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1.
Clin Trials ; 21(2): 189-198, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-37877369

RESUMEN

BACKGROUND/AIMS: We developed an observer disfigurement severity scale for neurofibroma-related plexiform neurofibromas to assess change in plexiform neurofibroma-related disfigurement and evaluated its feasibility, reliability, and validity. METHODS: Twenty-eight raters, divided into four cohorts based on neurofibromatosis type 1 familiarity and clinical experience, were shown photographs of children in a clinical trial (NCT01362803) at baseline and 1 year on selumetinib treatment for plexiform neurofibromas (n = 20) and of untreated participants with plexiform neurofibromas (n = 4). Raters, blinded to treatment and timepoint, completed the 0-10 disfigurement severity score for plexiform neurofibroma on each image (0 = not at all disfigured, 10 = very disfigured). Raters evaluated the ease of completing the scale, and a subset repeated the procedure to assess intra-rater reliability. RESULTS: Mean baseline disfigurement severity score for plexiform neurofibroma ratings were similar for the selumetinib group (6.23) and controls (6.38). Mean paired differences between pre- and on-treatment ratings was -1.01 (less disfigurement) in the selumetinib group and 0.09 in the control (p = 0.005). For the disfigurement severity score for plexiform neurofibroma ratings, there was moderate-to-substantial agreement within rater cohorts (weighted kappa range = 0.46-0.66) and agreement between scores of the same raters at repeat sessions (p > 0.05). In the selumetinib group, change in disfigurement severity score for plexiform neurofibroma ratings was moderately correlated with change in plexiform neurofibroma volume with treatment (r = 0.60). CONCLUSION: This study demonstrates that our observer-rated disfigurement severity score for plexiform neurofibroma was feasible, reliable, and documented improvement in disfigurement in participants with plexiform neurofibroma shrinkage. Prospective studies in larger samples are needed to validate this scale further.


Asunto(s)
Neurofibroma Plexiforme , Neurofibromatosis 1 , Niño , Humanos , Neurofibroma Plexiforme/tratamiento farmacológico , Neurofibromatosis 1/tratamiento farmacológico , Estudios Prospectivos , Reproducibilidad de los Resultados
2.
N Engl J Med ; 382(15): 1430-1442, 2020 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-32187457

RESUMEN

BACKGROUND: No approved therapies exist for inoperable plexiform neurofibromas in patients with neurofibromatosis type 1. METHODS: We conducted an open-label, phase 2 trial of selumetinib to determine the objective response rate among patients with plexiform neurofibromas and to assess clinical benefit. Children with neurofibromatosis type 1 and symptomatic inoperable plexiform neurofibromas received oral selumetinib twice daily at a dose of 25 mg per square meter of body-surface area on a continuous dosing schedule (28-day cycles). Volumetric magnetic resonance imaging and clinical outcome assessments (pain, quality of life, disfigurement, and function) were performed at least every four cycles. Children rated tumor pain intensity on a scale from 0 (no pain) to 10 (worst pain imaginable). RESULTS: A total of 50 children (median age, 10.2 years; range, 3.5 to 17.4) were enrolled from August 2015 through August 2016. The most frequent neurofibroma-related symptoms were disfigurement (44 patients), motor dysfunction (33), and pain (26). A total of 35 patients (70%) had a confirmed partial response as of March 29, 2019, and 28 of these patients had a durable response (lasting ≥1 year). After 1 year of treatment, the mean decrease in child-reported tumor pain-intensity scores was 2 points, considered a clinically meaningful improvement. In addition, clinically meaningful improvements were seen in child-reported and parent-reported interference of pain in daily functioning (38% and 50%, respectively) and overall health-related quality of life (48% and 58%, respectively) as well as in functional outcomes of strength (56% of patients) and range of motion (38% of patients). Five patients discontinued treatment because of toxic effects possibly related to selumetinib, and 6 patients had disease progression. The most frequent toxic effects were nausea, vomiting, or diarrhea; an asymptomatic increase in the creatine phosphokinase level; acneiform rash; and paronychia. CONCLUSIONS: In this phase 2 trial, most children with neurofibromatosis type 1 and inoperable plexiform neurofibromas had durable tumor shrinkage and clinical benefit from selumetinib. (Funded by the Intramural Research Program of the National Institutes of Health and others; ClinicalTrials.gov number, NCT01362803.).


