RESUMEN

Objetivo: Determinar la prevalencia de trastornos del gusto en pacientes niños y adolescentes diagnosticados con infección por coronavirus, a través de la evidencia en la literatura científica. Materiales y métodos: Una revisión sistemática de los artículos publicados entre el 19 de diciembre del 2019 y el 20 de diciembre del 2020 en las bases de datos Medline, Lilacs, BVS, Cochrane, SCOPUS y ScienceDirect. La estrategia de búsqueda de información se basó en el diagrama de flujo clásico de PRISMA. Para la evaluación del riesgo de sesgo, se usó la escala Newcastle-Ottawa. Resultados: Se encontraron 443 artículos en seis bases de datos y se incluyó un total de 7 artículos después de la evaluación, según los criterios de selección. Los artículos abordaron la variable de trastornos del gusto en tres formas: ageusia, disgeusia e hipogeusia, y se halló que esta manifestación clínica estaba presente desde los inicios de la infección. Conclusiones: Se ha encontrado una prevalencia de trastornos del gusto en niños y adolescentes diagnosticados con infección por coronavirus desde un 3,3% hasta un 26,9%. (AU)

Aim: To assess the prevalence of taste disorders in children and adolescents diagnosed with coronavirus infection according to the evidence reported in the scientific literature. Materials and Methods: A systematic review of articles published between December 19, 2019, and December 20, 2020 in the Medline, Lilacs, BVS, Cochrane, SCOPUS and ScienceDirect databases. The information search strategy was based on the classic PRISMA flow diagram. The Newcastle-Ottawa scale was used to assess the risk of bias. Results: 443 articles were found in six databases, and a total of 7 articles were included after evaluation according to the selection criteria. The articles addressed the variable of taste disorders in three ways: ageusia, dysgeusia and hypogeusia; finding that this clinical manifestation was present from the beginning of the infection. Conclusions: The prevalence of taste disorders in children and adolescents diagnosed with coronavirus infection is from 3.3% to 26.9%. (AU)

Asunto(s)

RESUMEN

Aim: To assess the prevalence of taste disorders in children and adolescents diagnosed with coronavirus infection according to the evidence reported in the scientific literature. Materials and Methods: A systematic review of articles published between December 19, 2019, and December 20, 2020 in the Medline, Lilacs, BVS, Cochrane, SCOPUS and ScienceDirect databases. The information search strategy was based on the classic PRISMA flow diagram. The Newcastle-Ottawa scale was used to assess the risk of bias. Results: 443 articles were found in six databases, and a total of 7 articles were included after evaluation according to the selection criteria. The articles addressed the variable of taste disorders in three ways: ageusia, dysgeusia and hypogeusia; finding that this clinical manifestation was present from the beginning of the infection. Conclusions: The prevalence of taste disorders in children and adolescents diagnosed with coronavirus infection is from 3.3% to 26.9%.

RESUMEN

Mycobacteriophages Deby, LaterM, LilPharaoh, Paola, SgtBeansprout, and Sulley were isolated from soil using Mycobacterium smegmatis mc2155. Genomic analysis indicated that they belong to subclusters K1 and K5. Their genomic architectures are typical of cluster K mycobacteriophages, with most variability occurring on the right end of the genome sequence.

RESUMEN

Resumen Objetivo: Comparar la resistencia al desplazamiento de cuatro agentes cementantes. Material y métodos: Se realizó una investigación prospectiva, transversal y experimental en la que se evaluaron cuatro agentes cementantes, tres de ellos resinosos autoadhesivos de polimerización dual y con contenido de MDP (10-metacriloxidecil dihidrógeno fosfato) y un ionómero de vidrio convencional. Se realizaron 40 muestras de zirconia parcialmente estabilizada con itrio, se dividieron en cuatro grupos, cada uno de ellos fue tratado de acuerdo con las indicaciones del fabricante del cemento a estudiar, se realizaron las muestras, se almacenaron en humedad al 100% en una cámara a una temperatura de 37 °С durante 24 horas para después ser sometidas a pruebas mecánicas de desprendimiento por cizallamiento a una velocidad de 1 mm por minuto en la máquina universal de pruebas mecánicas. Resultados: La muestras de ionómero de vidrio fracasaron antes de ser llevadas a la maquina universal, entre los otros tres cementos no existe diferencia estadísticamente significativa. Conclusiones: La capacidad de adhesión de ionómero de vidrio a la zirconia es nula o muy baja. Igualmente los cementos resinosos que contengan en su fórmula MDP, ya sea en su agente de acoplamiento o en la fórmula misma de los cementos, son en la actualidad la mejor alternativa para incrementar la adhesión a una superficie de zirconia.

