ABSTRACT Objective: It is agreed that methimazole (MMI) can be administered to induce hypothyroidism. However, there are conflicting data about its effect on thyroid function and development in rats through different administrations. In the present study, we established and compared differences of the rat hypothyroid model induced by MMI added to drinking water or given through an intragastric tube. Methods: Sixty-four male Wistar rats were randomly divided into seven groups. Methimazole was added to the drinking water (0.025%, 0.04% or 0.1% wt/vol), or through intragastric gavage (5 mg/100 g body weight (bw) or 8 mg/100 g bw) one time each day for 21 days. The rats were weighed every seven days. Blood samples were taken in order to detect the concentrations of serum triiodothyronine (T3), thyroxine (T4) and thyrotropin (TSH) at the end of the experiments. Results: Our results indicate that the effect of methimazole on a rat's thyroid function and body weight is similar in both the group given 0.1% concentration in drinking water and the group which received 8 mg/100 g bw once daily through the intragastric tube. Also, a similar effect was observed in the 0.025%, 0.04% and 5 mg/100 g bw groups. Conclusion: These findings suggest that a relationship between the concentration of MMI by oral administration and the dose of it through intragastric administration could exist, and may contribute to inducing hypothyroidism in rats.

RESUMEN Objetivo: Existe acuerdo en cuando a que el metimazol (MMI) puede ser administrado para inducir hipotiroidismo. Sin embargo, hay datos contradictorios en relación con su efecto sobre la función tiroidea y el desarrollo en ratas a través de diferentes administraciones. En el estudio actual, establecimos y comparamos las diferencias del modelo de hipotiroidismo en ratas. El hipotiroidismo es inducido añadiendo MMI al agua de beber, o suministrándolo a través de un tubo intragástrico. Métodos: Sesenta y cuatro ratas Wistar machos fueron divididas aleatoriamente en siete grupos. El metimazol fue añadido al agua de beber (0.025%, 0,04% ó 0.1% p/v), o suministrado mediante sonda intragástrica (5 mg/100 g de peso corporal (pc) ó 8 mg/100 g pc) una vez cada día por 21 días. Las ratas se pesaron cada 7 días. Se tomaron muestras de sangre para detectar las concentraciones de triyodotironina (T3), tiroxina (T4) y tirotropina (TSH) en suero al final de los experimentos. Resultados: Nuestros resultados indican que el efecto del metimazol sobre la función de la tiroides y el peso corporal de una rata es similar tanto en el grupo que recibió una concentración de 0.1% en el agua de beber como en el grupo que recibió 8 mg/100 g pc una vez al día a través de un tubo intragástrico. También se observó un efecto similar en los grupos de 0.025%, 0.04% y 5 mg/100 g pc. Conclusión: Estos resultados sugieren que podría existir una relación entre la concentración de MMI mediante administración oral y la dosis de la misma a través de administración intragástrica, lo cual puede contribuir a inducir hipotiroidismo en ratas.

This study aimed to explore the correlations between cadherin-17 (CDH17) protein expression and the clinicopathological features and prognosis of patients with sporadic gastric cancer (GC). Nine relevant studies of 1,960 patients were identified using electronic database searches supplemented with a manual search in strict accordance with inclusion and exclusion criteria. Statistical analyses were conducted using STATA 12.0 statistical software. Relative risks and 95% confidence intervals were determined, and Z test was used to measure the significance of the overall effect size. A total of nine eligible cohort studies were included in this meta-analysis. The expression of CDH17 in patients with diffuse GC was significantly higher than in those with intestinal-type GC. Moreover, the tumor depth of invasion differed significantly between patients with positive CDH17 (CDH17+) and negative CDH17 (CDH17-) GC. However, there were no significant differences between CDH17+ and CDH17- GC patients with respect to tumor node metastasis clinical stages, histological grades, or lymph node metastasis. Despite the differences in invasive depth, there was no significant difference in 5-year survival rates between CDH17+ and CDH17- GC patients. Our meta-analysis provides evidence that CDH17 protein expression may be associated with the development of GC, suggesting that CDH17 is an important biomarker that could be useful for the early diagnosis of GC. However, CDH17 levels do not appear to impact overall survival.

Agaricus blazei Murill is a native Brazilian mushroom which functions primarily as an anticancer substance in transplanted mouse tumors. However, the mechanism underlying this function of A. blazei Murill remains obscure. The present study was carried out to investigate the effect of fraction FA-2-b-ß, an RNA-protein complex isolated from A. blazei Murill, on human leukemia HL-60 cells in vitro. Typical apoptotic characteristics were determined by morphological methods using DNA agarose gel electrophoresis and flow cytometry. The growth suppressive effect of fraction FA-2-b-ß on HL-60 cells in vitro occurred in a dose- (5-80 µg/mL) and time-dependent (24-96 h) manner. The proliferation of HL-60 cells (1 x 10(5) cells/mL) treated with 40 µg/mL of fraction FA-2-b-ß for 24-96 h and with 5-80 µg/mL for 96 h resulted in inhibitory rates ranging from 8 to 54.5%, and from 4.9 to 86.3%, respectively. Both telomerase activity determined by TRAP-ELISA and mRNA expression of the caspase-3 gene detected by RT-PCR were increased in HL-60 cells during fraction FA-2-b-ß treatment. The rate of apoptosis correlated negatively with the decrease of telomerase activity (r = 0.926, P < 0.05), but correlated positively with caspase-3 mRNA expression (r = 0.926, P < 0.05). These data show that fraction FA-2-b-ß can induce HL-60 cell apoptosis and that the combined effect of down-regulation of telomerase activity and up-regulation of mRNA expression of the caspase-3 gene could be the primary mechanism of induction of apoptosis. These findings provide strong evidence that fraction FA-2-b-ß could be of interest for the clinical treatment of acute leukemia.