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BACKGROUND: Cytomegalovirus (CMV) commonly reactivates after allogeneic hematopoietic cell transplant (HCT), potentially leading to CMV disease and significant morbidity and mortality. To reduce morbidity and mortality, many centers conduct weekly CMV blood polymerase chain reaction (PCR) surveillance testing with subsequent initiation of antiviral therapy upon CMV DNAemia detection. However, the impact of CMV DNAemia on subsequent hospitalization risk has not been assessed using models accounting for the time-varying nature of the exposure, outcome, and confounders. METHODS: All allogeneic HCTs at the Children's Hospital of Philadelphia from January 2004-April 2017 were considered for inclusion. Patients were monitored with CMV surveillance via PCR testing for up to 105 days after HCT receipt. We estimated the association between CMV DNAemia and rate of hospitalization using marginal structural models (MSM). RESULTS: There were 343 allogeneic HCT episodes in 330 with CMV surveillance; median age was 9.0 (range: 0.1-26.2) and 46.5% were female. And 24.1% of HCT patients had at least one positive CMV blood PCR during the follow-up period. Median time to CMV DNAemia detection was 19 days (range: 4-97). The MSM estimated the incidence rate ratios for an association of CMV DNAemia with hospitalization to be 1.24, (95% confidence interval: 1.04-1.47). CONCLUSIONS: CMV DNAemia was associated with an increased hospitalization in the post-HCT period. The MSM accounted for time-varying nature of the outcome, exposure and confounders. The findings support prevention of CMV DNAemia in this population. We recommend further investigation into the effectiveness and safety of prophylaxis versus pre-emptive CMV prevention approaches.
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Infecções por Citomegalovirus , Transplante de Células-Tronco Hematopoéticas , Criança , Humanos , Feminino , Masculino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante Homólogo/efeitos adversos , DNA Viral , Infecções por Citomegalovirus/diagnóstico , Citomegalovirus , Antivirais/uso terapêutico , Estudos RetrospectivosRESUMO
Hematopoietic cell transplantation (HCT) is an established cure for sickle cell disease (SCD) supported by long-term survival, but long-term organ function data are lacking. We sought to describe organ function and assess predictors for dysfunction in a retrospective cohort (n = 247) through the Sickle cell Transplant Advocacy and Research alliance. Patients with <1-year follow-up or graft rejection/second HCT were excluded. Organ function data were collected from last follow-up. Primary measures were organ function, comparing pre- and post-HCT. Bivariable and multivariable analyses were performed for predictors of dysfunction. Median age at HCT was 9.4 years; the majority had HbSS (88.2%) and severe clinical phenotype (65.4%). Most received matched related (76.9%) bone marrow (83.3%) with myeloablative conditioning (MAC; 57.1%). Acute and chronic graft-versus-host disease (GVHD) developed in 24.0% and 24.8%. Thirteen patients (5.3%) died ≥1 year after HCT, primarily from GVHD or infection. More post-HCT patients had low ejection or shortening fractions than pre-HCT (0.6% â 6.0%, P = .007 and 0% â 4.6%, P = .003). The proportion with lung disease remained stable. Eight patients (3.2%) had overt stroke; most had normal (28.3%) or stable (50.3%) brain magnetic resonance imaging. On multivariable analysis, cardiac dysfunction was associated with MAC (odds ratio [OR] = 2.71; 95% confidence interval [CI], 1.09-6.77; P = .033) and severe acute GVHD (OR = 2.41; 95% CI, 1.04-5.62; P = .041). Neurologic events were associated with central nervous system indication (OR = 2.88; 95% CI, 2.00-4.12; P < .001). Overall organ dysfunction was associated with age ≥16 years (OR = 2.26; 95% CI, 1.35-3.78; P = .002) and clinically severe disease (OR = 1.64; 95% CI, 1.02-2.63; P = .043). In conclusion, our results support consideration of HCT at younger age and use of less intense conditioning.
