701, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24633725

RESUMO

Several studies have found a link between health literacy and participation in cancer screening. Most, however, have relied on self-report to determine screening status. Further, until now, health literacy measures have assessed print literacy only. The purpose of this study was to examine the relationship between participation in cervical cancer screening (Papanicolaou [Pap] testing) and two forms of health literacy-reading and listening. A demographically diverse sample was recruited from a pool of insured women in Georgia, Massachusetts, Hawaii, and Colorado between June 2009 and April 2010. Health literacy was assessed using the Cancer Message Literacy Test-Listening and the Cancer Message Literacy Test-Reading. Adherence to cervical cancer screening was ascertained through electronic administrative data on Pap test utilization. The relationship between health literacy and adherence to evidence-based recommendations for Pap testing was examined using multivariate logistic regression models. Data from 527 women aged 40 to 65 were analyzed and are reported here. Of these 527 women, 397 (75 %) were up to date with Pap testing. Higher health literacy scores for listening but not reading predicted being up to date. The fact that health literacy listening was associated with screening behavior even in this insured population suggests that it has independent effects beyond those of access to care. Patients who have difficulty understanding spoken recommendations about cancer screening may be at risk for underutilizing screening as a result.


Assuntos
Detecção Precoce de Câncer/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Letramento em Saúde , Seguro Saúde , Teste de Papanicolaou/estatística & dados numéricos , Neoplasias do Colo do Útero/prevenção & controle , Esfregaço Vaginal , Adulto , Idoso , Feminino , Seguimentos , Acessibilidade aos Serviços de Saúde , Humanos , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Inquéritos e Questionários , Neoplasias do Colo do Útero/psicologia
4.
Science ; 243(4887): 66-9, 1989 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-17780424

RESUMO

Evidence suggests that superconducting, orthorhombic YBa(2)Cu(3)O(6+x)+ (x greater, similar 0.5) is always produced by oxidation of the oxygen-deficient, tetragonal form (x less, similar 0.5) of this phase (commonly referred to as 123). A synthetic route whereby solution-derived, carbon-free precursors are decomposed at 650 degrees to 700 degrees C in inert atmosphere to yield tetragonal 123 is now available. Appropriate precursors include hydrated oxides derived from the hydrolysis of organometallic solutions and aqueous solution-derived hyponitrites. Subsequent oxidation of the tetragonal phase at 400 degrees C results in submicrometer particles of orthorhombic 123. Superconductivity (T(c) onset approximately 87 K) has been confirmed in these materials by both Meissner effect and specific-heat measurements.

5.
J Natl Cancer Inst ; 91(10): 847-53, 1999 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-10340904

RESUMO

BACKGROUND: Payment for care provided as part of clinical research has become less predictable as a result of managed care. Because little is known at present about how entry into cancer trials affects the cost of care for cancer patients, we conducted a matched case-control comparison of the incremental medical costs attributable to participation in cancer treatment trials. METHODS: Case patients were residents of Olmsted County, MN, who entered phase II or phase III cancer treatment trials at the Mayo Clinic from 1988 through 1994. Control patients were patients who did not enter trials but who were eligible on the basis of tumor registry matching and medical record review. Sixty-one matched pairs were followed for up to 5 years after the date of trial entry for case patients or from an equivalent date for control patients. Hospital, physician, and ancillary service costs were estimated from a population-based cost database developed at the Mayo Clinic. RESULTS: Trial enrollees incurred modestly (no more than 10%) higher costs over various follow-up periods. The mean cumulative 5-year cost in 1995 inflation-adjusted U.S. dollars among trial enrollees after adjustment for censoring was $46424 compared with $44 133 for control patients. After 1 year, trial enrollee costs were $24645 compared with $23 964 for control patients. CONCLUSIONS: This study suggests that cancer chemotherapy trials may not imply budget-breaking costs. Cancer itself is a high-cost illness. Clinical protocols may add relatively little to that cost.