Asunto(s)
Bencimidazoles/uso terapéutico , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Neurofibroma Plexiforme/tratamiento farmacológico , Neurofibromatosis 1/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Adolescente , Bencimidazoles/efectos adversos , Niño , Preescolar , Femenino , Humanos , Masculino , Náusea/inducido químicamente , Neurofibroma Plexiforme/complicaciones , Neurofibroma Plexiforme/patología , Neurofibromatosis 1/complicaciones , Neurofibromatosis 1/patología , Dolor/etiología , Medición de Resultados Informados por el Paciente , Supervivencia sin Progresión , Inhibidores de Proteínas Quinasas/efectos adversos , Carga Tumoral/efectos de los fármacos
3.
PLoS Pathog ; 17(6): e1009475, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34107000

RESUMEN

Tsetse flies are vectors of parasitic African trypanosomes, the etiological agents of human and animal African trypanosomoses. Current disease control methods include fly-repelling pesticides, fly trapping, and chemotherapeutic treatment of infected people and animals. Inhibiting tsetse's ability to transmit trypanosomes by strengthening the fly's natural barriers can serve as an alternative approach to reduce disease. The peritrophic matrix (PM) is a chitinous and proteinaceous barrier that lines the insect midgut and serves as a protective barrier that inhibits infection with pathogens. African trypanosomes must cross tsetse's PM in order to establish an infection in the fly, and PM structural integrity negatively correlates with trypanosome infection outcomes. Bloodstream form trypanosomes shed variant surface glycoproteins (VSG) into tsetse's gut lumen early during the infection establishment, and free VSG molecules are internalized by the fly's PM-producing cardia. This process results in a reduction in the expression of a tsetse microRNA (miR275) and a sequential molecular cascade that compromises PM integrity. miRNAs are small non-coding RNAs that are critical in regulating many physiological processes. In the present study, we investigated the role(s) of tsetse miR275 by developing a paratransgenic expression system that employs tsetse's facultative bacterial endosymbiont, Sodalis glossinidius, to express tandem antagomir-275 repeats (or miR275 sponges). This system induces a constitutive, 40% reduction in miR275 transcript abundance in the fly's midgut and results in obstructed blood digestion (gut weights increased by 52%), a significant increase (p-value < 0.0001) in fly survival following infection with an entomopathogenic bacteria, and a 78% increase in trypanosome infection prevalence. RNA sequencing of cardia and midgut tissues from paratransgenic tsetse confirmed that miR275 regulates processes related to the expression of PM-associated proteins and digestive enzymes as well as genes that encode abundant secretory proteins. Our study demonstrates that paratransgenesis can be employed to study microRNA regulated pathways in arthropods that house symbiotic bacteria.


Asunto(s)
Homeostasis/fisiología , Intestinos/fisiología , MicroARNs/genética , Tripanosomiasis Africana/parasitología , Moscas Tse-Tse/genética , Moscas Tse-Tse/parasitología , Animales , Animales Modificados Genéticamente , Microbioma Gastrointestinal/fisiología , Genes de Insecto , Insectos Vectores/genética , Insectos Vectores/parasitología , Trypanosoma
4.
PLoS Pathog ; 17(9): e1009539, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34529715

RESUMEN

Tsetse flies (Glossina spp.) house a population-dependent assortment of microorganisms that can include pathogenic African trypanosomes and maternally transmitted endosymbiotic bacteria, the latter of which mediate numerous aspects of their host's metabolic, reproductive, and immune physiologies. One of these endosymbionts, Spiroplasma, was recently discovered to reside within multiple tissues of field captured and laboratory colonized tsetse flies grouped in the Palpalis subgenera. In various arthropods, Spiroplasma induces reproductive abnormalities and pathogen protective phenotypes. In tsetse, Spiroplasma infections also induce a protective phenotype by enhancing the fly's resistance to infection with trypanosomes. However, the potential impact of Spiroplasma on tsetse's viviparous reproductive physiology remains unknown. Herein we employed high-throughput RNA sequencing and laboratory-based functional assays to better characterize the association between Spiroplasma and the metabolic and reproductive physiologies of G. fuscipes fuscipes (Gff), a prominent vector of human disease. Using field-captured Gff, we discovered that Spiroplasma infection induces changes of sex-biased gene expression in reproductive tissues that may be critical for tsetse's reproductive fitness. Using a Gff lab line composed of individuals heterogeneously infected with Spiroplasma, we observed that the bacterium and tsetse host compete for finite nutrients, which negatively impact female fecundity by increasing the length of intrauterine larval development. Additionally, we found that when males are infected with Spiroplasma, the motility of their sperm is compromised following transfer to the female spermatheca. As such, Spiroplasma infections appear to adversely impact male reproductive fitness by decreasing the competitiveness of their sperm. Finally, we determined that the bacterium is maternally transmitted to intrauterine larva at a high frequency, while paternal transmission was also noted in a small number of matings. Taken together, our findings indicate that Spiroplasma exerts a negative impact on tsetse fecundity, an outcome that could be exploited for reducing tsetse population size and thus disease transmission.


