Sterigmatocystin (STG) is a toxic metabolite produced by severalAspergillus species. Because of its toxic and carcinogenic properties the occurrence of STG in food is considered to represent a potential
hazard to man. The present study was designed to investigate following points:
1
A survey of STG incidence in Ras cheese on local markets. Ras cheese samples were collected from Cairo, Giza and Kalubia
governorates. Thirty five percent of the samples contained the toxin with a mean value of 22.23 μg /kg
2
Fate of STG contaminating milk during Ras cheese processing. Milk was artificially contaminated with 125 μg/kg and processed
into Ras cheese. Eighty percent of the toxin was distributed into the curd and 20% into the whey. Cheese ripening effected
toxin content and the effect was temperature dependent. At 6°C: toxin concentration was slightly affected; at 20°C the toxin
was reduced by 16% after 90 days when low toxin concentration was used.
3
Formation of STG byA versicolor mold on Ras cheese. Ras cheese blocks were contaminated with spores of the mold. Toxin production started after 45 days of
ripening and reached a maximum at 90 days and then declined. Cow’s milk favoured toxin production over buffaloe’s. Aged cheese
inhibited toxin production.
Transcranial duplex sonography (TCD) of the substantia nigra has emerged as a promising, non-invasive tool to diagnose idiopathic
Parkinson's disease (IPD). However, its diagnostic accuracy in patients with undefined parkinsonism remains to be determined. 相似文献
Lung epithelial cell death is a prominent feature of acute lung injury and acute respiratory distress syndrome (ALI/ARDS), which results from severe pulmonary infection leading to respiratory failure. Multiple mechanisms are believed to contribute to the death of epithelia; however, limited data propose a role for epigenetic modifiers. In this study, we report that a chromatin modulator protein arginine N-methyltransferase 4/coactivator-associated arginine methyltransferase 1 (PRMT4/CARM1) is elevated in human lung tissues with pneumonia and in experimental lung injury models. Here PRMT4 is normally targeted for its degradation by an E3 ubiquitin ligase, SCFFBXO9, that interacts with PRMT4 via a phosphodegron to ubiquitinate the chromatin modulator at K228 leading to its proteasomal degradation. Bacterial-derived endotoxin reduced levels of SCFFBXO9 thus increasing PRMT4 cellular concentrations linked to epithelial cell death. Elevated PRMT4 protein caused substantial epithelial cell death via caspase 3-mediated cell death signaling, and depletion of PRMT4 abolished LPS-mediated epithelial cell death both in cellular and murine injury models. These findings implicate a unique molecular interaction between SCFFBXO9 and PRMT4 and its regulation by endotoxin that impacts the life span of lung epithelia, which may play a key role in the pathobiology of tissue injury observed during critical respiratory illness.Subject terms: Ligases, Epigenetics, Ubiquitin ligases, Infection相似文献
Members of La-related protein (LARP) 1 family spread widely in various species, and they are involved in regulating many important biological processes in mammal, yeast, and fruit fly. However, functional research of LARP1s in plants is limited so far. In Arabidopsis, there are three members in LARP1 family, LARP1a, 1b, and 1c. Here, we found that the mutation of LARP1 genes delayed seed germination, implying that LARP1 proteins might be positive factors of seed germination in Arabidopsis. Moreover, the larp1 mutants showed more sensitive to abscisic acid (ABA) and paclobutrazol (PAC), as larp1 mutants displayed low rate of germination in medium contained ABA or PAC. Temporal and spatial expression analyses revealed that LARP1s were more abundant in seeds, especially in imbibed seeds. Subcellular localization analysis revealed that all LARP1 proteins could localize to the P-bodies, suggesting that LARP1s might play a role in RNA processes. Taken together, our results unravel new conserved functions of LARP1s in the regulation of Arabidopsis seed germination.