Polymerase Chain Reaction

Polymerase chain reaction (PCR) is an efficient and one of the most common methods used in biological sciences for in vitro multiplication of a target DNA molecule. The technique has significantly contributed in changing and developing different fields of biological sciences since 1980s. PCR has a vital role in supporting the processes involved in genetic engineering, particularly the cloning of DNA fragments used to modify the genomes of microorganisms, animals, and plants. Consequently, the technique has numerous applications in fundamental and applied research in medicine agriculture, environment, and bio-industry. The main focus of this chapter is to describe briefly the principles, methodology, various types, and applications of PCR in different fields. Besides, different components of PCR, trouble shooting during the execution, and limitations of the techniques are also outlined

Substantial and sustained reduction in under-5 mortality, diarrhea, and pneumonia in Oshikhandass, Pakistan : Evidence from two longitudinal cohort studies 15 years apart

Funding Information: Study 1 was funded through the Applied Diarrheal Disease Research Program at Harvard Institute for International Development with a grant from USAID (Project 936–5952, Cooperative Agreement # DPE-5952-A-00-5073-00), and the Aga Khan Health Service, Northern Areas and Chitral, Pakistan. Study 2 was funded by the Pakistan US S&T Cooperative Agreement between the Pakistan Higher Education Commission (HEC) (No.4–421/PAK-US/HEC/2010/955, grant to the Karakoram International University) and US National Academies of Science (Grant Number PGA-P211012 from NAS to the Fogarty International Center). The funding bodies had no role in the design of the study, data collection, analysis, interpretation, or writing of the manuscript. Publisher Copyright: © 2020 The Author(s).Peer reviewedPublisher PD

Gender digital divide in rural Pakistan : to measure and to bridge it; revised final technical report, November 2007 - April 2010

While Pakistan’s National Information Technology (IT) Policy aims at harnessing the potential of information and communication technologies (ICTs) for development, especially in the underserved rural areas, it by and large ignores the role of existing gender inequalities on the possible benefits of ICTs. We have investigated aspects of the ‘gender digital divide’ in rural areas of Pakistan. In doing so, we have generated evidence and raised awareness regarding the gaps existing among women and men’s, and girls and boys’ access to, and use of, ICTs. These discrepancies were analysed in order to better understand their impact on human development in general and women’s empowerment in particular. Through the study results, we hope to enable an evidence-based, gender-sensitive revision of the policy as well as ICT-related interventions from which both females and males gain. The study took place in four of the most marginalized rural districts of the country where this divide is likely to be most pronounced. The sampling strategy was motivated by the assumption that such extreme cases may be especially enlightening, in particular in the context of directly policy-relevant research. In the present context, we assumed that the selection of rural districts characterized by greater degree of deprivation in terms of income, education and health may provide a more robust base for policy recommendations intended to narrow the gender digital divide. A mixed methods study was undertaken, combining a questionnaire-based survey and focus group discussion. While the quantitative data, generated by randomly selected sample, provides a basis for generalisation, the focus on female FGD participants was motivated by the need to give a voice to stakeholders whose situation and interests are poorly represented in related policy discourses in Pakistan. The data suggest mobile phones to be the ICT that is most commonly available in rural Pakistan. Radios are the second and TV sets are third most widespread technologies in marginalised rural areas. Despite the wide reach of mobile phones, mobile sets at hand are largely owned by women’s husbands, fathers and brothers, whose permission to make calls is required by a large share of all female respondents. We, therefore, argue that availability and gendered use of ICTs are two different things altogether. Social norms related to women and girls’ access to education as well as regulating their mobility prevent them from using ICTs. These norms have to be taken into account in policies and interventions to ensure women and girls’ access to and beneficial use of ICTs

Introductions to the Community: Early-Career Researchers in the Time of COVID-19

10.1016/j.stem.2020.10.008CELL STEM CELL275702-70

Usp16 contributes to somatic stem-cell defects in Down's syndrome.

Down's syndrome results from full or partial trisomy of chromosome 21. However, the consequences of the underlying gene-dosage imbalance on adult tissues remain poorly understood. Here we show that in Ts65Dn mice, which are trisomic for 132 genes homologous to genes on human chromosome 21, triplication of Usp16 reduces the self-renewal of haematopoietic stem cells and the expansion of mammary epithelial cells, neural progenitors and fibroblasts. In addition, Usp16 is associated with decreased ubiquitination of Cdkn2a and accelerated senescence in Ts65Dn fibroblasts. Usp16 can remove ubiquitin from histone H2A on lysine 119, a critical mark for the maintenance of multiple somatic tissues. Downregulation of Usp16, either by mutation of a single normal Usp16 allele or by short interfering RNAs, largely rescues all of these defects. Furthermore, in human tissues overexpression of USP16 reduces the expansion of normal fibroblasts and postnatal neural progenitors, whereas downregulation of USP16 partially rescues the proliferation defects of Down's syndrome fibroblasts. Taken together, these results suggest that USP16 has an important role in antagonizing the self-renewal and/or senescence pathways in Down's syndrome and could serve as an attractive target to ameliorate some of the associated pathologies

A Quiescent Bcl11b High Stem Cell Population Is Required for Maintenance of the Mammary Gland

Stem cells in many tissues sustain themselves by entering a quiescent state to avoid genomic insults and to prevent exhaustion caused by excessive proliferation. In the mammary gland, the identity and characteristics of quiescent epithelial stem cells are not clear. Here, we identify a quiescent mammary epithelial cell population expressing high levels of Bcl11b and located at the interface between luminal and basal cells. Bcl11bhigh cells are enriched for cells that can regenerate mammary glands in secondary transplants. Loss of Bcl11b leads to a Cdkn2a-dependent exhaustion of ductal epithelium and loss of epithelial cell regenerative capacity. Gain- and loss-of-function studies show that Bcl11b induces cells to enter the G0 phase of the cell cycle and become quiescent. Taken together, these results suggest that Bcl11b acts as a central intrinsic regulator of mammary epithelial stem cell quiescence and exhaustion and is necessary for long-term maintenance of the mammary gland