Screening for chemicals with thyroid hormone-disrupting effects using zebrafish embryo.

Thyroid disruption is an increasingly recognized issue in the use and development of chemicals and new drugs, especially to help toxicologist to complement the reproductive and developmental toxicology information of chemicals. Still, adequate assessment methods are scarce and often suffer a trade-off between physiological relevance and labor- and cost-intensive assays. Here, we present a tiered approach for a medium-throughput screening of chemicals to identify their thyroid disrupting potential in zebrafish embryos as a New Approach Methodology (NAM). After identifying the maximum tolerated concentrations, we exposed zebrafish larvae to sub-adverse effect levels of the reference compounds benzophenone-2, bisphenol A, phenylthiourea, potassium perchlorate, propylthiouracil, and phloroglucinol to exclude any systemic toxicity. Applying the transgenic zebrafish line that carries a gene for the red fluorescence protein (Tg(tg:mCherry)) under the thyroglobulin promoter, we could identify the thyroid disrupting effects of the chemicals by a time and cost-effective image analysis measuring the fluorescence levels in the thyroid glands. Our observations could be confirmed by altered expression patterns of genes involved in the hypothalamus-pituitary-thyroid (HPT) axis. Finally, to anchor the observed thyroid disruption, we determined some changes in the Thyroid hormone levels of triiodothyronine (T3) and Thyroxine (T4) using a newly developed liquid chromatography mass spectrometric (LCMS) method. The presented approach carries the potential to extend the toolbox for legislative authorities and chemical producers for the assessment of thyroid-specific endocrine disruption and to overcome current challenges in the evaluation of endocrine disruptors.

Posible influencia de factores no controlados en las concentraciones séricas de uracilo / Possible influence of uncontrolled factors on serum uracil concentrations

Antecedentes y objetivos: el déficit de dihidropirimidina deshidrogenasa (DPD) se ha asociado con un mayor riesgo de toxicidad tras exposición a fluoropirimidinas (FP). La determinación de las concentraciones plasmáticas de uracilo endógeno (U) es la prueba recomendada para identificar el déficit de DPD. Sin embargo, el valor de U puede verse afectado por diversos factores. El objetivo fue determinar la concentración sérica de U en una población candidata a recibir tratamiento con FP y comprobar si su distribución era compatible con la prevalencia del déficit parcial de DPD estimada en población caucásica. Material y métodos: estudio observacional prospectivo en el que se incluyeron pacientes oncológicos candidatos a tratamiento con FP. Para la determinación analítica se empleó un sistema Dionex Ultimate 3000 UHPLC, acoplado a un espectrómetro de masas cuadrupolo-orbitrap híbrido Q-exactive. Resultados: se incluyeron 77 pacientes con una edad media de 71 años. La media y la mediana de las concentraciones séricas de U fue 30,4 y 24,0 ng/ml, respectivamente. El rango fue de 7,1 a 139,7 ng/ml. Un 79,2% de los pacientes presentó un nivel de U comprendido entre 16 y 150 ng/ml, mostrando una diferencia estadísticamente significativa al compararlo con la prevalencia estimada en población caucásica (8%) (p-valor <0,0001). El método analítico empleado tiene un coeficiente de correlación R2 > 0,99 y un límite de detección <0,2 ng/ml. Conclusiones: es necesario llevar a cabo más estudios con un diseño dirigido a establecer las condiciones óptimas relativas al pretratamiento de las muestras a fin de evitar o minimizar la influencia de estos factores sobre los valores del analito. (AU)

Background and objective: dihydropyridine dehydrogenase (DPD) deficiency has been associated with an increased risk of toxicity after exposure to fluoropyrimidines (FP). Determination of endogenous uracil (U) plasma concentrations is the recommended test to identify DPD deficiency. However, the value of U can be affected by various factors. The objective was to determine the serum concentration of U in a population candidate to receive treatment with FP and to verify if its distribution was compatible with the prevalence of partial DPD deficiency estimated in the Caucasian population. Material and methods: prospective observational study in which cancer patients candidates for FP treatment were included. For the analytical determination, a Dionex Ultimate 3000 UHPLC system coupled to a Q-exactive hybrid quadrupole-orbitrap mass spectrometer was used. Results: 77 patients, with a mean age of 71 years, were included. The mean and median serum U concentrations were 30.4 and 24.0 ng/ml, respectively. The range was from 7.1 to 139.7 ng/ml. 79.2% of the patients presented a U level between 16 and 150ng/ml, showing a statistically significant difference when compared to the estimated prevalence in the Caucasian population (8%) (p-value <0.0001). The analytical method used has a correlation coefficient R2 > 0.99 and a detection limit <0.2 ng/ml. Conclusions: it is necessary to carry out more studies with a design aimed at establishing the optimal conditions related to the pretreatment of the samples in order to avoid or minimize the influence of these factors on the analyte values. (AU)

Evaluation of the pretransplantation phase of the hemopoietic stem cell program in a tertiary hospital.

