The derivation and characterisation of a conditionally immortal mouse mammary epithelial cell line using a transgenic approach

The induction of proliferation and differentiation in mammary epithelium during pregnancy is quite remarkable and results in the synthesis of copious amounts of milk at parturition to feed the offspring. Understanding the key factors involved in the tissue- specific activation of the milk protein genes and their relationship to tissue organisation have been important areas of mammary gland research. Epithelial cell lines can provide invitro model systems in which both the growth and differentiation of the epithelium can be investigated under defined conditions. This thesis describes the isolation and characterisation of a conditionally immortalised mouse mammary epithelial cell line.The approach adopted utilised transgenic mice harbouring an enhancerless thermolabile mutant of SV40 T-antigen (tsA58) construct driven by the ovine (3-lactoglobulin (BLG) milk protein gene promoter as a source of mammary cells. It was envisaged that the expression of T-antigen would be limited to the secretory epithelium of the mammary gland and its immortalising properties active only at the permissive temperature of 33°C. However several of the founder mice developed tumours at ectopic sites due to leaky expression of T-antigen from the BLG promoter.Mammary tissue from the five surviving transgenic lines of mice were used to generate mammary cultures. A novel isolation procedure, exploiting the ability of explant cultures to generate epithelial outgrowths, was used. One cell line, designated KIM-2, isolated from the lowest copy transgenic line at a semi-permissive temperature of 37°C was characterised further. These cultures, established from midpregnant glands, are highly enriched with luminal cells as assessed by their strong positive staining with secretory epithelial markers (keratins 18 and 19) and have retained a stable phenotype for over 60 passages. Investigation into the functional differentiation of KIM-2 cells has shown that the induction of (3-casein is similar to existing mammary cell models. However the KIM-2 cell line has retained the ability to express a late differentiation marker, whey acidic protein (WAP) on plastic unlike other cell lines which require quite complex culture conditions to induce further differentiation. Initial transfection studies in this cell line with foreign DNA constructs has also proven to be successful. Therefore, the KIM-2 cell line has the potential to provide a good in vitro model to study factors involved in mammary epithelium development

A user evaluation of hierarchical phrase browsing

Phrase browsing interfaces based on hierarchies of phrases extracted automatically from document collections offer a useful compromise between automatic full-text searching and manually-created subject indexes. The literature contains descriptions of such systems that many find compelling and persuasive. However, evaluation studies have either been anecdotal, or focused on objective measures of the quality of automatically-extracted index terms, or restricted to questions of computational efficiency and feasibility. This paper reports on an empirical, controlled user study that compares hierarchical phrase browsing with full-text searching over a range of information seeking tasks. Users found the results located via phrase browsing to be relevant and useful but preferred keyword searching for certain types of queries. Users experiences were marred by interface details, including inconsistencies between the phrase browser and the surrounding digital library interface

The Case for Establishing a Collective Perspective to Address the Harms of Platform Personalization

Personalization on digital platforms drives a broad range of harms, including misinformation, manipulation, social polarization, subversion of autonomy, and discrimination. In recent years, policy makers, civil society advocates, and researchers have proposed a wide range of interventions to address these challenges. This Article argues that the emerging toolkit reflects an individualistic view of both personal data and data-driven harms that will likely be inadequate to address growing harms in the global data ecosystem. It maintains that interventions must be grounded in an understanding of the fundamentally collective nature of data, wherein platforms leverage complex patterns of behaviors and characteristics observed across a large population to draw inferences and make predictions about individuals. Using the lens of the collective nature of data, this Article evaluates various approaches to addressing personalization-driven harms under current consideration. It also frames concrete guidance for future legislation in this space and for meaningful transparency that goes far beyond current transparency proposals. It offers a roadmap for what meaningful transparency must constitute: a collective perspective providing a third party with ongoing insight into the information gathered and observed about individuals and how it correlates with any personalized content they receive across a large, representative population. These insights would enable the third party to understand, identify, quantify, and address cases of personalization-driven harms. This Article discusses how such transparency can be achieved without sacrificing privacy and provides guidelines for legislation to support the development of such transparency

High Sensitivity DNA Detection Using Gold Nanoparticle Functionalised Polyaniline Nanofibres