Abstract Objective: To compare displacement resistance of four cementing agents. Material and methods: An experimental, cross-sectioned prospective research was conducted to assess four cementing agents. Three agents were resinous, self-adhesive, dual polymerization cements containing MDP (10-metacryloxydecyl dihydrogen phosphate), and the remaining was a conventional glass ionomer cement. In the experiment, 40 samples of zirconia partially stabilized with yttrium were prepared. All samples were treated following their specific manufacturer's instructions. Samples were prepared, they were then stored at 100% humidity in a temperature chamber at 37 °С for 24 hours; after this, samples were subjected to shearing detachment mechanical tests at a 1 mm per minute speed in a universal machine for mechanical testing. Results: Glass ionomer samples failed before being taken to the universal testing machine. Remaining three cements did not show statistically significant differences. Conclusions: Adhesion capacity of glass ionomer to zirconia is nil or extremely low. Likewise, resinous cements containing MDP in their formula, either in their bonding agent or in the cement formulation itself, are presently the best alternative to increase adhesion to a zirconia structure.

RESUMEN

The possibility to reduce the culture time and volume of blood and reagents required for the chemical Premature Chromosome Condensation (PCC) assay is demonstrated in this work. Peripheral whole blood was exposed to gamma radiation (1-20 Gy). Lymphocytes were cultured for 40 h, using 50 µl of blood and 450 µl of culture medium. The dose-response curves were adjusted, using length ratio (LR) of the longest to the shortest chromosome piece, and the frequency of rings per cell. No statistical differences were found between the results obtained with this method and those reported with the classical PCC assay culture. The minimization of culture time and reagents in combination with the automatic measurement of the LR of the chromosome pieces, or the scoring of rings, can be a valuable biodosimetry tool in a mass casualty scenario.

Asunto(s)

RESUMEN

Mitotic Index (MI) estimation expressed as percentage of mitosis plays an important role as quality control endpoint. To this end, MI is applied to check the lot of media and reagents to be used throughout the assay and also to check cellular viability after blood sample shipping, indicating satisfactory/unsatisfactory conditions for the progression of cell culture. The objective of this paper was to apply the CellProfiler open-source software for automatic detection of mitotic and nuclei figures from digitized images of cultured human lymphocytes for MI assessment, and to compare its performance to that performed through semi-automatic and visual detection. Lymphocytes were irradiated and cultured for mitosis detection. Sets of images from cultures were analyzed visually and findings were compared with those using CellProfiler software. The CellProfiler pipeline includes the detection of nuclei and mitosis with 80% sensitivity and more than 99% specificity. We conclude that CellProfiler is a reliable tool for counting mitosis and nuclei from cytogenetic images, saves considerable time compared to manual operation and reduces the variability derived from the scoring criteria of different scorers. The CellProfiler automated pipeline achieves good agreement with visual counting workflow, i.e. it allows fully automated mitotic and nuclei scoring in cytogenetic images yielding reliable information with minimal user intervention.

Asunto(s)

RESUMEN

The fast assessment of the dose received by exposed persons is crucial in radiological accidents, so the 48 h of cell culture in conventional cytogenetic dosimetry in addition to some limitations after high doses becomes a disadvantage. The premature chromosome condensation (PCC) assay permits to analyse enough cells after high radiation exposure, and the score of PCC-R may reduce the culture time up to 40-42 h. Peripheral whole-blood samples were exposed to 1-10 Gy of gamma radiation and cultured during 40 and 42 h. No statistical difference between frequencies was obtained between 40, 42 and 48 h of culture time, and PCC index decreased with the increase of the dose and increased with the culture time. The protocol proposed allows reduce the culture time down to 40 or 42 h when using the PCC-R assay with adequate precision in dose estimation.