Asunto(s)
Insectos Vectores/microbiología , Insectos Vectores/fisiología , Spiroplasma , Simbiosis/fisiología , Moscas Tse-Tse/microbiología , Moscas Tse-Tse/fisiología , Animales , Femenino , Masculino
5.
Proc Natl Acad Sci U S A ; 117(5): 2613-2621, 2020 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-31964820

RESUMEN

Tsetse-transmitted African trypanosomes must develop into mammalian-infectious metacyclic cells in the fly's salivary glands (SGs) before transmission to a new host. The molecular mechanisms that underlie this developmental process, known as metacyclogenesis, are poorly understood. Blocking the few metacyclic parasites deposited in saliva from further development in the mammal could prevent disease. To obtain an in-depth perspective of metacyclogenesis, we performed single-cell RNA sequencing (scRNA-seq) from a pool of 2,045 parasites collected from infected tsetse SGs. Our data revealed three major cell clusters that represent the epimastigote, and pre- and mature metacyclic trypanosome developmental stages. Individual cell level data also confirm that the metacyclic pool is diverse, and that each parasite expresses only one of the unique metacyclic variant surface glycoprotein (mVSG) coat protein transcripts identified. Further clustering of cells revealed a dynamic transcriptomic and metabolic landscape reflective of a developmental program leading to infectious metacyclic forms preadapted to survive in the mammalian host environment. We describe the expression profile of proteins that regulate gene expression and that potentially play a role in metacyclogenesis. We also report on a family of nonvariant surface proteins (Fam10) and demonstrate surface localization of one member (named SGM1.7) on mature metacyclic parasites. Vaccination of mice with recombinant SGM1.7 reduced parasitemia early in the infection. Future studies are warranted to investigate Fam10 family proteins as potential trypanosome transmission blocking vaccine antigens. Our experimental approach is translationally relevant for developing strategies to prevent other insect saliva-transmitted parasites from infecting and causing disease in mammalian hosts.


Asunto(s)
Insectos Vectores/parasitología , Proteínas Protozoarias/genética , Trypanosoma brucei brucei/crecimiento & desarrollo , Trypanosoma brucei brucei/genética , Moscas Tse-Tse/parasitología , Animales , Femenino , Humanos , Estadios del Ciclo de Vida , Ratones , Ratones Endogámicos BALB C , Proteínas Protozoarias/inmunología , ARN Protozoario/genética , Glándulas Salivales/parasitología , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Transcriptoma , Trypanosoma brucei brucei/inmunología , Tripanosomiasis Africana/inmunología , Tripanosomiasis Africana/parasitología
6.
Microbiology (Reading) ; 168(9)2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36129743

RESUMEN

Wigglesworthia glossinidia is an obligate, maternally transmitted endosymbiont of tsetse flies. The ancient association between these two organisms accounts for many of their unique physiological adaptations. Similar to other obligate mutualists, Wigglesworthia's genome is dramatically reduced in size, yet it has retained the capacity to produce many B-vitamins that are found at inadequate quantities in the fly's vertebrate blood-specific diet. These Wigglesworthia-derived B-vitamins play essential nutritional roles to maintain tsetse's physiological homeostasis as well as that of other members of the fly's microbiota. In addition to its nutritional role, Wigglesworthia contributes towards the development of tsetse's immune system during the larval period. Tsetse produce amidases that degrade symbiotic peptidoglycans and prevent activation of antimicrobial responses that can damage Wigglesworthia. These amidases in turn exhibit antiparasitic activity and decrease tsetse's ability to be colonized with parasitic trypanosomes, which reduce host fitness. Thus, the Wigglesworthia symbiosis represents a fine-tuned association in which both partners actively contribute towards achieving optimal fitness outcomes.


Asunto(s)
Moscas Tse-Tse , Wigglesworthia , Amidohidrolasas/metabolismo , Animales , Antiparasitarios/metabolismo , Simbiosis , Moscas Tse-Tse/parasitología , Moscas Tse-Tse/fisiología , Vitaminas/metabolismo , Wigglesworthia/metabolismo
7.
PLoS Genet ; 15(3): e1008005, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30875383

