Chemotherapy Wait Times in a Network of Pediatric Oncology Clinics.

Patient satisfaction with medical care delivery is an important aspect of value-based health care. Providers strive to provide optimal patient satisfaction. Among a network of ambulatory pediatric oncology affiliate clinics, we conducted patient satisfaction surveys and found that the lowest scores were related to delays in the administration of chemotherapy. To address this shortcoming, we used continuous improvement methodologies to reduce the delay in chemotherapy administration in 3 affiliate clinics. To evaluate the efficacy of the quality improvement interventions implemented at each affiliate clinic, we measured the time from patient arrival to the start of chemotherapy administration over a 2-week period before and after the interventions. Wait times for chemotherapy administration were reduced in each clinic by 7% to 15%, exceeding the preestablished goal of a 5% reduction without affecting patient safety. Patient satisfaction for chemotherapy wait times was also marginally increased. In conclusion, implementation of quality improvement interventions across a clinical network can improve specific aspects of patient satisfaction, thereby improving the overall patient experience.

Timing of the loss of Pten protein determines disease severity in a mouse model of myeloid malignancy.

Juvenile myelomonocytic leukemia (JMML) is an aggressive pediatric mixed myelodysplastic/myeloproliferative neoplasm (MDS/MPN). JMML leukemogenesis is linked to a hyperactivated RAS pathway, with driver mutations in the KRAS, NRAS, NF1, PTPN11, or CBL genes. Previous murine models demonstrated how those genes contributed to the selective hypersensitivity of JMML cells to granulocyte macrophage-colony-stimulating factor (GM-CSF), a unifying characteristic in the disease. However, it is unclear what causes the early death in children with JMML, because transformation to acute leukemia is rare. Here, we demonstrate that loss of Pten (phosphatase and tensin homolog) protein at postnatal day 8 in mice harboring Nf1 haploinsufficiency results in an aggressive MPN with death at a murine prepubertal age of 20 to 35 days (equivalent to an early juvenile age in JMML patients). The death in the mice was due to organ infiltration with monocytes/macrophages. There were elevated activities of protein kinase B (Akt) and mitogen-activated protein kinase (MAPK) in cells at physiological concentrations of GM-CSF. These were more pronounced in mice with Nf1 haploinsufficiency than in littermates with wild-type Nf1,but this model is insufficient to cause cells to be GM-CSF hypersensitive. This new model represents a murine MPN model with features of a pediatric unclassifiable mixed MDS/MPN and mimics many clinical manifestations of JMML in terms of age of onset, aggressiveness, and organ infiltration with monocytes/macrophages. Our data suggest that the timing of the loss of PTEN protein plays a critical role in determining the disease severity in myeloid malignancies. This model may be useful for studying the pathogenesis of pediatric diseases with alterations in the Ras pathway.

Polyplexes System to Enhance the LL-37 Antimicrobial Peptide Expression in Human Skin Cells.

Inefficient autologous tissue recovery in diverse skin injuries increases the susceptibility of patients to infections caused by multiresistant microorganisms, resulting in a high mortality rate. Nonviral transfection is an attractive alternative for these patients, where genetically modified cells incorporated into skin substitutes could release additional antimicrobial agents into the native skin. In this work, we have modulated the conditions of using a nonviral system for transfection of primary human keratinocytes and fibroblasts, consisting of a polymer/plasmid DNA (pDNA) complex called polyplex and its effects on the expression of LL-37 antimicrobial peptide. Linear and branched polyethylenimine (PEI) polymers in different weight concentrations were varied for evaluating the formation and colloidal characteristics of the polyplexes. The PEI/pDNA polyplexes with 19 nitrogen/phosphate ratio are nanometric particles (400 and 250 nm with linear and branched PEI, respectively) exhibiting positive surface (+30 ± 2 mV). Both kinds of polyplexes allowed the expression of a reporter gene and increased the human cathelicidin antimicrobial peptide gene expression in transfected keratinocytes and fibroblasts; however, greater cytotoxicity was observed when polyplexes formed with branched PEI were used. Moreover, cell culture supernatants from transfected cells with linear PEI/pDNA polyplexes showed enhanced antimicrobial activity (decrease of bacterial growth in 95.8%) against a Staphylococcus aureus strain in vitro. The study of the PEI/pDNA polyplexes formation allowed us to develop an improved transfection strategy of skin cells, promoting the production of LL-37 antimicrobial peptide. In the future, this strategy could be used for the construction of skin substitutes to prevent, reduce, or eliminate bacterial infections. Impact statement The results of this study contribute to the understanding of the polyplexes system in the genetic modification of skin cells and its effects on the expression of the LL-37 antimicrobial peptide. In the future, three-dimensional skin substitutes built with these cells could be an efficient way to decrease bacterial growth and prevent the infections in skin wounds.

Sustained fetal hematopoiesis causes juvenile death from leukemia: evidence from a dual-age-specific mouse model.

