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Corn samples were collected in 1999 from three departments of Entre Réos province, Argentina, and were surveyed for mould contamination and natural occurrence ofFusarium mycotoxins, ochratoxin A and aflatoxins.Fusarium verticillioides was the most prevalent fungal species recorded at all departments. Zearalenone, deoxynivalenol and ochratoxin A were not found in any samples. Only one of the 52 corn samples analysed was contaminated with aflatoxin B1 (17 μg/kg). Fumonisin B1 was found in 58 % of samples (range of positive samples: 47– 3,347 μg/kg), fumonisin B2 in 33.0 % (range of positive samples: 23–537 μg/kg) and fumonisin B3 in 25.0 % (range of positive samples: 24–287 μg/kg) of them. This is the first report on the natural occurrence of mycotoxins in corn from Entre Ríos province, Argentina. Levels of fumonisins were lower than detected in other Argentinian provinces.  相似文献   
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Head and neck squamous cell carcinoma (HNSCC) is known to cause substantial immunosuppression. The present study was designed to characterize blood leukocyte activation in HNSCC and to investigate if the individual activation pattern could be related to tumor progress and survival. The leukocyte activation profile of HNSCC patients and healthy controls was assessed with flow cytometry. HNSCC patients displayed increased numbers of monocytes, neutrophils and total leukocytes as well as an enhanced neutrophil/lymphocyte ratio. In addition, patients had a higher percentage of CD69+, CD71+ and CD98+ T cell subsets and NK cells, and a reduced expression of L-selectin in CD14highCD16+ monocytes and neutrophils, when compared to controls. These changes could be correlated to both tumor burden and spread to lymph nodes. Among the cancer patients an increased neutrophil/lymphocyte ratio, a low neutrophil and CD14high CD16+ monocyte activation state and an elevated CD4/CD8 ratio were related to poor survival. In contrast, a high percentage of CD98+ Th cells appeared to be associated with a better outcome. Taken together, the present data indicate that HNSCC causes activation of blood leukocytes and that the individual activation pattern can be linked to prognosis.  相似文献   
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Glycogen levels, glycogen synthase activities, and glycogen synthase protein levels were determined in liver tissues obtained from 14- to 19-day-old fetal mice, newborn mice, and adult mice. The results of these experiments demonstrate a significant increase in the quantity of hepatic glycogen synthase beginning at Day 17 of gestation and reaching adult levels at birth. However, during the same time period, there is a dramatic decrease in total glycogen synthase activity suggesting that the accumulating glycogen synthase molecules are unable to transfer UDP-glucose to glycogen. These inversely coordinated changes in the quantity and activity of glycogen synthase are consistent with the suggestion that glycogen synthesis in the near-term fetal mouse is being maintained by preexisting enzyme, while accumulating enzyme molecules may represent a quiescent isozyme.  相似文献   
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Background

The origin of nasal polyps in chronic rhinosinusitis is unknown, but the role of viral infections in polyp growth is clinically well established. Toll-like receptors (TLRs) have recently emerged as key players in our local airway defense against microbes. Among these, TLR9 has gained special interest in viral diseases. Many studies on chronic rhinosinusitis with nasal polyps (CRSwNP) compare polyp tissue with nasal mucosa from polyp-free individuals. Knowledge about changes in the turbinate tissue bordering the polyp tissue is limited.

Objectives

To analyse the role of TLR9 mediated microbial defense in tissue bordering the polyp.

Methods

Nasal polyps and turbinate tissue from 11 patients with CRSwNP and turbinate tissue from 11 healthy controls in total were used. Five biopsies from either group were analysed immediately with flow cytometry regarding receptor expression and 6 biopsies were used for in vitro stimulation with a TLR9 agonist, CpG. Cytokine release was analysed using Luminex. Eight patients with CRSwNP in total were intranasally challenged with CpG/placebo 24 hours before surgery and the biopsies were collected and analysed as above.

Results

TLR9 expression was detected on turbinate epithelial cells from healthy controls and polyp epithelial cells from patients, whereas TLR9 was absent in turbinate epithelial cells from patients. CpG stimulation increased the percentage cells expressing TLR9 and decreased percentage cells expressing VEGFR2 in turbinate tissue from patients. After CpG stimulation the elevated levels of IL-6, G-CSF and MIP-1β in the turbinate tissue from patients were reduced towards the levels demonstrated in healthy controls.

Conclusion

Defects in the TLR9 mediated microbial defense in the mucosa adjacent to the anatomic origin of the polyp might explain virus induced polyp growth. CpG stimulation decreased VEGFR2, suggesting a role for CpG in polyp formation. The focus on turbinate tissue in patients with CRSwNP opens new perspectives in CRSwNP-research.  相似文献   
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