RESUMEN

Dipteran or "true" flies occupy nearly every terrestrial habitat, and have evolved to feed upon a wide variety of sources including fruit, pollen, decomposing animal matter, and even vertebrate blood. Here we analyze the molecular, genetic and cellular basis of odor response in the tsetse fly Glossina morsitans, which feeds on the blood of humans and their livestock, and is a vector of deadly trypanosomes. The G. morsitans antenna contains specialized subtypes of sensilla, some of which line a sensory pit not found in the fruit fly Drosophila. We characterize distinct patterns of G. morsitans Odor receptor (GmmOr) gene expression in the antenna. We devise a new version of the "empty neuron" heterologous expression system, and use it to functionally express several GmmOrs in a mutant olfactory receptor neuron (ORN) of Drosophila. GmmOr35 responds to 1-hexen-3-ol, an odorant found in human emanations, and also alpha-pinene, a compound produced by malarial parasites. Another receptor, GmmOr9, which is expressed in the sensory pit, responds to acetone, 2-butanone and 2-propanol. We confirm by electrophysiological recording that neurons of the sensory pit respond to these odorants. Acetone and 2-butanone are strong attractants long used in the field to trap tsetse. We find that 2-propanol is also an attractant for both G. morsitans and the related species G. fuscipes, a major vector of African sleeping sickness. The results identify 2-propanol as a candidate for an environmentally friendly and practical tsetse attractant. Taken together, this work characterizes the olfactory system of a highly distinct kind of fly, and it provides an approach to identifying new agents for controlling the fly and the devastating diseases that it carries.


Asunto(s)
Receptores Odorantes/genética , Atractivos Sexuales/genética , Olfato/genética , Tripanosomiasis Africana/genética , 2-Propanol/química , Animales , Drosophila melanogaster/genética , Drosophila melanogaster/parasitología , Humanos , Aceites/química , Neuronas Receptoras Olfatorias/metabolismo , Neuronas Receptoras Olfatorias/parasitología , Atractivos Sexuales/química , Trypanosoma/genética , Trypanosoma/patogenicidad , Tripanosomiasis Africana/parasitología , Moscas Tse-Tse/genética , Moscas Tse-Tse/patogenicidad
8.
PLoS Pathog ; 15(2): e1007470, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30817773

RESUMEN

Tsetse flies (Glossina spp.) vector pathogenic trypanosomes (Trypanosoma spp.) in sub-Saharan Africa. These parasites cause human and animal African trypanosomiases, which are debilitating diseases that inflict an enormous socio-economic burden on inhabitants of endemic regions. Current disease control strategies rely primarily on treating infected animals and reducing tsetse population densities. However, relevant programs are costly, labor intensive and difficult to sustain. As such, novel strategies aimed at reducing tsetse vector competence require development. Herein we investigated whether Kosakonia cowanii Zambiae (Kco_Z), which confers Anopheles gambiae with resistance to Plasmodium, is able to colonize tsetse and induce a trypanosome refractory phenotype in the fly. Kco_Z established stable infections in tsetse's gut and exhibited no adverse effect on the fly's survival. Flies with established Kco_Z infections in their gut were significantly more refractory to infection with two distinct trypanosome species (T. congolense, 6% infection; T. brucei, 32% infection) than were age-matched flies that did not house the exogenous bacterium (T. congolense, 36% infected; T. brucei, 70% infected). Additionally, 52% of Kco_Z colonized tsetse survived infection with entomopathogenic Serratia marcescens, compared with only 9% of their wild-type counterparts. These parasite and pathogen refractory phenotypes result from the fact that Kco_Z acidifies tsetse's midgut environment, which inhibits trypanosome and Serratia growth and thus infection establishment. Finally, we determined that Kco_Z infection does not impact the fecundity of male or female tsetse, nor the ability of male flies to compete with their wild-type counterparts for mates. We propose that Kco_Z could be used as one component of an integrated strategy aimed at reducing the ability of tsetse to transmit pathogenic trypanosomes.


Asunto(s)
Trypanosoma brucei brucei/patogenicidad , Trypanosoma congolense/patogenicidad , Tripanosomiasis Africana/prevención & control , Moscas Tse-Tse/microbiología , Moscas Tse-Tse/parasitología , Adulto , África del Sur del Sahara , Animales , Anopheles/microbiología , Enterobacteriaceae , Femenino , Humanos , Masculino , Mosquitos Vectores/microbiología , Mosquitos Vectores/parasitología , Simbiosis , Tripanosomiasis Africana/metabolismo , Tripanosomiasis Africana/microbiología , Tripanosomiasis Africana/parasitología
10.
Pediatr Blood Cancer ; 68(5): e28920, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33644927

RESUMEN

INTRODUCTION: Diffuse liver lesions in an infant have a differential diagnosis including infantile hemangioma (IH), which is common in the first year of life, and neuroblastoma (NBL) which presents at a median age of 18 months. RESULTS: We describe the case of a 4-month-old girl with a known superficial/deep IH who presented with new axillary nodules and hepatosplenomegaly, initially suspected to reflect IH but later determined to be widely metastatic NBL. CONCLUSION: Hepatic IH and metastatic NBL can present similarly. Clinicians must maintain a broad differential when evaluating new findings in a patient with previously diagnosed IH.


