22 research outputs found

    Preliminary immunohistochemical investigations of thyroid C cells in an experimental model of hyperthyroidism

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    The role of the parafollicular (C) cells, the second most important cells in the thyroid gland, has not hitherto been clarified. They are considered to be disperse neuroendocrine cells of the APUD system and synthesise and release many of the regulatory peptides. Few publications are concerned with the evaluation of the structure and function of C cells in the thyroid gland or the probable relationship between these cells and the follicular cells in physiological and pathological conditions. For this reason immunohistochemical investigations were carried out into the activity of the C cells in rats in an experimental model of hyperthyroidism caused by chronic thyroxine influence. This C-cell activity was then evaluated. Differences in the quantity, distribution and calcitonin immunoreactivity of C cells were observed in hyperthyroid rats in comparison to the control group, together with a significant diminution of plasma TSH and calcitonin levels. Our preliminary study may indicate a functional interaction between follicular and parafollicular cells in the thyroid gland

    An immunohistochemical study of the thyroid parafollicular (C) cells in rats treated with cannabinoids - preliminary investigations

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    The purpose of the present study was to evaluate the effect of a single intraperitoneal injection of a stable analogue of endogenous cannabinoid anandamide - R-(+)-methanandamide (2.5 mg/kg) and CP 55,940 (0.25 mg/kg), an egzogenous CB1 receptor-agonist, on the calcitonin (CT) immunoreactivity of the thyroid parafollicular (C) cells. Four hours after injection with both cannabinoids CT immunoreactivity, evaluated with an avidin-biotin peroxidase complex method by means of rabbit antibodies against CT, was seen to be enhanced in the parafollicular cells in comparison to those of the control group. In thyroids taken from cannabinoid-treated rats the majority of follicles, particularly those located peripherally were large in size, and had low epithelium. Moreover, dilatation of the blood vessels was observed. These changes were accompanied by a significant decrease in CT plasma level, without changes in calcium concentrations. This is the first evidence that a single injection of the cannabinoids R-(+)-methanandamide and CP 55,940 significantly decreases the activity of thyroid C cells

    CCN1 expression in interleukin-6 deficient mouse kidney in experimental model of heart failure

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    Chronic heart failure often leads to worsening of the renal function. Mediators of this process include inflammatory and neuroendocrine factors. CCN1 (Cyr 61), a member of growth factor-inducible immediate early genes, which modulates inflammation and fibrogenesis, is excreted with urine in the early phase of acute renal injury and may be involved in the pathogenesis of the cardiorenal syndrome. The aim of the study was to evaluate CCN1 protein abundance and localization in the kidney of IL-6-deficient C57BL/6J (IL-6 KO) mice and respective wild-type (WT) animals in basal conditions and in animals with chronic heart failure twelve weeks after myocardial infarction. Age- and sex-matched mice from both strains subjected to sham operation served as controls. One group of WT animals subjected to myocardial infarction was treated with antagonist of AT1 receptor telmisartan over 12 weeks. Abundance and localization of CCN1 protein in kidney were assessed with Western blotting and immunohistochemistry, respectively. In all groups the strongest immunohistochemical reaction for CCN1 was observed in distal convoluted tubules and in smaller arteries, however, the total expression of CCN1 protein was lower in IL-6 KO mice in comparison to WT animals. The main difference in CCN1 distribution between the examined genotypes was lack of reaction in internal renal medulla and very weak reaction in proximal convoluted tubules in IL-6 KO mice. Experimental heart failure only slightly attenuated the expression of CCN1 protein in the kidney of WT mice and had no effect in IL-6 KO mice. Although, blockade of AT1 receptor did not alter CCN1 protein expression in kidneys of WT mice after myocardial infarction, it significantly changed its CCN1 distribution in the renal tubular system. (Folia Histochemica et Cytobiologica 2013, Vol. 51, No. 1, 84–91

    Germinal epimutation of Fragile Histidine Triad (FHIT) gene is associated with progression to acute and chronic adult T-cell leukemia diseases

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    Background: Human T cell Leukemia virus type 1 (HTLV-I) is etiologically linked to adult T cell leukemia/lymphoma (ATL) and an inflammatory neurodegenerative disease called HTLV-I-associated myelopathy or tropical spastic paraparesis (HAM/TSP). The exact genetic or epigenetic events and/or environmental factors that influence the development of ATL, or HAM/TSP diseases are largely unknown. The tumor suppressor gene, Fragile Histidine Triad Diadenosine Triphosphatase (FHIT), is frequently lost in cancer through epigenetic modifications and/or deletion. FHIT is a tumor suppressor acting as genome caretaker by regulating cellular DNA repair. Indeed, FHIT loss leads to replicative stress and accumulation of double DNA strand breaks. Therefore, loss of FHIT expression plays a key role in cellular transformation. Methods: Here, we studied over 400 samples from HTLV-I-infected individuals with ATL, TSP/HAM, or asymptomatic carriers (AC) for FHIT loss and expression. We examined the epigenetic status of FHIT through methylation specific PCR and bisulfite sequencing; and correlated these results to FHIT expression in patient samples. Results: We found that epigenetic alteration of FHIT is specifically found in chronic and acute ATL but is absent in asymptomatic HTLV-I carriers and TSP/HAM patients' samples. Furthermore, the extent of FHIT methylation in ATL patients was quantitatively comparable in virus-infected and virus non-infected cells. We also found that longitudinal HTLV-I carriers that progressed to smoldering ATL and descendants of ATL patients harbor FHIT methylation. Conclusions: These results suggest that germinal epigenetic mutation of FHIT represents a preexisting mark predisposing to the development of ATL diseases. These findings have important clinical implications as patients with acute ATL are rarely cured. Our study suggests an alternative strategy to the current "wait and see approach" in that early screening of HTLV-I-infected individuals for germinal epimutation of FHIT and early treatment may offer significant clinical benefits

    Anticipating policy considerations for a future HIV vaccine: a preliminary study

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    4siNew human immunodeficiency virus (HIV) infections continue to occur worldwide. Despite previous failures, there is renewed optimism about developing an efficacious HIV prophylactic vaccine following the 31.2% vaccine efficacy (modified intention to treat analysis) achieved in the RV-144 trial. Intense efforts at characterising the immune responses in the trial participants who appeared to gain some protection from the candidate vaccine are ongoing to delineate correlates of protection. However, the characteristics of a vaccine suitable for programmatic introduction in high prevalence areas remain undefined.nonemixedWilliams, Emmanuel Ato; Lewis, David J M; Bertholet, Sylvie; Zazzi, MaurizioWilliams, Emmanuel Ato; Lewis, David J. M; Bertholet, Sylvie; Zazzi, Maurizi
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