Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre-including this research content-immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active.

No abstract

The diagnosis of COVID-19 diseases relies on the detection of SARS CoV-2 RNA by real time RT-PCR in respiratory samples. Rapid increase in the COVID-19 cases across the world requires fast and efficient testing as testing capacity is a bottleneck in diagnosis. In this context, pooling strategy can be opted for rapid testing in a cost-effective manner. In this study the authors have optimized and compared the effect of pooling (5 & 10 samples) before and after nucleic acid extraction. It was concluded that there was no significant difference in the SARS CoV-2 RNA detection in the pools prepared at sample or RNA level. Even after pooling, 10-fold dilution was detectable with 3 Ct value change in both type of pools when compared with individual samples. Hence, sample pool size of 10 can be used in low prevalent areas and testing capacity can be substantially increased.

No abstract

Background: Syringocystadenoma papilliferum is a benign adnexal neoplasm. Contiguous squamous proliferation has been rarely described in syringocystadenoma papilliferum. Aims: This study aimed to evaluate the spectrum and pathogenesis of contiguous squamous proliferation in syringocystadenoma papilliferum. Materials and Methods: All cases of syringocystadenoma papilliferum diagnosed over the past 12 years were screened for contiguous squamous proliferation. Cases with associated nevus sebaceous were excluded from the study. Immunohistochemistry for GATA3, CK7, BRAFV600E and p16 was performed. PCR for human papilloma virus, type 16 and 18, was carried out. Results: Of a total of 30 cases, 14 cases showed associated contiguous squamous proliferation which included four cases of verrucous hyperplasia, six cases with papillomatosis, two cases with mild squamous hyperplasia and one case each of Bowen’s disease and squamous cell carcinoma. In the cases with non-neoplastic contiguous squamous proliferations, the squamous component did not express CK7 or GATA3. However, the squamous component of premalignant and malignant lesions expressed CK7 and GATA3 concordant with the adenomatous component. BRAF was positive in adenomatous component in five cases while the contiguous squamous proliferation component was negative for BRAF in all but one case. p16 was negative in both components of all cases and PCR for human papilloma virus was negative in all cases. Limitations: Due to the rarity of disease, the sample size of our study was relatively small with two cases in the 2nd group, that is, syringocystadenoma papilliferum with malignant contiguous squamous proliferation. Detailed molecular studies such as gene sequencing were not performed. Conclusion: Syringocystadenoma papilliferum with contiguous squamous proliferation is underreported, and most commonly displays verrucous hyperplasia. The premalignant and malignant contiguous squamous proliferations likely arise from syringocystadenoma papilliferum while the hyperplastic contiguous squamous proliferations likely arise from the adjacent epidermis. Relationship with high-risk human papilloma virus is unlikely. However, further molecular analysis of larger number of cases is required to establish the pathogenesis.