Asunto(s)
Hemangioma/patología , Neoplasias Hepáticas/patología , Neoplasias Primarias Múltiples/diagnóstico , Neuroblastoma/patología , Neoplasias Cutáneas/patología , Diagnóstico Diferencial , Femenino , Humanos , Lactante , Neoplasias Hepáticas/diagnóstico , Neoplasias Primarias Múltiples/patología , Neuroblastoma/diagnóstico
11.
Pediatr Blood Cancer ; 68(3): e28852, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33381917

RESUMEN

Autologous hematopoietic cell transplant (aHCT) has a significant survival advantage in patients with high-risk (HR) neuroblastoma. Transplant-associated thrombotic microangiopathy (TA-TMA) is a serious complication and may result in chronic renal disease leading to delay in subsequent posttransplant therapy and limitations of treatment options. Dinutuximab represents an important therapeutic advance in the treatment of pediatric HR neuroblastoma, but historically has not been administered in patients with GFR < 60 mL/m2 /min. Here, we present the safe outcome of dinutuximab administration while on renal replacement therapy in two cases of HR neuroblastoma with end-stage renal disease secondary to TA-TMA.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Fallo Renal Crónico/tratamiento farmacológico , Neuroblastoma/terapia , Diálisis Renal , Niño , Preescolar , Humanos , Fallo Renal Crónico/etiología , Fallo Renal Crónico/patología , Masculino , Neuroblastoma/patología , Pronóstico
12.
Pediatr Blood Cancer ; 68(10): e29117, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34028986

RESUMEN

INTRODUCTION: 131 I-meta-iodobenzylguanidine (131 I-MIBG) is effective in relapsed neuroblastoma. The Children's Oncology Group (COG) conducted a pilot study (NCT01175356) to assess tolerability and feasibility of induction chemotherapy followed by 131 I- MIBG therapy and myeloablative busulfan/melphalan (Bu/Mel) in patients with newly diagnosed high-risk neuroblastoma. METHODS: Patients with MIBG-avid high-risk neuroblastoma were eligible. After the first two patients to receive protocol therapy developed severe sinusoidal obstruction syndrome (SOS), the trial was re-designed to include an 131 I-MIBG dose escalation (12, 15, and 18 mCi/kg), with a required 10-week gap before Bu/Mel administration. Patients who completed induction chemotherapy were evaluable for assessment of 131 I-MIBG feasibility; those who completed 131 I-MIBG therapy were evaluable for assessment of 131 I-MIBG + Bu/Mel feasibility. RESULTS: Fifty-nine of 68 patients (86.8%) who completed induction chemotherapy received 131 I-MIBG. Thirty-seven of 45 patients (82.2%) evaluable for 131 I-MIBG + Bu/Mel received this combination. Among those who received 131 I-MIBG after revision of the study design, one patient per dose level developed severe SOS. Rates of moderate to severe SOS at 12, 15, and 18 mCi/kg were 33.3%, 23.5%, and 25.0%, respectively. There was one toxic death. The 131 I-MIBG and 131 I-MIBG+Bu/Mel feasibility rates at the 15 mCi/kg dose level designated for further study were 96.7% (95% CI: 83.3%-99.4%) and 81.0% (95% CI: 60.0%-92.3%). CONCLUSION: This pilot trial demonstrated feasibility and tolerability of administering 131 I-MIBG followed by myeloablative therapy with Bu/Mel to newly diagnosed children with high-risk neuroblastoma in a cooperative group setting, laying the groundwork for a cooperative randomized trial (NCT03126916) testing the addition of 131 I-MIBG during induction therapy.


Asunto(s)
3-Yodobencilguanidina , Neuroblastoma , 3-Yodobencilguanidina/efectos adversos , 3-Yodobencilguanidina/uso terapéutico , Busulfano/uso terapéutico , Estudios de Factibilidad , Humanos , Radioisótopos de Yodo , Recurrencia Local de Neoplasia , Neuroblastoma/radioterapia , Proyectos Piloto
13.
Pediatr Radiol ; 51(8): 1400-1405, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33629142

RESUMEN

BACKGROUND: 18F-2-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) shows tumor activity in most neuroblastomas, but the role of 18F-FDG PET/CT in neuroblastoma remains to be defined. OBJECTIVE: This study explored the prognostic significance of 18F-FDG PET in newly diagnosed neuroblastic tumors. MATERIALS AND METHODS: This retrospective study reviewed all 18F-FDG PET/CT examinations performed for a new diagnosis of suspected neuroblastoma. MYCN amplification status, tumor recurrence and survival were abstracted from the medical record. Primary tumors were manually segmented to measure maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), tumor volume and total lesion glycolysis. Univariate and multivariable analyses using Cox proportional hazards regression testing assessed the predictive performance of PET indices for event-free survival and overall survival with thresholds determined using receiver operating characteristic curve analysis. RESULTS: Fifty-five children were included, with a median age of 2.9 years (interquartile range [IQR] 1.8-3.0 years). SUVmax, tumor volume and total lesion glycolysis were higher in MYCN-amplified tumors (P=0.012, P<0.0001, P<0.0001, respectively) and in higher International Neuroblastoma Risk Group (INRG) stages (P=0.0008, P=0.0017, P=0.0017, respectively). After adjusting for age, tumor SUVmax (P=0.028) and SUVmean (P=0.045) were associated with overall survival. An SUVmax threshold of 4.77 (P=0.028) best predicted overall survival, with median overall survival of 2,604 days (SUVmax>4.77) vs. >2,957 days (SUVmax≤4.77). No PET parameters were independently significantly associated with overall survival or event-free survival after controlling for MYCN status, stage or treatment risk stratification. CONCLUSION: Tumor metabolic activity is higher in higher-stage MYCN-amplified neuroblastic tumors. Higher SUVmax and SUVmean were associated with worse overall survival but were not independent of other prognostic markers.


