A simple 'paper smear' method for dry collection, transport and storage of cervical cytological specimens for rapid screening of HPV infection by PCR

Human papillomaviruses (HPVs) are major pathogens associated with the development of cancer of the uterine cervix, the most common malignant tumour of women world-wide. Reliable diagnosis of HPV infection, particularly the 'high-risk' types (16/18), may facilitate early identification of 'high-risk' populations for developing cervical cancer and may augment the sensitivity and specificity of primary cervical cancer screening programmes by complementing the conventional Pap test. A simple paper smear method has been developed for dry collection, transport and storage of cervical smears/scrapes at room temperature for subsequent detection of HPV DNA by PCR assay. Imprint biopsies, blood and fine-needle aspirates were also collected by this method. The cervical scrapes or other body fluids were smeared (within 0.5-1 cm diameter) and dried on to sterile small slides made of Whatman 3MM filter paper, and stored individually at room temperature or at 4°C. A small piece (2-3 mm) of the paper smear was punched or cut out with a sterile surgical blade, boiled in an eppendorf tube containing 50 µl of distilled water for 5 min and used directly for PCR amplification. The quality and quantity of DNA derived from paper smears and the results of PCR amplifications for HPV type 16, BRCA1 and p53 genes were identical to those obtained from the same samples following collection in PBS, storage (-70°C) and phenol-chloroform-based DNA extraction. DNA was stable in the paper smears for up to a year, whether stored at room temperature or at 4°C. This method is simple, rapid and cost-effective, and can be effectively employed for large-scale population screening, especially for regions where the specimens are to be transported from distant places to the laboratory

Detection of human papillomavirus DNA sequences in cancer of the urinary bladder by in situ hybridisation and polymerase chain reaction

Objective: To evaluate the prevalence of "high risk" human papillomavirus type 16 (HPV 16) in transitional cell carcinoma of the urinary bladder. Materials and Methods: The study included 10 biopsy specimens from male patients of transitional cell carcinoma of the urinary bladder for the detection of HPV DNA sequences. Specimens were collected from the Urology Clinic of the K.G. Medical College Hospital, Lucknow, India. Detection of HPV DNA was carried out by tissue in situ hybridisation (a single copy gene localisation method) using 3H-labelled HPV DNA probe and also by polymerase chain reaction (PCR) techniques using primers to HPV 16 upstream regulatory region (URR). RESULTS--Out of 10 cases of transitional cell carcinoma of the urinary bladder, "high risk" HPV 16 DNA was detected only in one (10%) by using in situ hybridisation whereas two cases (20%) were found to be positive by polymerase chain reaction. Conclusion: Our results suggest that the rare occurrence of HPV in bladder carcinoma may not have a causal relation with the viral infection

Two remarks on generalized entropy power inequalities

This note contributes to the understanding of generalized entropy power inequalities. Our main goal is to construct a counter-example regarding monotonicity and entropy comparison of weighted sums of independent identically distributed log-concave random variables. We also present a complex analogue of a recent dependent entropy power inequality of Hao and Jog, and give a very simple proof.Comment: arXiv:1811.00345 is split into 2 papers, with this being on

Intracellular growth of Mycobacterium tuberculosis after macrophage cell death leads to serial killing of host cells

A hallmark of pulmonary tuberculosis is the formation of macrophage-rich granulomas. These may restrict Mycobacterium tuberculosis (Mtb) growth, or progress to central necrosis and cavitation, facilitating pathogen growth. To determine factors leading to Mtb proliferation and host cell death, we used live cell imaging to track Mtb infection outcomes in individual primary human macrophages. Internalization of Mtb aggregates caused macrophage death, and phagocytosis of large aggregates was more cytotoxic than multiple small aggregates containing similar numbers of bacilli. Macrophage death did not result in clearance of Mtb. Rather, it led to accelerated intracellular Mtb growth regardless of prior activation or macrophage type. In contrast, bacillary replication was controlled in live phagocytes. Mtb grew as a clump in dead cells, and macrophages which internalized dead infected cells were very likely to die themselves, leading to a cell death cascade. This demonstrates how pathogen virulence can be achieved through numbers and aggregation states. DOI: http://dx.doi.org/10.7554/eLife.22028.00

High-risk human papillomavirus infections in breast cancer in Syrian women and their association with Id-1 expression: a tissue microarray study

High-risk human papillomaviruses (HPVs) could be important risk factors for breast carcinogenesis and metastasis. Based on this hypothesis, we recently studied the effect of E6/E7 onco-proteins of high-risk HPV type 16 in two non-invasive human breast cancer cell lines, BT20 and MCF7; we reported that E6/E7 converts these cell lines to invasive cells. This is accompanied by an overexpression of Id-1, which is an important regulator of breast metastasis. In this investigation, we examined the presence of high-risk HPVs (16, 18, 31, 33 and 35) and the expression of their E6 onco-protein as well as their correlation with Id-1 gene expression, using polymerase chain reaction (PCR) and tissue microarray (TMA) analysis, respectively, in a cohort of 113 Syrian breast cancer patients. We found that high-risk HPV types 16, 18, 31, 33 and 35 are present in 8.84, 9.73, 7.07, 55.75 and 37.16% of our samples, respectively, which represent invasive breast cancers. Overall, 69 (61.06%) of the 113 samples are HPV positive; among these specimens 24 tissues (34.78%) are coinfected with more than one HPV type. Furthermore, we report that the expression of the E6 onco-protein of these high-risk HPVs is correlated with Id-1 overexpression in the majority of invasive breast cancer tissue samples. Our data suggest that high-risk HPV infections are associated with human breast cancer progression in Syrian women