Polyaniline (PANI) nanofibres (PANI-NF) have been modified with chemically grown gold nanoparticles to give a nanocomposite material (PANI-NF–AuNP) and deposited on gold electrodes. Single stranded capture DNA was then bound to the gold nanoparticles and the underlying gold electrode and allowed to hybridise with a complementary target strand that is uniquely associated with the pathogen, Staphylococcus aureus (S. aureus), that causes mastitis. Significantly, cyclic voltammetry demonstrates that deposition of the gold nanoparticles increases the area available for DNA immobilisation by a factor of approximately 4. EPR reveals that the addition of the Au nanoparticles efficiently decreases the interactions between adjacent PANI chains and/or motional broadening. Finally, a second horseradish peroxidase (HRP) labelled DNA strand hybridises with the target allowing the concentration of the target DNA to be detected by monitoring the reduction of a hydroquinone mediator in solution. The sensors have a wide dynamic range, excellent ability to discriminate DNA mismatches and a high sensitivity. Semi-log plots of the pathogen DNA concentration vs. faradaic current were linear from 150 × 10−12 to 1 × 10−6 mol L−1 and pM concentrations could be detected without the need for molecular, e.g., PCR or NASBA, amplification

miR-7 is recruited to the High Molecular Weight 1 RNA-induced silencing complex in CD8+ T cells upon activation and suppresses IL-2 signaling

Increasing evidence suggests mammalian Argonaute (Ago) proteins partition into distinct complexes within cells, but there is still little biochemical or functional understanding of the miRNAs differentially associated with these complexes. In naïve T cells, Ago2 is found almost exclusively in low molecular weight (LMW) complexes which are associated with miRNAs but not their target mRNAs. Upon T-cell activation, a proportion of these Ago2 complexes move into a newly formed high molecular weight (HMW) RNA-induced silencing complex (RISC), which is characterized by the presence of the GW182 protein that mediates translational repression. Here, we demonstrate distinct partitioning of miRNAs and isomiRs in LMW versus HMW RISCs upon antigen-mediated activation of CD8 + T cells. We identify miR-7 as highly enriched in HMW RISC and demonstrate that miR-7 inhibition leads to increased production of IL-2 and up-regulation of the IL-2 receptor, the transferrin receptor, CD71 and the amino acid transporter, CD98. Our data support a model where recruitment of miR-7 to HMW RISC restrains IL-2 signaling and the metabolic processes regulated by IL-2. </p

Changes in patient activation following cardiac rehabilitation using the Active+me digital healthcare platform during the COVID-19 pandemic: a cohort evaluation.

BACKGROUND: Restrictions on face-to-face contact, due to COVID-19, led to a rapid adoption of technology to remotely deliver cardiac rehabilitation (CR). Some technologies, including Active+me, were used without knowing their benefits. We assessed changes in patient activation measure (PAM) in patients participating in routine CR, using Active+me. We also investigated changes in PAM among low, moderate, and high risk patients, changes in cardiovascular risk factors, and explored patient and healthcare professional experiences of using Active+me. METHODS: Patients received standard CR education and an exercise prescription. Active+me was used to monitor patient health, progress towards goals, and provide additional lifestyle support. Patients accessed Active+me through a smart-device application which synchronised to telemetry enabled scales, blood pressure monitors, pulse oximeter, and activity trackers. Changes in PAM score following CR were calculated. Sub-group analysis was conducted on patients at high, moderate, and low risk of exercise induced cardiovascular events. Qualitative interviews explored the acceptability of Active+me. RESULTS: Forty-six patients were recruited (Age: 60.4 ± 10.9 years; BMI: 27.9 ± 5.0 kg.m2; 78.3% male). PAM scores increased from 65.5 (range: 51.0 to 100.0) to 70.2 (range: 40.7 to 100.0; P = 0.039). PAM scores of high risk patients increased from 61.9 (range: 53.0 to 91.0) to 75.0 (range: 58.1 to 100.0; P = 0.044). The PAM scores of moderate and low risk patients did not change. Resting systolic blood pressure decreased from 125 mmHg (95% CI: 120 to 130 mmHg) to 119 mmHg (95% CI: 115 to 122 mmHg; P = 0.023) and waist circumference measurements decreased from 92.8 cm (95% CI: 82.6 to 102.9 cm) to 85.3 cm (95% CI 79.1 to 96.2 cm; P = 0.026). Self-reported physical activity levels increased from 1557.5 MET-minutes (range: 245.0 to 5355.0 MET-minutes) to 3363.2 MET-minutes (range: 105.0 to 12,360.0 MET-minutes; P < 0.001). Active+me was acceptable to patients and healthcare professionals. CONCLUSION: Participation in standard CR, with Active+me, is associated with increased patient skill, knowledge, and confidence to manage their condition. Active+me may be an appropriate platform to support CR delivery when patients cannot be seen face-to-face. TRIAL REGISTRATION: As this was not a clinical trial, the study was not registered in a trial registry

Cost-effectiveness of pioglitazone in type 2 diabetes patients with a history of macrovascular disease: a German perspective

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Bone Marrow Stem Cells Expressing Keratinocyte Growth Factor via an Inducible Lentivirus Protects against Bleomycin-Induced Pulmonary Fibrosis

