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Ivan Ramos-Martínez,1– 3 Oscar Vivanco-Rojas,2 Brenda Juárez-Domínguez,2 Luis Hernández-Zimbrón,1,2 Lenin Ochoa-de la Paz,1,2 Hugo Quiroz-Mercado,2 Eleazar Ramírez-Hernández,1 Rosario Gulias-Cañizo,4 Edgar Zenteno1,2 1Departamento de Bioquímica, Facultad de Medicina UNAM, Ciudad de Mexico, 04510, Mexico; 2Departamento de Investigación, Asociación para Evitar la Ceguera en Mexico I.A.P. Hospital Dr. Luis Sánchez Bulnes, Mexico City, Mexico; 3Glycobiology, Cell Growth and Tissue Repair Research Unit (Gly-CRRET), Université Paris Est Créteil (UPEC), Créteil, France; 4Centro de Investigación en Ciencias de la Salud (CICSA), Universidad Anáhuac Mexico, Huixquilucan, Estado de Mexico, MexicoCorrespondence: Rosario Gulias-Cañizo; Edgar Zenteno Email rosariogulias@yahoo.com.mx; ezenteno@servidor.unam.mxPurpose: In order to better understand cataract development, we analyzed the glycosylation profile of human lens epithelial cells (HLECs) from anterior lens capsules of type 2 diabetes mellitus (T2DM) and non-diabetic (ND) patients undergoing routine cataract surgery.Setting: Research Department of the Asociación para Evitar la Ceguera, Hospital “Dr. Luis Sánchez Bulnes”, Mexico.Design: Experimental study.Methods: Evaluation of anterior lens capsules from T2DM and ND patients undergoing phacoemulsification and free from other ocular diseases.Results: Hematoxylin-eosin staining revealed HLECs alterations in T2DM samples. From lectins with different sugar specificities used, concanavalin A showed significant differences, labeling homogeneously both in the cytoplasm and in cell membranes in ND capsules, while in T2DM capsules, in addition to membrane and cytoplasm labeling, there were perinuclear vesicles with high concanavalin A labeling. Two-dimensional gel electrophoresis showed that T2DM patients have a ∼ 65-kDa spot with an isoelectric point of 5.5 with a higher density compared to ND capsules, and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis showed 62% homology with type-1 cytokeratin. Immunohistochemistry using anti-pan cytokeratin antibody revealed co-localization with concanavalin A, and a lectin blot revealed with concanavalin A showed a band of ∼ 65 kDa, a molecular weight that corresponds to human type 1 cytokeratin.Conclusion: These results suggest that over-expression of N-glycosidically linked human type 1 cytokeratin may induce capsule disruption and affect selective permeability, allowing the entry of different molecules to the lens that facilitate cataract progression.Keywords: glycosylation, human epithelial lens cells, diabetes mellitus, cataract

The use of pesticides in agricultural production originates residues in the environment where they are applied. Pesticide aerial application is a frequent source of exposure to pesticides by persons dedicated to agricultural practices and those living in neighboring communities of sprayed fields. The aim of the study was to assess the genotoxic effects of pesticides in workers occupationally exposed to these chemicals during their aerial application to agricultural fields of Sinaloa, Mexico. The study involved 30 pilots of airplanes used to apply pesticides via aerial application and 30 unexposed controls. Damage was evaluated through the micronucleus assay and by other nuclear abnormalities in epithelial cells of oral mucosa. The highest frequency ratios (FR) equal to 269.5 corresponded to binucleated cells followed by 54.2, corresponding to cells with pyknotic nuclei, 45.2 of cells with chromatin condensation, 3.7 of cells with broken-egg, 3.6 of cells with micronucleus, and 2.0 of karyolytic cells. Age, worked time, smoking, and alcohol consumption did not have significant influence on nuclear abnormalities in the pilots studied. Pesticide exposure was the main factor for nuclear abnormality results and DNA damage. Marked genotoxic damage was developed even in younger pilots with 2 years of short working period, caused by their daily occupational exposure to pesticides. [ABSTRACT FROM AUTHOR]

The peritrophic matrix is a chitin-protein structure that envelops the food bolus in the midgut of the majority of insects, but is absent in some groups which have, instead, an unusual extra-cellular lipoprotein membrane named the perimicrovillar membrane. The presence of the perimicrovillar membrane (PMM) allows these insects to exploit restricted ecological niches during all life stages. It is found only in some members of the superorder Paraneoptera and many of these species are of medical and economic importance. In this review we present an overview of the midgut and the digestive system of insects with an emphasis on the order Paraneoptera and differences found across phylogenetic groups. We discuss the importance of the PMM in Hemiptera and the apparent conservation of this structure among hemipteran groups, suggesting that the basic mechanism of PMM production is the same for different hemipteran species. We propose that the PMM is intimately involved in the interaction with parasites and as such should be a target for biological and chemical control of hemipteran insects of economic and medical importance. [ABSTRACT FROM PUBLISHER]