Asunto(s)

RESUMEN

The combination of automatic image acquisition and automatic image analysis of premature chromosome condensation (PCC) spreads was tested as a rapid biodosimeter protocol. Human peripheral lymphocytes were irradiated with (60)Co gamma rays in a single dose of between 1 and 20 Gy, stimulated with phytohaemaglutinin and incubated for 48 h, division blocked with Colcemid, and PCC-induced by Calyculin A. Images of chromosome spreads were captured and analysed automatically by combining the Metafer 4 and CellProfiler platforms. Automatic measurement of chromosome lengths allows the calculation of the length ratio (LR) of the longest and the shortest piece that can be used for dose estimation since this ratio is correlated with ionizing radiation dose. The LR of the longest and the shortest chromosome pieces showed the best goodness-of-fit to a linear model in the dose interval tested. The application of the automatic analysis increases the potential use of the PCC method for triage in the event of massive radiation causalities.

Asunto(s)

RESUMEN

BACKGROUND: Dexamethasone is more efficacious than prednisone in the treatment of acute lymphoblastic leukemia (ALL), but has also been associated with greater toxicity. We compared neuropsychological outcomes for patients treated on DFCI ALL Consortium Protocol 00-01, which included a randomized comparison of the two steroid preparations during post-induction therapy in children and adolescents with ALL. PROCEDURE: Between 2000 and 2005, 408 children with standard-risk or high-risk ALL treated on Dana-Farber Cancer Institute Consortium Protocol 00-01 were randomly assigned to prednisone or dexamethasone administered as 5-day pulses every 3 weeks for 2 years, beginning at week 7 of treatment. Blinded neuropsychological testing was completed for 170 randomized patients (prednisone, N = 76; dexamethasone, N = 94), all of whom were in continuous complete remission after completion of therapy. RESULTS: Outcomes were comparable for most variables, although patients on the dexamethasone arm performed more poorly on a measure of fluid reasoning (P = 0.02). They also tended to be more likely to be enrolled in special education (dexamethasone, 33% vs. prednisone, 20%, P = 0.09). CONCLUSIONS: Dexamethasone has well documented benefit in treatment of ALL. Although formal testing provided little indication of increased risk for neurotoxicity relative to prednisone, the somewhat greater utilization of special education services by patients treated with dexamethasone merits further investigation.

Asunto(s)

RESUMEN

The estimation of the dose and the irradiated fraction of the body is important information in the primary medical response in case of a radiological accident. The PCC-R assay has been developed for high-dose estimations, but little attention has been given to its applicability for partial-body irradiations. In the present work we estimated the doses and the percentage of the irradiated fraction in simulated partial-body radiation exposures at high doses using the PCC-R assay. Peripheral whole blood of three healthy donors was exposed to doses from 0-20 Gy, with 6°Co gamma radiation. To simulate partial body irradiations, irradiated and non-irradiated blood was mixed to obtain proportions of irradiated blood from 10-90%. Lymphocyte cultures were treated with Colcemid and Calyculin-A before harvest. Conventional and triage scores were performed for each dose, proportion of irradiated blood and donor. The Papworth's u test was used to evaluate the PCC-R distribution per cell. A dose-response relationship was fitted according to the maximum likelihood method using the frequencies of PCC-R obtained from 100% irradiated blood. The dose to the partially irradiated blood was estimated using the Contaminated Poisson method. A new D0 value of 10.9 Gy was calculated and used to estimate the initial fraction of irradiated cells. The results presented here indicate that by PCC-R it is possible to distinguish between simulated partial- and whole-body irradiations by the u-test, and to accurately estimate the dose from 10-20 Gy, and the initial fraction of irradiated cells in the interval from 10-90%.