INTRODUCTION: Therapeutic decisions and clinical events during the pretransplantation phase of stem cell transplantation (SCT) may influence survival, quality of life, and efficiency of health expenses. However, there is a lack of relevant published data. AIMS: The aims of this study were to identify reasons why the procedure was not performed and to know the waiting time for SCT candidates. PATIENTS AND METHODS: We collected pretransplantation data from 166 consecutive patients evaluated by the SCT Committee of a tertiary center between April 2005 and December 2006. RESULTS: One hundred fifty-two of 166 patients were referred for the first time. Additionally, 14 were reconsidered as candidates for a subsequent SCT due to relapse, graft failure, secondary malignancy, or a multiple-graft program. One hundred forty-one were accepted for transplantation, whereas 25 were not. At the time of analysis, 22 patients were still awaiting SCT, 8 were delayed because they required additional courses of treatment, and 32 were excluded because of death (34.4%), poor stem cell mobilization (21.9%), patient refusal (15.6%), relapse/progression (9.4%), comorbidity (6.3%), or absence of a donor (6.3%). The median time between inclusion in the program and transplantation was 3.6 months (range, 0.27-13.43), and 5.7 months (P < .05) for unrelated allogeneic transplantation. No significant differences were observed in the diagnosis or hospital of origin. CONCLUSIONS: SCT was not performed in 22% of transplant candidates, mainly due to death, insufficient stem cell mobilization, patient refusal, or disease progression/relapse. The median time between inclusion in the SCT program and transplantation was 3 months, but longer among the unrelated allogeneic transplantations.

La hepatitis crónica y su diagnóstico precoz / Chronic hepatitis and its early diagnosis

Se exponen y analizan los resultados obtenidos en el estudio de 119 pacientes a quienes se les diagnosticó hepatitis crónica, a trevés del cuadro clínico, humoral, laparoscópico e hístico, evidenciándose que el 62 porciento de los casos habían sido catalogados presuntivamente como supuestas hepatitis virales. Se encontró que el mayor porcentaje de casos tenían entre 15 y 24 años, y los síntomas más frecuentes son la astenia, anorexia y el dolor en hipocondrio derecho, y la hepatomegalia el signo más constante. La transaminasa glutámico-pirúvica fue de poca utilidad en aquellos pacientes anictéricos. Por último se insiste en la importancia que adquiere la laparoscopia y la biopsia hepática en el diagnóstico temprano de esta entidad(AU)

Hepatitis crónica persistente. Evolución / Persistentchronic hepatitis. Its course

Se presenta un trabajo sobre la evolución de 76 pacientes a quienes se diagnosticó hepatitis crónica persistente, a través del estudio clínico, humoral, laparoscópico e hístico en períodos comprendidos entre 6 meses y 5 años. Se obtiene una evolución satisfactoria en la generalidad de los casos con 9 pacientes que mostraron mejoría hística y 7 cuadro hístico sin alteraciones evolutivamente. Los síntomas que con más frecuencia persistieron fueron las astenias y el dolor del hipocondrio derecho. Se señala cómo aquellos pacientes que presentaron un síndrome ictérico inicialmente, mostraron una evolución clínico-humoral similar a la de la hepatitis viral aguda(AU)

Patología tumoral de la mama. Revisión de 25, 000 biopsias en los hospitales militares "Carlos J. Finlay" y "Luis Díaz Soto". Trabajo estadístico / Tumoral pathology of the breast. A revision of 25, 000 biopsies from "Carlos J. Finlay" and "Luis Díaz Soto" hospital. Statistical study

En la revisión efectuada en las 25, 000 biopsias correspondieron a la patología mamaria 493 para un 1,97 porciento del total. Del Hospital "Carlos J. Finlay" se revisaron 23, 000 correspondiendo 448 a la mama para un 1,94 porciento del total de este hospital y 2, 000 del Hospital Militar Central de las F.A.R. "Luis Díaz Soto", correspondiendo a la mama 45 para un porcentaje de 2,25 porciento del total de este hospital. El 14,42 porciento del total de biopsias mamarias correspondieron al sexo masculino y todas las diagnosticaron como ginecomastias. Del total del Hospital Díaz Soto, el 33, 33 porciento correspondió a dicha entidad. Esto se debe al tipo de predominio en los jóvenes del sexo masculino atendidos en este hospital. Al cáncer de la mama correspondió un 15, 2 porciento del total de biopsias estudiadas. El resto de los porcentajes coinciden en términos generales con otras estadísticas revisadas (AU)