Assuntos
Institutos de Câncer/economia , Ensaios Clínicos como Assunto/economia , Neoplasias/economia , Estudos de Casos e Controles , Ensaios Clínicos Fase II como Assunto/economia , Ensaios Clínicos Fase III como Assunto/economia , Feminino , Custos Hospitalares , Hospitais de Prática de Grupo/economia , Humanos , Masculino , Análise por Pareamento , Minnesota , Neoplasias/terapia , Seleção de Pacientes , Estados Unidos
6.
Diabetes ; 48(7): 1473-81, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10389857

RESUMO

Clinical islet cell transplantation has resulted in insulin independence in a limited number of cases. Rejection, recurrence of autoimmunity, and impairment of normal islet function by conventional immunosuppressive drugs, e.g., steroids, tacrolimus, and cyclosporin A, may all contribute to islet allograft loss. Furthermore, intraportal infusion of allogeneic islets results in the activation of intrahepatic macrophages and endothelial cells, followed by production of proinflammatory mediators that can contribute to islet primary nonfunction. We reasoned that the beneficial effects of anti-CD154 treatment on autoimmunity, alloreactivity, and proinflammatory events mediated by macrophages and endothelial cells made it an ideal agent for the prevention of islet allograft failure. In this study, a nonhuman primate model (Papio hamadryas) was used to assess the effect of humanized anti-CD154 (hu5c8) on allogeneic islet engraftment and function. Nonimmunosuppressed and tacrolimus-treated recipients were insulin independent posttransplant, but rejected their islet allografts in 8 days. Engraftment and insulin independence were achieved in seven of seven baboon recipients of anti-CD154 induction therapy administered on days -1, 3, and 10 relative to the islet transplant. Three of three baboons treated with 20 mg/kg anti-CD154 induction therapy experienced delayed rejection episodes, first detected by elevations in postprandial blood glucose levels, on postoperative day (POD) 31 for one and on POD 58 for the other two. Re-treatment with three doses of anti-CD154 resulted in reversal of rejection in all three animals and in a return to normoglycemia and insulin independence in two of three baboons. It was possible to reverse multiple episodes of rejection with this approach. A loss of functional islet mass, as detected by reduced first-phase insulin release in response to intravenous glucose tolerance testing, was observed after each episode of rejection. One of two baboons treated with 10 mg/kg induction therapy became insulin independent post-transplant but rejected the islet graft on POD 10; the other animal experienced a reversible rejection episode on POD 58 and remained insulin independent and normoglycemic until POD 264. Two additional baboon recipients of allogeneic islets and donor bone marrow (infused on PODs 5 and 11) were treated with induction therapy (PODs -1, 3, 10), followed by initiation of monthly maintenance therapy (for a period of 6 months) on POD 28. Rejection-free graft survival and insulin independence was maintained for 114 and 238 days, with preservation of functional islet mass observed in the absence of rejection. Prevention and reversal of rejection, in the absence of the deleterious effects associated with the use of conventional immunosuppressive drugs, make anti-CD154 a unique agent for further study in islet cell transplantation.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Sobrevivência de Enxerto , Transplante das Ilhotas Pancreáticas , Fígado/cirurgia , Glicoproteínas de Membrana/imunologia , Animais , Ligante de CD40 , Feminino , Humanos , Masculino , Papio , Período Pós-Operatório , Fatores de Tempo , Transplante Homólogo
7.
Arch Intern Med ; 151(6): 1089-95, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1904212

RESUMO

To predict the consequences of cholesterol screening among elderly Americans who do not have symptoms of heart disease, we explore the cost implications of a cholesterol screening program, evaluate evidence linking hypercholesterolemia to coronary heart disease and mortality in the elderly, and describe the likely effects of therapy of hypercholesterolemia. According to our calculations, if all Americans 65 years of age and older adhered to a cholesterol screening program similar to the one proposed by the National Cholesterol Education Program, minimum annual expenditures for screening and treatment would be between $1.6 billion and $16.8 billion, depending on the effectiveness of diet and the cost of the medications used to treat hypercholesterolemia. There is no direct evidence that this program would lessen overall morbidity or extend the lives of elderly Americans.


