Meiotic study was performed in 22 Brassica napus cultivars considering chiasma frequency and distribution as well as chromosome pairing. All cultivars possessed n = 19 chromosome number (4x) and showed a deviant course of prophase-I meiosis with synezetic knot and post pachytene diffuse stage. Chromosome stickiness occurred in most of the cultivars from early prophase to late telophase-II leading to the formation of laggard chromosomes and micronuclei. The cultivars studied differed significantly in chiasma frequency and distribution as well as bivalent formation indicating their genomic differences. Cluster analysis and ordination based on principal components analysis grouped those cultivars showing meiotic similarities. Some of the cultivars showed the occurrence of unreduced meiocytes and pollen grains.

Recent studies show that the human Merkel cell polyomavirus (MCPyV) may be involved in causing cancer. The objective of this study was to assess the impact of MCPyV on the development of head and neck squamous cell carcinoma (HNSCC). In total, 50 paraffin-embedded HNSCC biopsy samples and 50 adjacent non-cancerous samples were evaluated for the presence of MCPyV DNA and RNA. Among patients, the five most frequent histopathologic sites were the tongue (22.0%), lip (16.0%), submandibular (14.0%), cheek (14.0%), and throat (14.0%). MCPyV DNA was positive in eight (16.0%) samples. The median MCPyV LT-Ag copy number in the eight positive samples and in one non-cancerous sample was 4.8 × 10 and 2.6 × 10 copies/cell, respectively. Quantification of MCPyV LT-Ag revealed increased expression in stage III (5.6 × 10 copies/cell) than in the other stages. The MCPyV DNA load in different stages of HNSCC was also statistically significant (P = 0.027). The viral load was low, suggesting that only a fraction of cancerous cells is infected. This result provides evidence confirming the presence of MCPyV in a subset of Iranian patients with HNSCCs, but further studies needed to confirm our findings.

Our study suggested that the -579 T allele may increase the relative risk for the progression of clinicopathological characteristic of tumor grade of gastric cancer patients.

Meiotic study was performed in 50 canola (Bras sica nap us) cultivars considering chiasma frequency and distribution as well as chromosomes pairing. All cultivars possessed n = 19 chromosome number (4x). Chromosome stickiness occurred in most of the cultivars from early prophase to late telophase-II leading to the formation of laggard chromosomes and micronuclei. The cultivars studied differed significantly in chiasma frequency and distribution as well as chromosomes association indicating their genomic differences. Cluster analysis and ordination based on principal components analysis grouped those cultivars showing meiotic similarities. Some of the cultivars showed the occurrence of B-chromosomes which significantly changed chiasma frequency and chromosome pairing in the cells possessing them. Unreduced meiocytes and pollen grains were observed in some of the cultivars due to cytomixis, anaphase failure and desynapsis.

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