It is not clear whether disrupted age-specific hematopoiesis contributes to the complex manifestations in leukemia patients who carry identical mutations, particularly in pediatric and adult patients with similar clinical characteristics. By studying a dual-age-specific mouse model, we demonstrate that (1) loss of Pten during the fetal-to-adult hematopoiesis switch (hematopoiesis switch) causes sustained fetal hematopoiesis, resulting in death in juvenile leukemia; (2) myeloid-biased hematopoiesis in juvenile mice is associated with the sustained fetal properties of hematopoietic stem cells (HSCs); (3) the age specificity of juvenile myelomonocytic leukemia depends on the copy number of Pten and Nf1; (4) single-allelic Pten deletion during the hematopoiesis switch causes constitutive activation of MAPK in juvenile mice with Nf1 loss of heterozygosity (LOH); and (5) Nf1 LOH causes monocytosis in juvenile mice with Pten haploinsufficiency but does not cause lethality until adulthood. Our data suggest that 1 copy of Pten is sufficient to maintain an intact negative-feedback loop of the Akt pathway and HSC function in reconstitution, despite MAPK being constitutively activated in juvenile Pten+/ΔNf1LOH mice. However, 2 copies of Pten are required to maintain the integrity of the MAPK pathway in juvenile mice with Nf1 haploinsufficiency. Our data indicate that previous investigations of Pten function in wild-type mice may not reflect the impact of Pten loss in mice with Nf1 mutations or other genetic defects. We provide a proof of concept that disassociated age-specific hematopoiesis contributes to leukemogenesis and pediatric demise.

Polyplex System Versus Nucleofection for Human Skin Cell Transfection and Effect of Internal Ribosome Entry Site Sequence.

Nonviral transfection has important implications on gene therapy because of its safety. In particular, polyfection and nucleofection are two widely used systems for nonviral gene delivery. Their potential depends on the transfection efficiency achieved, which is influenced in turn by the type of cells transfected and by the plasmid that carries the gene of interest. The efficiency of transfection by polyfection or nucleofection in human fibroblasts and keratinocytes was evaluated in this study. Transfections were performed with plasmids containing a gene of interest (human cathelicidin antimicrobial peptide) and two reporter genes (red or green fluorescent protein) that included or not an internal ribosome entry site (IRES). The efficiency was measured by flow cytometry in terms of percentage of cells expressing the reporter gene; viability of transfected cells was also evaluated. It was found that nucleofection was more efficient than polyplexes for transfecting fibroblasts, while no significant differences were found between both systems of transfection when applied to keratinocytes. Regarding the viability of fibroblasts after transfection, values were high in both systems. In contrast, keratinocytes were more sensitive to nucleofection. It was also noted that both types of cells decreased reporter gene expression when IRES sequence was located upstream of the reporter gene, suggesting a negative effect on the expression of this gene. These results confirm that the transfection efficiency depends on the type of cells and the system used.

Calidad de vida relacionada con la salud en usuarios de un programa de actividad física / Health-related quality of life in users of a physical activity program

Introducción: la calidad de vida relacionada con la salud (CVRS) permite evaluar el estado de salud de las personas y diseñar, implementar y evaluar programas de salud. Objetivo: determinar la percepción de la CVRS en usuarios de un programa de actividad física (AF). Metodología: estudio transversal en 177 sujetos pertenecientes a un programa de actividad física. Se aplicó el cuestionario SF-36v1.2 para evaluar la CVRS; se evaluó el consumo máximo de oxígeno (VO2máx) por medio la prueba de 2.000 metros y se determinó la prevalencia de algunos factores de riesgo cardiovascular a partir de las historias clínicas. Resultados: el puntaje promedio de CVRS más alto fue en el funcionamiento físico (FF) 90,5 (DE: 10,8) y más bajo en dolor corporal (DC) 78,1 (DE: 22,4) y vitalidad (VT) 78,1 (DE: 15,5). En las personas fumadoras, hipertensas, diabéticas, obesas y con niveles bajos de actividad fisica la mayoría de los puntajes de CVRS fueron más bajos (diferencias clínica y estadísticamente significativas). El VO2máx mostró correlación con los dominios funcionamiento físico (FF) (rho = 0,371; p = 0,0001), desempeño físico (DF) (rho = 0,177; p = 0,018) y dolor corporal (DC) (rho = 0,207; p = 0,006). Conclusión: las personas estudiadas tienen una percepción buena de la CVRS; sin embargo, en quienes reportaron tabaquismo, hipertensión arterial, diabetes mellitus, obesidad, dislipidemias y baja potencia aeróbica se presentó una menor percepción de la CVRS; las personas con obesidad mostraron mejores puntajes en los dominios del componente mental y aquellos con bajo nivel de AF mostraron puntajes bajos en dicho componente.

Introduction: Health related quality of life (HRQL) allows to assess people health status, and to design, implement and evaluate health programs. Objective: To determine the perception of HRQL in users of a physical activity (PA) program. Methodology: Cross-sectional study in 177 subjects belonging to a physical activity program. SF-36v1.2 questionnaire was used to assess HRQL; maximal oxygen consumption (VO2max) was evaluated by the 2.000 meters test and prevalence of some cardiovascular risk factors was determined from medical records. Results: The higher average score for HRQL was in physical function (PF) 90,5 (SD: 10.8), compared with the lowest scores of body pain (BP) 78,1 (SD: 22,4) and vitality (VT) 78,1 (SD: 15,5). In smokers, hypertensive, diabetics, obese and people with low levels of physical activity most HRQL scores were lower (clinically and statistically significant differences). VO2max correlated with PF subscales (rho = 0.371; p = 0.0001), physical performance (rho = 0.177; p = 0.018) and BP (rho = 0.207; p = 0.006). Conclusion: The studied individuals have a good perception of HRQL; nevertheless, those who reported smoking, hypertension, diabetes, obesity, dyslipidemia and low aerobic power, had a reduced perception of HRQL; obese people showed improved scores in mental component domains and those with low levels of PA showed low scores in that component.