Assuntos
Gastos em Saúde/estatística & dados numéricos , Cardiopatias/prevenção & controle , Hipercolesterolemia/prevenção & controle , Programas de Rastreamento/economia , Idoso , Custos e Análise de Custo , Feminino , Cardiopatias/mortalidade , Humanos , Masculino , Neoplasias/mortalidade , Fatores de Risco , Taxa de Sobrevida , Estados Unidos
8.
Bone Marrow Transplant ; 50(12): 1513-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26301967

RESUMO

In patients with multiple myeloma (MM) undergoing autologous hematopoietic cell transplantation (auto-HCT), peripheral blood progenitor cells may be collected following mobilization with growth factor alone (GF) or cytotoxic chemotherapy plus GF (CC+GF). It is uncertain whether the method of mobilization affects post-transplant outcomes. We compared these mobilization strategies in a retrospective analysis of 968 patients with MM from the Center for International Blood and Marrow Transplant Research database who received an auto-HCT in the US and Canada between 2007 and 2012. The kinetics of neutrophil engraftment (⩾0.5 × 10(9)/L) was similar between groups (13 vs 13 days, P=0.69) while platelet engraftment (⩾20 × 10(9)/L) was slightly faster with CC+GF (19 vs 18 days, P=0.006). Adjusted 3-year PFS was 43% (95% confidence interval (CI) 38-48) in GF and 40% (95% CI 35-45) in CC+GF, P=0.33. Adjusted 3-year OS was 82% (95% CI 78-86) vs 80% (95% CI 75-84), P=0.43 and adjusted 5-year OS was 62% (95% CI 54-68) vs 60% (95% CI 52-67), P=0.76, for GF and CC+GF, respectively. We conclude that MM patients undergoing auto-HCT have similar outcomes irrespective of the method of mobilization and found no evidence that the addition of chemotherapy to mobilization contributes to disease control.


Assuntos
Mobilização de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo/sangue , Mieloma Múltiplo/terapia , Adolescente , Adulto , Idoso , Autoenxertos , Intervalo Livre de Doença , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Estudos Prospectivos , Recuperação de Função Fisiológica , Taxa de Sobrevida
9.
J Interferon Cytokine Res ; 16(8): 611-7, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8877732

RESUMO

A novel cytokine originally designated murine CTLA-8 was described as a cDNA isolated from an activated T cell hybridoma produced by fusing a mouse cytotoxic T cell clone and a rat T lymphoma. This cDNA, which contains mRNA instability sequences characteristic of many cytokines, encoded a putative secreted protein that was homologous to the ORF13 gene of Herpesvirus saimiri. The human homolog to this molecule has recently been identified as the proinflammatory cytokine IL-17. We describe the isolation of a cDNA encoding mouse IL-17 from a cDNA library generated from alpha beta TCR + CD4-CD8- thymocytes using a subtraction technique that enriched for activation specific genes. This cDNA shares 87.3% amino acid identity to the previously described murine CTLA-8. Comparison of murine CTLA-8 to a cDNA we isolated from activated rat splenocytes revealed that murine CTLA-8 is, in fact, the rat homolog of IL-17. Mouse IL-17 mRNA is specifically expressed by activated alpha beta TCR + CD4-CD8- T cells, a small subset with a potentially important role in immune regulation. Mouse, rat, and human IL-17 can induce IL-6 secretion in mouse stromal cells, indicating that all homologs can recognize the mouse receptor.


Assuntos
Interleucinas/genética , Camundongos/genética , Receptores de Antígenos de Linfócitos T alfa-beta/análise , Subpopulações de Linfócitos T/metabolismo , Animais , Células da Medula Óssea , Tecido Conjuntivo/efeitos dos fármacos , Tecido Conjuntivo/metabolismo , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Biblioteca Gênica , Genes , Humanos , Interleucina-17 , Interleucina-6/metabolismo , Interleucinas/biossíntese , Interleucinas/farmacologia , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Ratos , Proteínas Recombinantes de Fusão/farmacologia , Alinhamento de Sequência , Homologia de Sequência , Especificidade da Espécie , Técnica de Subtração , Células Tumorais Cultivadas
10.
Transplantation ; 62(6): 876-7, 1996 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-8824495

RESUMO

The dog has served traditionally as a model for marrow and organ transplantation. A key component of any study of transplantation is histocompatibility typing of donors and recipients. Towards the development of a less expensive, more simplified typing system within canine families, a new highly polymorphic microsatellite marker for the canine Major Histocompatibility Complex class II region was isolated and characterized. In addition, we report on the application of class I and class II microsatellite-based markers for following the inheritance of the alleles within the canine analog of the human HLA loci, DLA, through multi-generation pedigree.


Assuntos
Cães/imunologia , Teste de Histocompatibilidade/veterinária , Complexo Principal de Histocompatibilidade/genética , Repetições de Microssatélites , Alelos , Animais , Cães/genética , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo Genético
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