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51.
BACKGROUND: Hemophagocytic histiocytosis (HPS) is an idiopathic, familial or secondary syndrome characterized by mature histiocytes causing intensive erythrophagocytosis. CASE: A 2-month-old male suffering from autoimmune hemolytic anemia, fever, jaundice and hepatosplenomegalia underwent fine needle aspiration cytology of the spleen. Aspiration was performed using a 23-gauge, short needle with a subcostal approach. The smear showed a monomorphous cell population of mature histiocytes with marginal nuclei and wide, well-defined cytoplasm. The cytoplasm was microvaculated and often contained > or = 1 erythrocytes and occasional lymphocytes. Immunostaining performed on cytospin samples showed diffuse positivity for alpha-1-antichymotrypsin and S-100. Differential diagnosis with malignant histiocytosis, Langerhans histiocytosis and sinus histiocytosis with massive lymphadenopathy was established. HPS was diagnosed because of the cytologic and immunocytochemical features and clinical data. CONCLUSION: HPS may be diagnosed using fine needle aspiration of the spleen when other biopsy samples have been unsuccessful. Cytologic, diagnosis of HPS should always be considered in a specific clinical setting, because early treatment can often save the patient's life.  相似文献   
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Heavy metals, depending on their oxidation states, can be highly reactive and, as a consequence, toxic to most organisms. They are produced by an expanding variety of anthropogenic sources suggesting an increasingly important role for this form of pollution. The toxic effect of heavy metals appears to be related to production of reactive oxygen species (ROS) and the resulting unbalanced cellular redox status. Algae respond to heavy metals by induction of several antioxidants, including diverse enzymes such as superoxide dismutase, catalase, glutathione peroxidase and ascorbate peroxidase, and the synthesis of low molecular weight compounds such as carotenoids and glutathione. At high, or acute, levels of metal pollutants, damage to algal cells occurs because ROS levels exceed the capacity of the cell to cope. At lower, or chronic, levels algae accumulate heavy metals and can pass them on to organisms of other trophic levels such as mollusks, crustaceans, and fishes. We review here the evidence linking metal accumulation, cellular toxicity, and the generation of ROS in aquatic environments.  相似文献   
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4-Deoxypyridoxine (4-DPD) is a potent antagonist of Vitamin B6 coenzyme which inhibits IL-1, lymphocyte proliferation and has demonstrated that tollerance to skin grafts can be induced by administering splenic cells to pyridoxine-deficient mice. Chronic inflammation induced by dorsal injections of 200 l of a 140 saturated crystal solution of potassium permanganate (KMnO4) in mice treated or untreated with 4-DPD (400 g/dose), has been investigated. After 7 days all mice developed a subcutaneous granulomatous tissue indicative of a chronic inflammatory response, at the site of injection. KMnO4-treated mice injected intraperitoneally with 4-DPD (400 g/dose) on 5 consecutive days (the first at the same time of induction of the granuloma) show a significant decrease in size and weight of granuloma when compared to mice not treated with 4-DPD (Controls). In addition, in all mice treated with 4-DPD there was a strong inhibition of TNF in serum (P<0.01) and in supernatant fluids (P<0.05) from minced granuloma, while IL-6 was inhibited in the supernatant fluids (P<0.05) of minced granulomas but was not detected in the serum of treated and untreated mice. In this study we show for the first time the antiinflammatory effect of 4-DPD on chronic inflammation and the inhibitory effect of TNF and IL-6 generation in supernatant fluids from minced granulomas.  相似文献   
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The 2016 World Health Organisation revised classification of lymphoma has sub‐classified well‐defined entities and added a number of provisional entities on the basis of new knowledge on genetic, epigenetics and phenotypical data; prognostic and predictive features are also part of this classification. New knowledge on well‐defined entities further enlightens the mechanisms of lymphomagenesis, which are more complex and multifactorial than once believed. Therapies are also more complex because traditional clinical trials have been integrated with new drugs and compounds with unique mechanisms of actions against distinct molecular targets. As lymphoma acquires additional genetic and phenotypic features over the time, pathological assessment is also necessary. Histological evaluation and tissue collection by surgical biopsies are necessary for phenotypical and molecular purposes; however, these are demanding procedures for both the patient and the health care system. At the same time, the choice of the best treatment for a specific entity, in different phases and different patients requires information that may not be available when the biopsy is performed. Fine needle aspiration cytology (FNAC) is successfully used in lymph nodes (LNs) in combination with different ancillary techniques and might be used to assess the phenotypic and genetic profile of specific targets and to get key information for therapy, in different phases and stages of the disease, with the option to re‐check the same target over time, without surgical excision. This brief review describes LN‐FNAC diagnostic criteria, current therapies for lymphomas and the potential role of LN‐FNAC in selecting non‐Hodgkin lymphomas patients for specific targeted treatments.  相似文献   
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