Asunto(s)
Neuroblastoma , Tomografía Computarizada por Tomografía de Emisión de Positrones , Niño , Preescolar , Fluorodesoxiglucosa F18 , Humanos , Lactante , Recurrencia Local de Neoplasia , Neuroblastoma/diagnóstico por imagen , Tomografía de Emisión de Positrones , Pronóstico , Radiofármacos , Estudios Retrospectivos
14.
Pediatr Emerg Care ; 37(8): e474-e478, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32398595

RESUMEN

OBJECTIVES: Pediatric cervical spine injuries are rare but potentially life threatening. Although published guidelines for assessment of such injuries exist, there is less uniformity in its implementation in out-of-hospital settings. Our purpose was to assess the knowledge and practice patterns for pediatric cervical spine immobilization among prehospital emergency medical services (EMS) providers in Arizona. METHODS: A cross-sectional web-based survey was conducted (October-December 2018), using an electronic mailing list of certified EMS providers (ground and air) in Arizona. A 20-question structured web-based survey was developed and deployed. RESULTS: One hundred eight EMS stations were contacted with the survey. Sixty-eight providers responded; majority were emergency medical paramedics (73.1%). Most of the stations surveyed did not have a pediatric trauma center (66.2%). When treating children younger than 3 years, half of the respondents stated they did not know of a specific cervical spine clearance criterion; 59.3% felt that cervical spine immobilization was required "sometimes," and 40.0% were unaware of the state's EMS pediatric cervical spine clearance algorithm; 93.9% of EMS providers felt that an age-based algorithm for cervical spine clearance in children would be useful. CONCLUSIONS: In this statewide survey involving prehospital EMS providers, we found that pediatric cervical spine clearance and immobilization practices, even within a specific geographic location, remain inconsistent.


Asunto(s)
Servicios Médicos de Urgencia , Auxiliares de Urgencia , Traumatismos Vertebrales , Vértebras Cervicales/lesiones , Niño , Estudios Transversales , Humanos , Inmovilización , Traumatismos Vertebrales/terapia , Encuestas y Cuestionarios
15.
J Manuf Sci Eng ; 143(4)2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34092998

RESUMEN

Manufacturing processes have become increasingly sophisticated leading to greater usage of robotics. Sustaining successful manufacturing robotic operations requires a strategic maintenance program. Without careful planning, maintenance can be very costly. To reduce maintenance costs, manufacturers are exploring how they can assess the health of their robot workcell operations to enhance their maintenance strategies. Effective health assessment relies upon capturing appropriate data and generating intelligence from the workcell. Multiple data streams relevant to a robot workcell may be available including robot controller data, a supervisory programmable logic controller data, maintenance logs, process and part quality data, and equipment and process fault and failure data. These data streams can be extremely informative, yet the massive volume and complexity of this data can be overwhelming, confusing, and sometimes paralyzing. Researchers at the National Institute of Standards and Technology have developed a test method and companion sensor to assess the health of robot workcells which will yield an additional and unique data stream. The intent is that this data stream can either serve as a surrogate for larger data volumes to reduce the data collection and analysis burden on the manufacturer, or add more intelligence to assessing robot workcell health. This article presents the most recent effort focused on verifying the companion sensor. Results of the verification test process are discussed along with preliminary results of the sensor's performance during verification testing. Lessons learned indicate that the test process can be an effective means of quantifying the sensor's measurement capability particularly after test process anomalies are addressed in future efforts.

