RESUMEN

Genomic data analysis is a fundamental system for monitoring pathogen evolution and the outbreak of infectious diseases. Based on bioinformatics and deep learning, this study was designed to identify the genomic variability of SARS-CoV-2 worldwide and predict the impending mutation rate. Analysis of 259044 SARS-CoV-2 isolates identify 3334545 mutations (14.01 mutations per isolate), suggesting a high mutation rate. Strains from India showed the highest no. of mutations (48) followed by Scotland, USA, Netherlands, Norway, and France having up to 36 mutations. Besides the most prominently occurring mutations (D416G, F106F, P314L, and UTR:C241T), we identify L93L, A222V, A199A, V30L, and A220V mutations which are in the top 10 most frequent mutations. Multi-nucleotide mutations GGG>AAC, CC>TT, TG>CA, and AT>TA have come up in our analysis which are in the top 20 mutational cohort. Future mutation rate analysis predicts a 17%, 7%, and 3% increment of C>T, A>G, and A>T, respectively in the future. Conversely, 7%, 7%, and 6% decrement is estimated for T>C, G>A, and G>T mutations, respectively. T>G\A, C>G\A, and A>T\C are not anticipated in the future. Since SARS-CoV-2 is evolving continuously, our findings will facilitate the tracking of mutations and help to map the progression of the COVID-19 intensity worldwide.

RESUMEN

BACKGROUND/AIMS: Recent data suggest that the incidence of ulcerative colitis (UC) related colorectal cancer (CRC) in India is similar to that of West. The optimum method for surveillance is still a debate. Surveillance with random biopsies has been the standard of care, but is a tedious process. We therefore undertook this study to assess the yield of random biopsy in dysplasia surveillance. METHODS: Between March 2014 and July 2015, patients of UC attending the Inflammatory Bowel Disease clinic at the All India Institute of Medical Sciences with high risk factors for CRC like duration of disease >15 years and pancolitis, family history of CRC, primary sclerosing cholangitis underwent surveillance colonoscopy for dysplasia. Four quadrant random biopsies at 10 cm intervals were taken (33 biopsies). Two pathologists examined specimens for dysplasia, and the yield of dysplasia was calculated. RESULTS: Twenty-eight patients were included. Twenty-six of these had pancolitis with a duration of disease greater than 15 years, and two patients had associated primary sclerosing cholangis. No patient had a family history of CRC. The mean age at onset of disease was 28.89±8.73 years and the duration of disease was 19.00±8.78 years. Eighteen patients (64.28%) were males. A total of 924 biopsies were taken. None of the biopsies revealed any evidence of dysplasia, and 7/924 (0.7%) were indefinite for dysplasia. CONCLUSIONS: Random biopsy for surveillance in longstanding extensive colitis has a low yield for dysplasia and does not suffice for screening. Newer techniques such as chromoendoscopy-guided biopsies need greater adoption.

Asunto(s)

RESUMEN

Urachal carcinoma is an uncommon neoplasm. Benign urachal tumours are extremely rare. All urachal mucinous tumours, regardless of tumour type, have the potential to behave in an aggressive clinical manner that includes the development of pseudomyxoma peritonei. We report a 58-year-old man who presented with lower abdominal pain. Ultrasound and CT imaging defined a large lobulated cystic mass superior to the urinary bladder. At laparotomy, the multiloculated cystic mass, 10 x 8 x 6 cm, could be completely separated from the bladder and was excised. It was smooth-walled and filled with thick mucinous fluid. Histology revealed a complex mucinous cystadenoma of undetermined malignant potential of the urachus. The cystic spaces were lined by mucin-secreting columnar epithelium that showed focal areas of mild atypia. The epithelium lacked architectural features of villous adenoma. There was no stromal invasion to support an invasive neoplastic process. No pseudomyxoma peritonei was present. The patient was well, with no tumour recurrence, at 6 months follow-up.

Asunto(s)

RESUMEN

Urachal carcinoma is an uncommon neoplasm. Benign urachal tumours are extremely rare. All urachal mucinous tumours, regardless of tumour type, have the potential to behave in an aggressive clinical manner that includes the development of pseudomyxoma peritonei. We report a 58-year-old man who presented with lower abdominal pain. Ultrasound and CT imaging defined a large lobulated cystic mass superior to the urinary bladder. At laparotomy, the multiloculated cystic mass, 10 x 8 x 6 cm, could be completely separated from the bladder and was excised. It was smooth-walled and filled with thick mucinous fluid. Histology revealed a complex mucinous cystadenoma of undetermined malignant potential of the urachus. The cystic spaces were lined by mucin-secreting columnar epithelium that showed focal areas of mild atypia. The epithelium lacked architectural features of villous adenoma. There was no stromal invasion to support an invasive neoplastic process. No pseudomyxoma peritonei was present. The patient was well, with no tumour recurrence, at 6 months follow-up.