Many common diseases of the gas exchange surface of the lung have no specific treatment but cause serious morbidity and mortality. Idiopathic Pulmonary Fibrosis (IPF) is characterized by alveolar epithelial cell injury, interstitial inflammation, fibroblast proliferation and collagen accumulation within the lung parenchyma. Keratinocyte Growth Factor (KGF, also known as FGF-7) is a critical mediator of pulmonary epithelial repair through stimulation of epithelial cell proliferation. During repair, the lung not only uses resident cells after injury but also recruits circulating bone marrow-derived cells (BMDC). Several groups have used Mesenchymal Stromal Cells (MSCs) as therapeutic vectors, but little is known about the potential of Hematopoietic Stem cells (HSCs). Using an inducible lentiviral vector (Tet-On) expressing KGF, we were able to efficiently transduce both MSCs and HSCs, and demonstrated that KGF expression is induced in a regulated manner both in vitro and in vivo. We used the in vivo bleomycin-induced lung fibrosis model to assess the potential therapeutic effect of MSCs and HSCs. While both populations reduced the collagen accumulation associated with bleomycin-induced lung fibrosis, only transplantation of transduced HSCs greatly attenuated the histological damage. Using double immunohistochemistry, we show that the reduced lung damage likely occurs through endogenous type II pneumocyte proliferation induced by KGF. Taken together, our data indicates that bone marrow transplantation of lentivirus-transduced HSCs can attenuate lung damage, and shows for the first time the potential of using an inducible Tet-On system for cell based gene therapy in the lung

Tetrathiafulvalene-oligofluorene star-shaped systems : new semiconductor materials for fluorescent moisture indicators

A series of novel star-shaped oligofluorene–thiophene–tetrathiafulvalene systems have been synthesised, following different synthetic routes. Each system incorporates a tetrathiafulvalene redox-active centre and four oligofluorene arms, providing a two-dimensional character to the conjugated backbone. The oligomers differ in the number of fluorene units present in the arms (1 to 4) and the terminal groups at the end of each arm (H or trimethylsilyl). Half-unit oligofluorene systems possessing a 1,3-dithiole-2-one core (a known precursor to the tetrathiafulvalene centre) have been synthesised in order to compare the thermal, optical and electrochemical properties. These half-unit systems consist of a 1,3-dithiole-2-one core fused to a thiophene unit at the 3- and 4-positions. Two oligofluorene arms consisting of 1 to 4 monomer units per arm are positioned at the 4- and 6-positions of the thiophene unit, affording extended conjugation through the thiophene centre. The half-unit systems are found to be moderate emitters in solution, however, the star-shaped systems bearing the tetrathiafulvalene core exhibit inhibited fluorescence in both solution and the solid state. We have demonstrated that the emission of the tetrathiafulvalene systems can be enhanced through the oxidation of the redox-centre followed by a consecutive reaction of the strongly electrophilic tetrathiafulvalene dication with such nucleophiles as water and hydrazine. The result of these reactions leads to an increase in the photoluminescence of these systems, affording the opportunity for the tetrathiafulvalene materials to be used as photonic materials in moisture indicators

Use of GRADE for assessment of evidence about prognosis: rating confidence in estimates of event rates in broad categories of patients.

Summary pointsMain concepts- The Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach defines quality of evidence as confidence in effect estimates; this conceptualization can readily be applied to bodies of evidence estimating the risk of future of events (that is, prognosis) in broadly defined populations- In the field of prognosis, a body of observational evidence (including single arms of randomized controlled trials) begins as high quality evidence- The five domains GRADE considers in rating down confidence in estimates of treatment effect—that is, risk of bias, imprecision, inconsistency, indirectness, and publication bias—as well as the GRADE criteria for rating up quality, also apply to estimates of the risk of future of events from a body of prognostic studies- Applying these concepts to systematic reviews of prognostic studies provides a useful approach to determine confidence in estimates of overall prognosis in broad populationsLay summary- The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach to rating confidence in the results of research studies was initially developed for therapeutic questions- The GRADE approach considers study design (randomized trials versus non-randomized designs), risk of bias, inconsistency, imprecision, indirectness, and publication bias; size and trend in the effect are also considered- Observational studies looking at patients’ prognosis may provide robust estimates of the likelihood of undesirable or desirable outcomes in both treated and untreated patients- Patients will often find this information helpful in understanding the likely course of their disease, in planning their future, and in engaging in shared decision making with their healthcare providers- In a previous article, we examined factors that affect confidence in estimates of baseline risk (the risk of bad outcomes in untreated patients), providing examples of how this might influence the confidence in estimates of absolute treatment effect- This paper provides guidance for the use of the GRADE approach to determine confidence in estimates of future events in systematic reviews of prognostic studies in broad categories of patient