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El cáncer papilar de tiroides (CPT) tiene diferentes variantes y la mayoría de ellas presentan diferencias sutiles. La variante oncocítica (VO) es un subtipo poco frecuente de CPT, sobre el pronóstico de la cual existen resultados controvertidos en la literatura. Investigamos su agresividad y curso clínico comparándolos con la variante clásica (VC) y la variante de células altas (CA) de CPT en diferentes estadios. En este estudio de cohortes retrospectivo se incluyeron: 100 muestras simples de VO, 71 de CA y 1.219 de VC. Las muestras VO se compararon con las VC y las de CA sobre la base de parámetros de pronóstico independientes. La recurrencia de la VO también se comparó estadio por estadio con la VC y CA. La edad media fue de 46,8 años y la relación hombres/mujeres de 25/75 para la VO. Las tasas de recurrencia en nuestro estudio fueron del 16% en VO; del 13,5% en VC y del 56% en CA. Existe una diferencia estadísticamente significativa con respecto a la recurrencia entre el estadio 1 y el estadio 4 comparando la VO y la VC (p = 0,023; p = 0,03, respectivamente). También hay una diferencia estadísticamente significativa con respecto a la recurrencia entre el estadio 1 y el estadio 4 comparando la VO y la CA (p = 0,001; p = 0,024, respectivamente). Se puede suponer que la VO tiene un comportamiento entre la VC y la CA, pero muy cercana a la CA. La VO parece ser un poco más agresiva que la VC. A pesar de un tamaño de muestra inadecuado para los estadios 2 y 3, nuestros hallazgos implican un mayor riesgo de recurrencia para la VO que para la VC en los estadios avanzados (estadios 3 y 4) y la VC tiene un pronóstico más desfavorable que VO en estadios precoces (estadios 1 y 2), según el modelo de estadio pareado. Papillary thyroid cancer (PTC) has many variants and most of them are mild tumors. Oncocytic variant (OV) is a rare subtype of PTC. There are controversial results about its prognosis in the literature. We investigated its aggressivity and clinical course by comparing it with classical variant (CV) and tall cell variant (TV) of PTC over a stage-matched design. Pure 100 OV, 71 TV and 1,219 CV were included in this retrospective cohort study. OV was compared with CV and TV according to independent prognostic parameters. OV was also compared stage by stage with CV and TV for recurrence. Mean age was 46,8 years and male/female ratio 25/75 for OV. The recurrence rates in our study were 16% in OV, 13,5% in CV and 56% in TV. There is a statistically significant difference according to recurrence between stage 1 and stage 4 OV and CV (P = 0.023, P = 0.03, respectively). There is also a statistically significant difference between stage 1 and stage 4 OV and TV according to recurrence (P = 0.001, P = 0.024, respectively). OV can be supposed to behave between CV and TV, but very closer to CV. OV seems to be slightly more aggressive than CV. Despite an inadequate sample size for stage 2 and 3, our findings imply an increased recurrence risk for OV than CV at the advanced stages (stage 3 and 4) and CV has an unfavorable prognosis than OV at early stages (stage 1 and 2) according to stage-matched model. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to establish three-dimensional cultures originating from muscle biopsies and evaluate the viability and morphology. Method: Muscle biopsies from patients with suspected neuromuscular disorders were obtained and established as primary muscle tissue cultures. Tissue pieces, 1–2 mm of diameters, were placed in culture medium and subjected to sporadic stirring to prevent attachment and outgrowth as monolayer cells. Morphology and ability to attach to the surface were investigated by light microscopy. Viability was evaluated by 99mTc-tetrofosmin uptake. After 1 month, histology was evaluated by light microscopy and immunocytochemistry. The findings of a healthy muscle and a dystrophic muscle were compared. Results: Initially, the tissue pieces were unshaped but formed spheroid-like structures during the culture period. For dystrophic muscle, attachment capacity to the surface was initially potent and decreased during the culture period, whereas control muscle showed weak attachment from the start that increased during the culture period. The uptake of 99mTc-tetrofosmin increased in control muscle, while it decreased in dystrophic muscle, during the culture period. The histological investigation demonstrated larger destruction of myofiber, weaker satellite cell activation and reduced myofiber regeneration in the dystrophic muscle as compared to the control muscle. Conclusion: The cellular components of the muscle tissue can survive and proliferate as spheroid-like primary cultures. The cellular composition resembles the in vivo condition, which allows studies of degeneration of the original fibers, and activation and proliferation of the satellite cells. The culture system may provide better understanding of the degeneration and regeneration processes in different muscle disorders and allow investigations of pharmacological interventions. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to elucidate the mechanisms of action for potential targets of therapeutic intervention related to the arachidonic acid cascade in muscular dystrophy. Primary cultures from a Duchenne patient were used to study the expression of dystrophin-1, utrophin, desmin, neonatal myosin heavy chain (MHCn) and Bcl-2 during inhibition of phospholipase A2 (PLA2), cyclooxygenase (COX) and lipoxygenase (LOX). Hypo-osmotic treatment was applied in order to trigger Ca2+ influx and PLA2 activity. Inhibition of PLA2 and LOX with prednisolone and nordihydroguaiaretic acid (NDGA) caused a semi-quantitative increase of utrophin and Bcl-2-, and a dose-dependent, quantitative increase of desmin expression, an effect that was augmented by hypo-osmotic treatment. Our results indicate that LOX inhibitors, similarly to corticosteroids, can be beneficial in the treatment of muscular dystrophies. [Copyright &y& Elsevier]

Purpose: Glutathione is an important cellular compound which affects detoxification of electrophiles and may have direct or indirect effects on pigment formation. It is therefore of importance to study interstitial concentrations in melanoma tissue while decreasing its formation with an enzyme inhibitor and increasing its amount with cysteine deliverers.Method: Glutathione formation was inhibited by intraperitoneal (i.p.) injection of BSO. N-Acetylcysteine (NAC) and l-2-oxothiazolidine-4-carboxylate (OTC) were then given i.p. to subgroups of the animals. Intratumoral microdialysis was performed during BSO treatment, during BSO treatment combined with NAC or OTC and after discontinuation of BSO but ongoing NAC or OTC treatment.Results: Glutathione formation was inhibited during BSO treatment. The dialysate concentrations of both glutathione and cysteine decreased during concomitant treatment with BSO and NAC or OTC. Recovery of the amounts of the two compounds was seen in both groups after discontinuation of BSO treatment. In the NAC group we also observed an acute increase in dialysate concentrations of cysteine after NAC injection. The 5-S-cysteinyldopa concentrations were unaffected by variations in glutathione and cysteine concentrations.Conclusions: 5-S-Cysteinyldopa in melanoma is not formed from glutathione in vivo to any appreciable extent. The intracellular amount of cysteine is probably not a limiting factor for cysteinyldopa formation. It seems that both NAC and OTC can be used as cysteine deliverers to melanoma cells in vivo to produce recovery of glutathione levels after synthesis inhibition by BSO treatment. [ABSTRACT FROM AUTHOR]