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Anemia Falciforme , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Humanos , Estudos Retrospectivos , Transplante Homólogo , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Anemia Falciforme/terapia , Anemia Falciforme/complicaçõesRESUMO
Fanconi anemia (FA), a genetic DNA repair disorder characterized by marrow failure and cancer susceptibility. In FA mice, metformin improves blood counts and delays tumor development. We conducted a single institution study of metformin in nondiabetic patients with FA to determine feasibility and tolerability of metformin treatment and to assess for improvement in blood counts. Fourteen of 15 patients with at least 1 cytopenia (hemoglobin < 10 g/dL; platelet count < 100 000 cells/µL; or an absolute neutrophil count < 1000 cells/µL) were eligible to receive metformin for 6 months. Median patient age was 9.4 years (range 6.0-26.5 ). Thirteen of 14 subjects (93%) tolerated maximal dosing for age; 1 subject had dose reduction for grade 2 gastrointestinal symptoms. No subjects developed hypoglycemia or metabolic acidosis. No subjects had dose interruptions caused by toxicity, and no grade 3 or higher adverse events attributed to metformin were observed. Hematologic response based on modified Myelodysplastic Syndrome International Working Group criteria was observed in 4 of 13 evaluable patients (30.8%; 90% confidence interval, 11.3-57.3). Median time to response was 84.5 days (range 71-128 days). Responses were noted in neutrophils (n = 3), platelets (n = 1), and red blood cells (n = 1). No subjects met criteria for disease progression or relapse during treatment. Correlative studies explored potential mechanisms of metformin activity in FA. Plasma proteomics showed reduction in inflammatory pathways with metformin. Metformin is safe and tolerable in nondiabetic patients with FA and may provide therapeutic benefit. This trial was registered at as #NCT03398824.
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Anemia de Fanconi , Metformina , Criança , Anemia de Fanconi/tratamento farmacológico , Anemia de Fanconi/genética , Humanos , Metformina/uso terapêutico , Adulto JovemRESUMO
Vascular complications such as bleeding due to gastrointestinal telangiectatic anomalies, pulmonary arteriovenous malformations, hepatopulmonary syndrome, and retinal vessel abnormalities are being reported in patients with telomere biology disorders (TBDs) more frequently than previously described. The international clinical care consortium of telomere-associated ailments and family support group Dyskeratosis Congenita Outreach, Inc. held a workshop on vascular abnormalities in the TBDs at the National Cancer Institute in October 2017. Clinicians and basic scientists reviewed current data on vascular complications, hypotheses for the underlying biology and developed new collaborations to address the etiology and clinical management of vascular complications in TBDs.
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Fístula Arteriovenosa , Artéria Pulmonar/anormalidades , Veias Pulmonares/anormalidades , Telangiectasia , Telômero , Animais , Fístula Arteriovenosa/genética , Fístula Arteriovenosa/metabolismo , Fístula Arteriovenosa/patologia , Educação , Humanos , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Veias Pulmonares/metabolismo , Veias Pulmonares/patologia , Telangiectasia/genética , Telangiectasia/metabolismo , Telangiectasia/patologia , Telômero/genética , Telômero/metabolismo , Telômero/patologiaRESUMO
The threat posed by severe congenital abnormalities related to Zika virus (ZKV) infection during pregnancy has turned development of a ZKV vaccine into an emergency. Recent work suggests that the cytotoxic T lymphocyte (CTL) response to infection is an important defense mechanism in response to ZKV. Here, we develop the rationale and strategy for a new approach to developing cytotoxic T lymphocyte (CTL) vaccines for ZKV flavivirus infection. The proposed approach is based on recent studies using a protein structure computer model for HIV epitope selection designed to select epitopes for CTL attack optimized for viruses that exhibit antigenic drift. Because naturally processed and presented human ZKV T cell epitopes have not yet been described, we identified predicted class I peptide sequences on ZKV matching previously identified DNV (Dengue) class I epitopes and by using a Major Histocompatibility Complex (MHC) binding prediction tool. A subset of those met the criteria for optimal CD8+ attack based on physical chemistry parameters determined by analysis of the ZKV protein structure encoded in open source Protein Data File (PDB) format files. We also identified candidate ZKV epitopes predicted to bind promiscuously to multiple HLA class II molecules that could provide help to the CTL responses. This work suggests that a CTL vaccine for ZKV may be possible even if ZKV exhibits significant antigenic drift. We have previously described a microsphere-based CTL vaccine platform capable of eliciting an immune response for class I epitopes in mice and are currently working toward in vivo testing of class I and class II epitope delivery directed against ZKV epitopes using the same microsphere-based vaccine.