16.
PLoS Pathog ; 14(4): e1006972, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29614112

RESUMEN

Arthropod vectors have multiple physical and immunological barriers that impede the development and transmission of parasites to new vertebrate hosts. These barriers include the peritrophic matrix (PM), a chitinous barrier that separates the blood bolus from the midgut epithelia and modulates vector-pathogens interactions. In tsetse flies, a sleeve-like PM is continuously produced by the cardia organ located at the fore- and midgut junction. African trypanosomes, Trypanosoma brucei, must bypass the PM twice; first to colonize the midgut and secondly to reach the salivary glands (SG), to complete their transmission cycle in tsetse. However, not all flies with midgut infections develop mammalian transmissible SG infections-the reasons for which are unclear. Here, we used transcriptomics, microscopy and functional genomics analyses to understand the factors that regulate parasite migration from midgut to SG. In flies with midgut infections only, parasites fail to cross the PM as they are eliminated from the cardia by reactive oxygen intermediates (ROIs)-albeit at the expense of collateral cytotoxic damage to the cardia. In flies with midgut and SG infections, expression of genes encoding components of the PM is reduced in the cardia, and structural integrity of the PM barrier is compromised. Under these circumstances trypanosomes traverse through the newly secreted and compromised PM. The process of PM attrition that enables the parasites to re-enter into the midgut lumen is apparently mediated by components of the parasites residing in the cardia. Thus, a fine-tuned dialogue between tsetse and trypanosomes at the cardia determines the outcome of PM integrity and trypanosome transmission success.


Asunto(s)
Cardias/parasitología , Insectos Vectores , Trypanosoma/patogenicidad , Tripanosomiasis/transmisión , Moscas Tse-Tse/parasitología , Animales , Cardias/inmunología , Tracto Gastrointestinal/parasitología , Glándulas Salivales/parasitología , Tripanosomiasis/inmunología , Moscas Tse-Tse/inmunología
17.
N Engl J Med ; 375(26): 2550-2560, 2016 12 29.
Artículo en Inglés | MEDLINE | ID: mdl-28029918

RESUMEN

BACKGROUND: Effective medical therapies are lacking for the treatment of neurofibromatosis type 1-related plexiform neurofibromas, which are characterized by elevated RAS-mitogen-activated protein kinase (MAPK) signaling. METHODS: We conducted a phase 1 trial of selumetinib (AZD6244 or ARRY-142886), an oral selective inhibitor of MAPK kinase (MEK) 1 and 2, in children who had neurofibromatosis type 1 and inoperable plexiform neurofibromas to determine the maximum tolerated dose and to evaluate plasma pharmacokinetics. Selumetinib was administered twice daily at a dose of 20 to 30 mg per square meter of body-surface area on a continuous dosing schedule (in 28-day cycles). We also tested selumetinib using a mouse model of neurofibromatosis type 1-related neurofibroma. Response to treatment (i.e., an increase or decrease from baseline in the volume of plexiform neurofibromas) was monitored by using volumetric magnetic resonance imaging analysis to measure the change in size of the plexiform neurofibroma. RESULTS: A total of 24 children (median age, 10.9 years; range, 3.0 to 18.5) with a median tumor volume of 1205 ml (range, 29 to 8744) received selumetinib. Patients were able to receive selumetinib on a long-term basis; the median number of cycles was 30 (range, 6 to 56). The maximum tolerated dose was 25 mg per square meter (approximately 60% of the recommended adult dose). The most common toxic effects associated with selumetinib included acneiform rash, gastrointestinal effects, and asymptomatic creatine kinase elevation. The results of pharmacokinetic evaluations of selumetinib among the children in this trial were similar to those published for adults. Treatment with selumetinib resulted in confirmed partial responses (tumor volume decreases from baseline of ≥20%) in 17 of the 24 children (71%) and decreases from baseline in neurofibroma volume in 12 of 18 mice (67%). Disease progression (tumor volume increase from baseline of ≥20%) has not been observed to date. Anecdotal evidence of decreases in tumor-related pain, disfigurement, and functional impairment was observed. CONCLUSIONS: Our early-phase data suggested that children with neurofibromatosis type 1 and inoperable plexiform neurofibromas benefited from long-term dose-adjusted treatment with selumetinib without having excess toxic effects. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT01362803 .).


Asunto(s)
Bencimidazoles/administración & dosificación , Bencimidazoles/farmacocinética , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Neurofibroma Plexiforme/tratamiento farmacológico , Neurofibromatosis 1/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacocinética , Adolescente , Animales , Bencimidazoles/efectos adversos , Niño , Preescolar , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Ratones , Neurofibroma Plexiforme/diagnóstico por imagen , Inhibidores de Proteínas Quinasas/efectos adversos
18.
Pediatr Blood Cancer ; 66(3): e27532, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30393936

RESUMEN

Head and neck rhabdomyosarcoma lymph node staging is challenging due to varied patterns of lymphatic drainage and the suboptimal predictive value of available imaging modalities. Furthermore, regional relapse rates are unacceptably high, and the toxicity of empiric radiation is undesirable in the pediatric and young adult population. In an attempt to improve locoregional control without excess morbidity, we have adopted routine sentinel lymph node biopsy in head and neck rhabdomyosarcoma, which is safe and feasible in pediatric patients. Of six procedures reported here, pathologic findings led to intensification of regional and/or systemic therapy in two patients.