Asunto(s)

RESUMEN

BACKGROUND: Children treated for acute lymphoblastic leukemia (ALL) as High Risk (HR) patients may be more vulnerable to neurocognitive late effects because of the greater intensity of their therapy. We compared neuropsychological outcomes in children treated for Standard Risk (SR) or HR ALL on Dana-Farber Cancer Institute (DFCI) Consortium ALL Protocol 95-01. We also evaluated their performance relative to normative expectations. PROCEDURE: Between 1996 and 2000, 498 children with newly diagnosed ALL were treated on Protocol 95-01, 298 of whom were eligible for neuropsychological follow-up. A feature of this protocol was modification of risk group criteria to treat more children as SR rather than HR patients, intended to minimize toxicities. Testing was completed at a median of 5.3 years post-diagnosis for 211 patients (70.8%; ages 6-25 years; 45.5% male; 40% HR), all of whom were in continuous complete remission. RESULTS: Test scores for both groups were generally at or above normative expectation, with the exception of verbal working memory, processing complex visual information, and parent ratings of metacognitive skills. After adjusting for covariates, the SR group performed better on measures of IQ and academic achievement, working memory and visual learning. Effect sizes, however, were only in the small to moderate range. CONCLUSIONS: HR patients exhibited neuropsychological deficits relative to SR patients, though the differences were modest in degree. Modification of the risk group criteria to treat more children on the SR protocol therefore likely afforded some benefit in terms of neurocognitive late effects.

Asunto(s)

RESUMEN

The survivorship of children diagnosed with cancer has risen during the last decade. After the end of treatment those children and their families return to the community where another period of crisis unfolds. In this article, the findings of a larger qualitative study in Puerto Rico related to the return to the community of these patients and their families are discussed, including financial difficulties, the burden of responsibility, and transition to school. These findings provide a rationale for the implementation of a bio-psycho-social model of health that emphasizes reciprocal interactions among the multiple systems in which these families are embedded.

Asunto(s)

RESUMEN

One of the difficulties in the comparison of results between laboratories working with the comet assay is the great diversity of parameters used to express DNA damage and the lack of conversion factors between the majority of them. Here we report a scorer-independent conversion curve to transform the values of DNA damage reported in arbitrary units (AU) into estimated percentage of DNA in the tail (E%T), and the results obtained in an intercomparison exercise where the effectiveness of this curve and two others proposed in the literature (E%T=AU/4 and E%T=(AU/5)+10) were tested. To obtain the conversion curve, human lymphocytes were first treated with radiation or H(2)O(2). Percentage of DNA in tail (%T) was then measured in 2100 comets (300 comets per treatment) using Casp image analysis software. Subsequently, using these values of %T, categories of 0, 1, 2, 3, and 4 were assigned to comets with %T [0-1), [1-25), [25-45), [45-70), and >70, and DNA damage was calculated in AU, as usual. DNA damage was induced in the interval 24-315AU (1.54-65.23%T). The best-fit conversion curve obtained by regression analysis was E%T=(AU-25.87)/4.46. In the intercomparison exercise, ten scorers from nine laboratories analyzed the same comet images (recorded on a compact disc) visually. The values reported in comet categories were transformed into AU and subsequently into E%T, using the three approaches mentioned above. The best agreement between E%T and %T measured by the software (S%T) was obtained with the conversion curve reported here, where the slope of E%T versus S%T from the ten scorers was not different from 1. Using this conversion curve, the overall mean difference between E%T and S%T was 1.4±2.62 and 57 (81%) of E%T values differ from S%T by less than 5 units. These findings show the strength of the scorer-independent conversion curve as a tool to compare results reported in AU or %T by different laboratories.

Asunto(s)

RESUMEN

Although pediatric cancer treatment has been reviewed by several authors, the lived experiences of children undergoing this process have seldom been discussed in the literature. The data for this article were obtained from a larger qualitative study that provided a collective view of the pediatric cancer experience at San Jorge Children's Hospital in Puerto Rico. In this article, findings that are directly related to the hospitalization process of these young patients are described, including the hospital as a safe haven, dealing with pain, taking control, and thriving in adversity. These findings provide a rationale for the development of a biopsychosocial model of health that emphasizes reciprocal interactions among the biological, psychological, social, cultural, and spiritual dimensions that influence health.