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OBJECTIVES: In partnership with a large nonprofit healthcare insurer for the Mid-Atlantic region of the United States, we launched the first cancer clinical pathway in the United States in August 2008. Due to its early success with regard to savings and physician participation and compliance, a second-generation pathways program-the Oncology Medical Home-was piloted in 2011. This program offered a physician reimbursement model that shifted the source of revenue from drug reimbursement margin to professional charges for cognitive services (evaluation and management codes). We report our observations of the impact of that reimbursement model on physician prescribing behavior. STUDY DESIGN: This was a retrospective analysis. METHODS: A select group of practices that participated in the first-generation pathways program were invited to voluntarily participate in the Oncology Medical Home and its cognitive weighted reimbursement design. A matched control group was chosen from the first-generation pathways participants. Comparisons of physician behavior parameters were made pre- and postimplementation and between the Oncology Medical Home practices and the first-generation pathways control group. RESULTS: Physician behavior was not significantly modified by cognitive weighted reimbursement. No significant change in frequency of office visits for established patients was observed. No change in chemotherapy prescribing was observed. Observed increases in generic regimen use were no different than matched control. CONCLUSIONS: Observations from this oncology medical home pilot program suggest that reimbursement methodology alternatives to the prevailing fee-for-service may have less impact on prescribing behavior than has been conjectured. Future research is ongoing to validate these observations and assess additional influences on prescribing behavior.
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Atitude do Pessoal de Saúde , Institutos de Câncer/organização & administração , Uso de Medicamentos/economia , Assistência Centrada no Paciente/economia , Padrões de Prática Médica/economia , Mecanismo de Reembolso , Assistência Ambulatorial/economia , Assistência Ambulatorial/organização & administração , Antineoplásicos/administração & dosagem , Antineoplásicos/economia , Estudos Transversais , Uso de Medicamentos/estatística & dados numéricos , Planos de Pagamento por Serviço Prestado , Feminino , Custos de Cuidados de Saúde , Humanos , Masculino , Oncologia/economia , Oncologia/organização & administração , Assistência Centrada no Paciente/organização & administração , Padrões de Prática Médica/organização & administração , Estudos Retrospectivos , Estados UnidosRESUMO
Modification of physiochemical and structural properties of carbon-based materials through targeted functionalization is a useful way to improve the properties and performance of such catalyst materials. This work explores the incorporation of dopants, including nitrogen, iodine, and fluorine, into the carbon structure of highly-oriented pyrolytic graphite (HOPG) and its potential benefits on the stability of PtRu catalyst nanoparticles. Evaluation of the changes in the catalyst nanoparticle coverage and size as a function of implantation parameters reveals that carbon supports functionalized with a combination of nitrogen and fluorine provide the most beneficial interactions, resulting in suppressed particle coarsening and dissolution. Benefits of a carefully tuned support system modified with fluorine and nitrogen surpass those obtained with nitrogen (no fluorine) modification. Ion implantation of iodine into HOPG results in a consistent amount of structural damage to the carbon matrix, regardless of dose. For this modification, improvements in stability are similar to nitrogen modification; however, the benefit is only observed at higher dose conditions. This indicates that a mechanism different than the one associated with nitrogen may be responsible for the improved durability.
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This article reports the synthesis and performance of unsupported Ni(1-x)Zn(x) electrocatalysts for the oxidation of hydrazine in alkaline media. Characterization of these catalysts was achieved using XRD, SEM, and TEM to confirm phase compositions, crystal structures, and morphologies. High performance was observed for the α-Ni(0.87)Zn(0.13) and ß(1)-Ni(0.50)Zn(0.50) electrocatalysts with an onset potential of -0.15 V (vs. RHE) and a mass activity of 4000-3800 A g(cat)(-1) at 0.4 V (vs. RHE), respectively. Additionally, in situ IRRAS studies were conducted to understand the mechanism of oxidation. These results demonstrate the feasibility of Ni(1-x)Zn(x) catalysts for direct hydrazine anionic fuel cells.
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Aerossóis/química , Hidrazinas/química , Níquel/química , Zinco/química , Catálise , Fontes de Energia Elétrica , EletroquímicaRESUMO
The variation in hair coat and skin histology traits of Criollo Limonero cattle was analyzed using 213 Criollo Limonero females. Skin biopsies were obtained from slick-haired (N=16) and normal-haired (N=14) animals. Measured traits included hair length (HL), color coat (CC), number of hair follicles per square centimeter (NHF), sweat glands per square centimeter (NSG), sweat glands size (SGS), sebaceous glands per square centimeter (NSBG), blood vessels per square centimeter (NBV), and thickness of epidermis (TE). Hair length differed (P<0.001) between slick- and normal-haired animals (4.9 ± 0.12 vs 10.9 ± 0.20, respectively). Differences (P<0.01) in CC (Bayo = 144/67.6% vs Red = 69/32.4%) and HL (slick-haired = 199/93.4% vs normal-haired = 14/6.5%) were found. Distribution of slick- and normal-haired animals differed (P<0.01) between bayo-coated and red-coated (139/62.2% vs 9/4.2%; respectively). Most (P<0.05) red-coated animals belonged to a single family. No differences (P>0.05) were found between slick-haired and normal-haired animals in NHF (637 ± 164 vs 587 ± 144, respectively), NSG (556 ± 134 vs 481 ± 118, respectively), NSBG (408 ± 87 vs 366 ± 77, respectively), NBV (1628 ± 393 vs 1541 ± 346, respectively), and TE (1.24 ± 0.14 vs 1.32 ± 0.12, respectively). However, SGS was greater (P<0.01) in slick-haired than normal-haired animals. In conclusion, Criollo Limonero cattle are predominantly bayo-coated, slick-haired, with a reduced number of hair follicles relative to Zebu cattle, sweat and sebaceous glands in proportion to hair follicle numbers, and with a high blood flow irrigating the skin. There is a sub-group of red-coated animals with yellow or cream skin, thicker epidermis, and with a higher frequency of normal-haired animals. It appears that the slick hair gene has been favored by natural selection in this breed.