Asunto(s)
Neoplasias de Cabeza y Cuello/patología , Rabdomiosarcoma/patología , Biopsia del Ganglio Linfático Centinela/métodos , Ganglio Linfático Centinela/patología , Adolescente , Adulto , Niño , Preescolar , Femenino , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Lactante , Masculino , Pronóstico , Estudios Prospectivos , Rabdomiosarcoma/cirugía , Ganglio Linfático Centinela/cirugía , Adulto Joven
19.
Proc Natl Acad Sci U S A ; 113(25): 6961-6, 2016 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-27185908

RESUMEN

Tsetse flies are biological vectors of African trypanosomes, the protozoan parasites responsible for causing human and animal trypanosomiases across sub-Saharan Africa. Currently, no vaccines are available for disease prevention due to antigenic variation of the Variant Surface Glycoproteins (VSG) that coat parasites while they reside within mammalian hosts. As a result, interference with parasite development in the tsetse vector is being explored to reduce disease transmission. A major bottleneck to infection occurs as parasites attempt to colonize tsetse's midgut. One critical factor influencing this bottleneck is the fly's peritrophic matrix (PM), a semipermeable, chitinous barrier that lines the midgut. The mechanisms that enable trypanosomes to cross this barrier are currently unknown. Here, we determined that as parasites enter the tsetse's gut, VSG molecules released from trypanosomes are internalized by cells of the cardia-the tissue responsible for producing the PM. VSG internalization results in decreased expression of a tsetse microRNA (mir-275) and interferes with the Wnt-signaling pathway and the Iroquois/IRX transcription factor family. This interference reduces the function of the PM barrier and promotes parasite colonization of the gut early in the infection process. Manipulation of the insect midgut homeostasis by the mammalian parasite coat proteins is a novel function and indicates that VSG serves a dual role in trypanosome biology-that of facilitating transmission through its mammalian host and insect vector. We detail critical steps in the course of trypanosome infection establishment that can serve as novel targets to reduce the tsetse's vector competence and disease transmission.


Asunto(s)
Glicoproteínas de Membrana , Moscas Tse-Tse/inmunología , África del Sur del Sahara , Animales , Humanos , Mamíferos/inmunología , Trypanosoma brucei brucei/genética , Tripanosomiasis , Tripanosomiasis Africana/parasitología , Glicoproteínas Variantes de Superficie de Trypanosoma/genética
20.
PLoS Genet ; 12(12): e1006501, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27997549

RESUMEN

Neuroblastoma is characterized by a relative paucity of recurrent somatic mutations at diagnosis. However, recent studies have shown that the mutational burden increases at relapse, likely as a result of clonal evolution of mutation-carrying cells during primary treatment. To inform the development of personalized therapies, we sought to further define the frequency of potentially actionable mutations in neuroblastoma, both at diagnosis and after chemotherapy. We performed a retrospective study to determine mutation frequency, the only inclusion criterion being availability of cancer gene panel sequencing data from Foundation Medicine. We analyzed 151 neuroblastoma tumor samples: 44 obtained at diagnosis, 42 at second look surgery or biopsy for stable disease after chemotherapy, and 59 at relapse (6 were obtained at unknown time points). Nine patients had multiple tumor biopsies. ALK was the most commonly mutated gene in this cohort, and we observed a higher frequency of suspected oncogenic ALK mutations in relapsed disease than at diagnosis. Patients with relapsed disease had, on average, a greater number of mutations reported to be recurrent in cancer, and a greater number of mutations in genes that are potentially targetable with available therapeutics. We also observed an enrichment of reported recurrent RAS/MAPK pathway mutations in tumors obtained after chemotherapy. Our data support recent evidence suggesting that neuroblastomas undergo substantial mutational evolution during therapy, and that relapsed disease is more likely to be driven by a targetable oncogenic pathway, highlighting that it is critical to base treatment decisions on the molecular profile of the tumor at the time of treatment. However, it will be necessary to conduct prospective clinical trials that match sequencing results to targeted therapeutic intervention to determine if cancer genomic profiling improves patient outcomes.


Asunto(s)
Evolución Clonal/genética , Mutación/genética , Recurrencia Local de Neoplasia/genética , Neuroblastoma/genética , Proteínas Tirosina Quinasas Receptoras/genética , Adolescente , Adulto , Anciano , Quinasa de Linfoma Anaplásico , Niño , Preescolar , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Recién Nacido , Sistema de Señalización de MAP Quinasas/genética , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/patología , Neuroblastoma/cirugía , Estudios Retrospectivos , Proteínas ras/genética
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