Asunto(s)

RESUMEN

Pediatric cancer survivors are a growing group whose needs extend to multiple contexts and systems. Most studies dealing with the emotional sequelae of childhood cancer have neglected patients' and parents' perspectives. Few have dealt with issues faced by the treatment team. Our research constitutes the first attempt to gather a collective view of such experience in Puerto Rico. Using a phenomenological approach, in-depth interviews were conducted with acute lymphoblastic leukemia (ALL) patients, their mothers, and their oncology treatment team (18) at a children's hospital in Puerto Rico. Analysis followed the model proposed by Strauss and Corbin. In this article, findings directly associated with the cultural aspects of the Puerto Rican cancer experience are presented, including the mother's role--devotion and abandonment; the father's role--masculine vulnerability; and the family paradox. Mothers' protagonism was the central theme that emerged from these three categories.

Asunto(s)

RESUMEN

PURPOSE: We evaluated late neuropsychological toxicity in children treated for standard-risk acute lymphoblastic leukemia (ALL) who were randomly assigned to receive either cranial radiation therapy (CRT) with double intrathecal (IT) chemotherapy or intensive triple IT chemotherapy (no CRT) as CNS-directed therapy. PATIENTS AND METHODS: Between 1996 and 2000, 164 children with standard-risk ALL treated on Dana-Farber Cancer Institute Consortium Protocol 95-01 were randomly assigned to receive either 18 Gy CRT delivered in twice daily fractions (0.9 [DOSAGE ERROR CORRECTED] Gy) with double IT therapy (methotrexate and cytarabine) or intensive triple IT drug (methotrexate, cytarabine and hydrocortisone) without CRT. Neuropsychological testing was completed at a median 6 years postdiagnosis for 79 children (CRT, n = 39; triple IT, n = 40), all of whom were in continuous complete remission. RESULTS: Cognitive function for both groups was solidly in the average range, with no consistent group differences in basic cognitive skills. Children treated on the CRT plus double IT arm did, however, exhibit less fluent output and were less effective at modulating their behavior by parent report. CONCLUSION: This randomized trial revealed only subtle differences 6 years after diagnosis between children who received CNS therapy as CRT plus double IT drug or as intensive triple IT drug. In most situations where comparable therapeutic efficacy can be achieved without CRT, it is preferable to do so. Where therapeutically necessary, however, CRT at lower doses may not add risk for significant neurotoxicity.

Asunto(s)

RESUMEN

Silver stain offers the possibility to stain comets permanently, but up to now it was impossible to measure the majority of the comet parameters, because the distinction between head and tail was not recognised by software. Here, we report a silver staining protocol that allows the measurement of comet parameters using the free Internet software CASP. We validated the silver stain protocol by comparing the behaviour of the parameter '% DNA in tail' in silver and fluorescent stained comets. The range of % DNA in tail for different visual categories of damage in silver stained comets was similar to that reported with fluorescence staining. The range was for category 0 (no damage), <1%; category 1 (low damage), 1-25%; category 2 (medium damage), >25-45%; category 3 (high damage), >45-70%; category 4 (very high damage), >70%. The mean of % DNA in tail in silver stained comets was also similar to that reported with fluorescence staining. The mean was for category 0, 0.4+/-0.34%; category 1, 12+/-7%; category 2, 37+/-4%; category 3, 57+/-5% and category 4, 83+/-6%. Others comet parameters such as tail length, tail moment and Olive tail moment can be also measured. The silver staining protocol reported here opens new opportunities for those working in the assay without fluorescent microscope as the measurement of comet parameters using free Internet software and conventional microscope becomes possible.

Asunto(s)

