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51.
A case of intestinal anisakiasis caused by Anisakis sp. larva type I in a woman from Italy who consumed raw marinated anchovies, is reported. The diagnosis was based on the morphological features characteristic of anisakid larval stages, which were readily recognized in a large granuloma removed after emergency surgical treatment.  相似文献   
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Colorectal cancer has provided an important model to test the stem cell hypothesis of cancer origin, which implies that cancer arises as a result of genetic aberrations in stem cells leading to deregulation of the proliferation/differentiation balance. We and others have demonstrated that, similarly to other solid tumors, colon carcinogenesis and progression are dictated by highly apoptosis‐resistant stem‐like cells. Our data have suggested that protection from apoptosis is achieved by autocrine production of interleukin‐4 (IL‐4) through up‐regulation of anti‐apoptotic mediators. In this study, we extend our analysis to another apoptosis inhibitor widely expressed in tumors, namely survivin (also known as BIRC‐5, baculoviral IAP repeat‐containing protein 5). We show that this protein, with important roles in cell death counteraction and mitotic progression control, is regulated by the IL‐4 pathway in colon rectal cancer stem cells (CR‐CSC). Hence, the presence of IL‐4 increases survivin levels in our model while cytokine neutralization has opposing effects. Treatment with cytokine neutralizing agent or with leflunomide, Stat6 inhibitor, have similar consequences on survivin localization, increasing its nuclear pool, an observation known to be correlated with a good prognosis in colon cancer patients. These results demonstrate that IL‐4, through activation of the STAT‐6 signaling pathway, is involved in survivin expression levels as well as its localization. These findings shed more light on the molecular mechanisms involved in IL‐4‐mediated chemoresistance. J. Cell. Physiol. 225: 555–561, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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Male Wistar rats chronically (15 weeks) fed a sucrose-rich diet (SRD; 63% w/w) developed hypertriglyceridemia and impaired glucose homeostasis. Hearts from these animals were isolated and perfused using the Langendorff recirculating method. Glucose at levels similar to those found in the animal in vivo was used as the only exogenous substrate. The hearts were perfused for 30 minutes in the presence or absence of insulin (30 mU/mL) in the perfusion medium. In the absence of the hormone, glucose uptake was impaired and the glucose utilization was reduced, with a significant increase of lactate release. Glucose oxidation, which was estimated from the activation state of the enzyme pyruvate dehydrogenase complex (PDHc), was depressed mainly due to both an increase of PDH kinase and a decrease of PDHa (active form of PDHc) activities. Although the addition of insulin in the perfusion medium improved the above parameters, it was unable to normalize them. The present results suggest that at least two different mechanisms might contribute to insulin resistance and to the impaired glucose metabolism in the perfused hearts of the dyslipemic SRD-fed animals: (1) reduced basal and insulin-stimulated glucose uptake and its utilization or (2) increased availability and oxidation of lipids (low PDHa and high PDH kinase activities), which in turn decrease glucose uptake and utilization. Thus, this nutritional experimental model may be useful to study how impaired glucose homeostasis, increases plasma free fatty acid levels and hypertriglyceridemia could contribute to heart tissue malfunction.  相似文献   
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The integrity of sperm chromatin is now viewed as an important factor in male fertility and in early embryonic development. The objectives of this study were: (1) adapt the simple and inexpensive sperm chromatin dispersion (SCD) test to evaluate DNA fragmentation in llama sperm and establish the halo patterns observed in this species, (2) determine an effective and reliable positive control for this technique and (3) evaluate correlation between the SCD test and the toluidine blue (TB) stain. To adapt the SCD test, three different mercaptoethanol (ME) concentrations were assayed (2.5%, 5% and 10% ME). To determine an effective positive control, three treatments (incubation at 100 °C for 30 min, incubation with 0.3 M NaOH for 30 min at room temperature and exposure to UV light for 2h) were assayed. The concentration selected to use in the SCD test was 5% ME, because it produced the largest halo while still conserving the structure of the core. Four DNA dispersion patterns were clearly observed: (I) nuclei with large DNA dispersion halos; (II) nuclei with medium halos; (III) nuclei with very small halos and (IV) nuclei with no halo. All treatments used as positive controls were effective in producing DNA fragmentation. A high correlation (r=0.84, P=0.03) was observed between spermatozoa without halos and TB positive cells. To conclude, SCD patterns in llama sperm have been established as well as a repeatable positive control for the assay. The SCD test and TB stain are simple and inexpensive techniques that can be used to evaluate DNA damage in llama sperm.  相似文献   
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Highlights? Immunomodulatory properties of MSCs in vitro and in vivo are discussed. ? Safety and efficacy of treatments with allogeneic MSCs are discussed. ? Future directions to improve efficacy of MSC treatments are proposed.  相似文献   
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A series of phenylacylsulfonamides has been prepared as antagonists of Bcl-2/Bcl-xL. In addition to potent binding affinities for both Bcl-2 and Bcl-xL, these compounds were shown to induce classical markers of apoptosis in isolated mitochondria. Overall weak cellular potency was improved by the incorporation of polar functionality resulting in compounds with moderate antiproliferative activity.  相似文献   
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5-Butyl-1,4-diphenyl pyrazole and 2-amino-5-chloro pyrimidine acylsulfonamides were developed as potent dual antagonists of Bcl-2 and Bcl-xL. Compounds were optimized for binding to the I88, L92, I95, and F99 pockets normally occupied by pro-apoptotic protein Bim. An X-ray crystal structure confirmed the proposed binding mode. Observation of cytochrome c release from isolated mitochondria in MV-411 cells provides further evidence of target inhibition. Compounds demonstrated submicromolar antiproliferative activity in Bcl-2/Bcl-xL dependent cell lines.  相似文献   
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