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Adaptação Fisiológica/fisiologia , Bovinos/fisiologia , Epiderme/fisiologia , Cabelo/fisiologia , Animais , Biópsia/veterinária , Epiderme/ultraestrutura , Feminino , Cabelo/ultraestrutura , Glândulas Sebáceas/fisiologia , Glândulas Sebáceas/ultraestrutura , Glândulas Sudoríparas/fisiologia , Glândulas Sudoríparas/ultraestruturaRESUMO
Nine non-noble-metal catalysts (NNMCs) from five different laboratories were investigated for the catalysis of O(2) electroreduction in an acidic medium. The catalyst precursors were synthesized by wet impregnation, planetary ball milling, a foaming-agent technique, or a templating method. All catalyst precursors were subjected to one or more heat treatments at 700-1050 degrees C in an inert or reactive atmosphere. These catalysts underwent an identical set of electrochemical characterizations, including rotating-disk-electrode and polymer-electrolyte membrane fuel cell (PEMFC) tests and voltammetry under N(2). Ex situ characterization was comprised of X-ray photoelectron spectroscopy, neutron activation analysis, scanning electron microscopy, and N(2) adsorption and its analysis with an advanced model for carbonaceous powders. In PEMFC, several NNMCs display mass activities of 10-20 A g(-1) at 0.8 V versus a reversible hydrogen electrode, and one shows 80 A g(-1). The latter value corresponds to a volumetric activity of 19 A cm(-3) under reference conditions and represents one-seventh of the target defined by the U.S. Department of Energy for 2010 (130 A cm(-3)). The activity of all NNMCs is mainly governed by the microporous surface area, and active sites seem to be hosted in pore sizes of 5-15 A. The nitrogen and metal (iron or cobalt) seem to be present in sufficient amounts in the NNMCs and do not limit activity. The paper discusses probable directions for synthesizing more active NNMCs. This could be achieved through multiple pyrolysis steps, ball-milling steps, and control of the powder morphology by the addition of foaming agents and/or sulfur.
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Eletroquímica/métodos , Oxigênio/química , Polímeros/química , Catálise , Química/métodos , Eletrodos , Eletrólitos , Concentração de Íons de Hidrogênio , Teste de Materiais , Modelos Estatísticos , Espectroscopia Fotoeletrônica/métodos , Porosidade , Pós/química , Propriedades de SuperfícieRESUMO
Ruthenium oxide materials were evaluated as possible non-carbon-based supports for fuel cell catalysts. The effects of composition and morphology of ruthenium oxide materials on the conductivity and corrosion stability in the gas-diffusion electrode (GDE) configuration were thoroughly investigated. The compositions of the bulk and surface of three ruthenium oxide materials, along with the surface area and surface morphology, were compared. We have found that all tested ruthenium oxide powders exhibited higher corrosion stability compared to carbon. Full conversion of RuO(2).nH(2)O to the RuO(2) phase by postreduction in a hydrogen atmosphere leads to improved conductivity and corrosion stability.
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Chemical structure and catalytic activity of nonplatinum porphyrin-based electrocatalyst for oxygen reduction is characterized by combination of X-ray photoelectron spectroscopy (XPS) and rotating disk electrode. The goal of the study is to show how modifications in the molecular structure affect catalytic characteristics and how to use these structural modifications in a purposeful manner to increase catalytic activity. Initial correlation of structure to electrochemical performance is achieved through the application of principal component analysis (PCA) to curve-fits of high-resolution XPS spectra combined with results of electrochemical measurements. Furthermore, a predictive model that describes this correlation is build using the combination of genetic algorithm (GA) and multiple linear regression (MLR). Based on structure-to-property correlations, two types of active sites responsible for the catalytic activity, i.e., Co associated with pyropolymer and Co particles covered by oxide layer, are determined, and a dual-site for oxygen reduction on cobalt porphyrins is hypothesized, allowing for designing a catalyst structure with optimal performance characteristics.
