Pre-harvest burning of sugarcane fields produces large amounts of air pollutants which are known to cause health problems, including ocular surface abnormalities. In this study, we evaluated the effect of biomass burning on mucus quality and mucin gene expression (MUC1, MUC5AC, MUC16) in the conjunctiva of sugarcane workers (SWs) and residents of an adjacent town (RTs). Impression cytology samples of the inferior tarsal and bulbar conjunctiva of 78 SWs and 32 RTs were collected before (T1) and immediately after (T2) a 6-month harvest period. The neutral, acid and total mucus content of goblet cells was determined by PAS and AB staining. The levels of MUC5AC, MUC1 and MUC16 mRNA in the conjunctiva were measured by real-time PCR. Compared to RTs, SWs had higher levels of bulbar acid mucus and MUC16 mRNA and tarsal MUC5AC mRNA at T2 and lower levels of neutral mucus at T1 and T2. In the SW group, MUC1 mRNA levels were higher at T2 than at T1, but the levels of neutral and acid mucus were similar. In the RT group, acid mucus decreased and neutral mucus increased in the bulbar and tarsal conjunctiva at T2. In conclusion, our findings show that sugarcane harvesting is associated with abnormalities in mucus quality and content and changes in mucin mRNA levels on the ocular surface. This may help explain the ocular inflammatory signs and symptoms observed in subjects exposed to air pollutants and high temperatures from sugarcane biomass burning.

中文翻译：

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巴西小组研究：甘蔗生物量燃烧对收获工人和邻近城镇居民结膜黏蛋白分布的影响。

甘蔗田收割前燃烧会产生大量空气污染物，已知这些污染物会引起健康问题，包括眼表异常。在这项研究中，我们评估了生物质燃烧对甘蔗工人（SW）和邻近城镇（RT）居民结膜中黏液质量和黏蛋白基因表达（MUC1，MUC5AC，MUC16）的影响。在六个月的收获期之前（T1）和之后（T2），收集了78个SW和32个RT的下睑板和延髓结膜的印象细胞学样本。通过PAS和AB染色确定杯状细胞的中性，酸性和总粘液含量。通过实时PCR检测结膜中MUC5AC，MUC1和MUC16 mRNA的水平。与实时出价相比，SW在T2时具有较高的球茎酸性黏液和MUC16 mRNA和MUC5AC mRNA水平，而在T1和T2时具有较低的中性黏液水平。在西南组，MUC1 mRNA水平在T2高于T1，但中性和酸性黏液水平相似。在RT组，在T2时，延髓和睑结膜的酸性粘液减少而中性粘液增加。总之，我们的发现表明，甘蔗的收获与粘液质量和含量的异常以及眼表面粘蛋白mRNA水平的变化有关。这可能有助于解释在暴露于空气污染物和甘蔗生物质燃烧引起的高温的受试者中观察到的眼部炎症迹象和症状。在RT组，在T2时，延髓和睑结膜的酸性粘液减少而中性粘液增加。总之，我们的发现表明，甘蔗的收获与粘液质量和含量的异常以及眼表面粘蛋白mRNA水平的变化有关。这可能有助于解释在暴露于空气污染物和甘蔗生物质燃烧引起的高温的受试者中观察到的眼部炎症迹象和症状。在RT组，在T2时，延髓和睑结膜的酸性粘液减少而中性粘液增加。总之，我们的发现表明，甘蔗的收获与粘液质量和含量的异常以及眼表面粘蛋白mRNA水平的变化有关。这可能有助于解释在暴露于空气污染物和甘蔗生物质燃烧引起的高温下的受试者中观察到的眼部炎症迹象和症状。