RESUMEN

PURPOSE: We evaluated 8-year survival and late neuropsychologic toxicity in children with acute lymphoblastic leukemia treated in a randomized clinical trial to test whether hyperfractionated (twice daily) cranial radiation therapy (CRT) can reduce incidence and severity of late toxicities associated with 18 Gy of CRT. PATIENTS AND METHODS: Between 1987 and 1995, 369 children treated on two consecutive Dana-Farber Cancer Institute Consortium protocols for high-risk acute lymphoblastic leukemia were randomly assigned to conventionally fractionated CRT (CFX) or hyperfractionated CRT (HFX) to a total dose of 18 Gy. Neuropsychologic testing was completed for 125 of 287 children in continuous complete remission. Event-free and overall survival, as well as neuropsychologic function, were compared for the two arms of the protocol. RESULTS: Eight-year event-free survival (+/- SE) was 80% +/- 3% for children randomly assigned to CFX and 72% +/- 3% for HFX (P =.06). Overall survival was 85% +/- 3% for CFX and 78% +/- 3% for HFX (P =.06). CNS relapses occurred in 2.8% of patients receiving CFX and 2.7% receiving HFX (P =.99). Cognitive function for both groups was solidly in the average range, with no group differences in intelligence, academic achievement, visuospatial reasoning, or verbal learning. Children on the HFX arm exhibited a modest advantage for visual memory (P <.05). CONCLUSION: HFX provides no benefit in terms of cognitive late effects and may compromise antileukemic efficacy. HFX should not be substituted for conventionally dosed CRT in children who require radiation therapy for treatment of acute lymphoblastic leukemia.

Asunto(s)

RESUMEN

La gran heterogeneidad ambiental de viviendas y barrios en los centros urbanos donde se cria Aedes aegypti, principal vector del dengue, junto con la escasez de recursos y de personal entrenado en el control de mosquitos constituyen retos para cualquier iniciativa destinada a controlar el dengue hemorragico (DH). Una adecuada vigilancia epidemiologica puede servir de base para comenzar a estratificar los centros urbanos e identificar las zonas criticas donde deben concentrarse las tareas de control. En este estudio, se estratifico una ciudad hiperendemica en dengue hemorragico (Maracay, Venezuela) con la ayuda de un sistema de informacion geografica (SIG) y el analisis de la persistencia, la incidencia y la prevalencia del dengue mediante diagnosticos clinicos registrados de 1993 a 1998. Maracay tiene cerca de un millon de habitantes que viven en unos 349 barrios de 6 poblaciones que integran el Area Metropolitana, donde se notificaron 10.576 casos de dengue, 2.593 casos de DH y 8 defunciones. La incidencia de DH mostro una relacion directa con la incidencia del dengue, el numero de habitantes y la densidad poblacional. El patron espacial de la incidencia del dengue fue estable durante los anos estudiados y se encontraron relaciones positivas y significativas de la incidencia del dengue por barrio entre pares de anos. La persistencia del dengue se relaciono directamente con la incidencia mensual por barrio. Estos patrones espaciales facilitaron la estratificacion de la ciudad en tres estratos: 68 barrios sin dengue aparente, 226 barrios con baja persistencia y prevalencia, y 55 barrios con alta persistencia y prevalencia. Se recomienda otorgar alta prioridad de control a estos 55 barrios que ocupan 35 por ciento del area urbana y presentaron 70 por ciento de todos los casos de dengue

Any effort to control dengue hemorrhagic fever (DHF) faces a number of challenges. Among these are the great environmental heterogeneity of homes and neighborhoods in urban centers where the primary dengue vector, Aedes aegypti, breeds, as well as shortages of resources and of personnel trained in mosquito control. Adequate epidemiological surveillance could serve as a basis to begin to stratify urban communities and identify the areas in them where control efforts should be focused. In this study we stratified Maracay, Venezuela, a city with hyperendemic dengue hemorrhagic fever, using a geographic information system and analyzing the persistence, incidence, and prevalence of dengue, by means of clinical diagnoses reported from 1993 through 1998.Maracay has around one million inhabitants living in some 349 neighborhoods in the six communities that make up the greater Maracay metropolitan area. During that 1993­1998 period the Maracay area reported 10 576 cases of dengue, 2 593 cases of DHF, and 8 deaths. The incidence of DHF was related to the incidence of dengue, the number of inhabitants in an area, and population density. The spatial pattern of dengue incidence was stable over the years that were studied, and significant, positive relationships were found between pairs of years and the incidence of dengue by neighborhood. The persistence of dengue was related directly to monthly incidence by neighborhood. These spatial patterns helped to divide the city into three strata: 68 neighborhoods without apparent dengue, 226 neighborhoods with low persistence and prevalence, and 55 neighborhoods with high persistence and prevalence. We recommend giving the highest priority for control efforts to these 55 neighborhoods, which make up just 35% of the Maracay urban area but had 70% of all the reported dengue cases

Asunto(s)

Asunto(s)