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Records from ½ Criollo Limonero + ½ Holstein (F1) and backcrosses, ¾ Criollo Limonero + » Holstein (R) handled in a Venezuelan humid tropical forest zone were analyzed to compare their productive and reproductive performance. The analyzed variables were: age at first calving (AFC), interval from calving to conception (ICC), calving interval (CI), services per conception (SC), gestation length (GL), calf birth weight (CBW), lactation length (LL), milk at 90 d (M90), total milk yield (TMY), and milk adjusted to 305 d (M305). No statistical differences (P > 0.05) were found between F1 and R for AFC (3.4 ± 0.1 vs 3.2 ± 0.1 years), SC (1.6 ± 0.1 vs 1.7 ± 0.1), GL (both 280d), CBW (both 34 ± 0.6 kg), M90 (919 ± 99 vs 813 ± 105 kg), TMY (2093 ± 176 vs 1964 ± 176 kg) or for M305 (2424 ± 146 vs 2430 ± 151kg), respectively. However, the F1 cows had ICC (258 ± 18 vs 173 ± 22 d; P < 0.004) and CI (577 ± 21 vs 474 ± 25 d; P < 0.001) longer than R, respectively. Year of birth affected (P < 0.05) to AFC, (P < 0.03) to ICC, and (P < 0.01) to CI, M90, TMY, and M305. Environmental effects were found for GL, M90, TMY, M305, and LL. Although no differences between genotypes were found for milk yield, R cows had better reproductive performance than the F1 cows.
Con el objetivo de comparar el comportamiento productivo y reproductivo, se analizaron los registros de vacas ½ Criollo Limonero + ½ Holstein (F1) y retrocruces ¾ Criollo Limonero + » Holstein (R) manejadas en una zona de bosque húmedo tropical venezolana. Se analizaron las variables edad al primer parto (AFC), intervalo parto-concepción (ICC), intervalo entre partos (CI), servicios por concepción (SC), duración de la gestación (GL), peso al nacer de los becerros (CBW), longitud de lactancia (LL), producción de leche total (TMY), a los 90 días (M90) y ajustada a 305 días (M305). No se hallaron diferencias significativas (P > 0,05) entre F1 y R para AFC (3,4 ± 0,1 vs 3,2 ± 0,1 años), SC (1,6 ± 0,1 vs 1,7 ± 0,1), GL (ambos 280d), CBW (ambos 34 ± 0,6 kg), M90 (919 ± 99 vs 813 ± 105 kg), TMY (2093 ± 176 vs 1964 ± 176 kg) ni M305 (2424 ± 146 vs 2430 ± 151kg), respectivamente. No obstante, las F1 tuvieron ICC (258 ± 18 vs 173 ± 22 d; P < 0,004) e CI (577 ± 21 vs 474 ± 25 d; P < 0,001) más prolongados que las R, respectivamente. El año de nacimiento afectó (P < 0,05) a AFC, (P < 0,03) ICC, y (P < 0,01) a CI, M90, TMY, y M305. Se hallaron efectos climáticos sobre GL, M90, TMY, M305, y LL. Aunque sin diferencias en producción de leche, las R tuvieron mejor desempeño reproductivo.
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Electrodeposition of adhesive metal films on aluminum is traditionally preceded by the zincate process, which activates the aluminum surface. This paper presents an alternative approach for activation of aluminum by using films containing 99.5% aluminum and 0.5% copper. Aluminum/copper films are made amenable for subsequent electrodeposition by anodization followed by chemical etching of aluminum oxide. The electrodeposition of gold is monitored with electrochemical impedance spectroscopy (EIS). Analysis of EIS data suggests that electrodeposition of gold increases the interfacial capacitance from values typical for electrodes with thin oxide layers to values typical for metal electrodes. Scanning electron microscopy examination of aluminum/copper films following gold electrodeposition shows the presence of gold particles with densities of 10(5)-10(7) particles cm(-2). The relative standard deviation of mean particle diameters is approximately 25%. Evaluation of the micrographs suggests that the electrodeposition occurs by instantaneous nucleation followed by growth of three-dimensional semispherical particles. The gold particles, which are electrically connected to the conductive aluminum/copper film, support a reversible faradaic process for a soluble redox couple. The deposited gold particles are suitable for subsequent metallization of aluminum and fabrication of particle-type films with interesting catalytic, electrical, and optical properties.