Phage‐mediated transfer of virulence genes

Bacteriophages as accessory genetic elements play a crucial role in the dissemination of genes and the promotion of genetic diversity within bacterial populations. Such horizontal transfer of DNA is critical in the emergence of new pathogenic organisms, through the dissemination of genes encoding virulence factors such as toxins, adhesins and agressins. Phages can transfer genes that are not necessary for bacteriophage persistence and are generally recognised by their ability to convert their host bacteria to new phenotypes. This phenomenon is known as phage conversion. If such converting genes encode for virulence factors, the consequences of phage infection may include increased virulence of the host bacteria, and the conversion of a non‐pathogenic strain to a potentially dangerous pathogen. A number of virulence factors in bacteria causing diseases in plants, animals and humans are encoded by converting phages, the vast majority of which are temperate as opposed to lytic in nature. © 2001 Society of Chemical Industry     

Designing intersections—designing subjectivity: Feminist theory and praxis in a sex discrimination legislation system

This paper looks at the intersections between feminist epistemology, feminist jurisprudence and research on artificial intelligence and the law. It is suggested that feminist theory highlights the role of subjectivity which is ignored in the traditional epistemology of AI systems. This allows AI systems to appear to be “perspectiveless” when they may be tacitly used in a normative role which ignores alternative knowledges. The paper looks at the Cyc system as an example. In developing an expert system to advise on Sex Discrimination law a number of lessons are learned both from the Forms Helper system and more particularly from feminist jurisprudence and from the critique of AI from feminist epistemology.     

Tolerogenic Iron Oxide Nanoparticles in Type 1 Diabetes: Biodistribution and Pharmacokinetics Studies in Nonobese Diabetic Mice

Nanoparticle (NP) administration is among the most attractive approaches to exploit the synergy of different copackaged molecules for the same target. In this work, iron oxide NPs are surface‐engineered for the copackaging of the autoantigen proinsulin, a major target of adaptive immunity in type 1 diabetes (T1D), and 2‐(1′H‐indole‐3′‐carbonyl)‐thiazole‐4‐carboxylic acid methylester (ITE), a small drug conditioning a tolerogenic environment. Magnetic resonance imaging (MRI) combined with magnetic quantification are used to investigate NP biokinetics in nonobese diabetic (NOD) mice and control mice in different organs. Different NP biodistribution, with in particular enhanced kidney elimination and a stronger accumulation in the pancreas for prediabetic NOD mice, is observed. This is related to preferential NP accumulation in the pancreatic inflammatory zone and to enhancement of renal elimination by diabetic nephropathy. For both mouse strains, an MRI T2 contrast enhancement at 72 h in the liver, pancreas, and kidneys, and indicating recirculating NPs, is also found. This unexpected result is confirmed by magnetic quantification at different time points as well as by histological evaluation. Besides, such NPs are potential MRI contrast agents for early diagnosis of T1D.     

Photoinducible Oncometabolite Detection

Dysregulated metabolism can fuel cancer by altering the production of bioenergetic building blocks and directly stimulating oncogenic gene-expression programs. However, relatively few optical methods for the direct study of metabolites in cells exist. To address this need and facilitate new approaches to cancer treatment and diagnosis, herein we report an optimized chemical approach to detect the oncometabolite fumarate. Our strategy employs diaryl tetrazoles as cell-permeable photoinducible precursors to nitrileimines. Uncaging these species in cells and cell extracts enables them to undergo 1,3-dipolar cycloadditions with endogenous dipolarophile metabolites such as fumarate to form pyrazoline cycloadducts that can be readily detected by their intrinsic fluorescence. The ability to photolytically uncage diaryl tetrazoles provides greatly improved sensitivity relative to previous methods, and enables the facile detection of dysregulated fumarate metabolism through biochemical activity assays, intracellular imaging, and flow cytometry. Our studies showcase an intersection of bioorthogonal chemistry and metabolite reactivity that can be applied for biological profiling, imaging, and diagnostics.     

Patterns of stability in adult attachment: An empirical test of two models of continuity and change.

One of the core assumptions of attachment theory is that attachment representations are stable over time. Unfortunately, the data on attachment stability have been ambiguous, and as a result, alternative theoretical perspectives have evolved to explain them. The objective of the present research was to evaluate alternative models of stability by studying adults in 2 intensive longitudinal investigations. Specifically, we assessed attachment representations in 1 sample (N = 203) daily over a 30-day period and in the other sample (N = 388) weekly over a year. Analyses show that the patterns of stability that exist in adult attachment are most consistent with a prototype model—a model assuming that there is a stable factor underlying temporary variations in attachment. Moreover, although the Big Five personality traits exhibited a pattern of stability that was similar to that of attachment, they did not account for the stability observed in attachment. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Impacts of stress on estimation performance in Hong Kong

Cost estimation not only requires precise technical and analytical input from estimators but also involves the use of subjective judgement. An investigation on the impact of stress on estimation performance was conducted involving 177 professional estimators in Hong Kong. Using correlation analysis, regression analysis and structural equation modelling, the relationships between stress and various aspects of estimation performance are examined and a causal structural model is developed. The results indicate that stress is a cause of negative estimation performance (resulting in weak interpersonal relationships, unfamiliarity with organization and ineffective process), while, simultaneously, it is beneficial to the professional estimation performance. Furthermore, there is an inverted U‐shaped relationship between stress and the organizational relationship.     

Antioxidant and anticancer capacity of saponin‐enriched Carica papaya leaf extracts

The papaya (Carica papaya) leaf (PL) contains high levels of saponins and polyphenolic compounds, and historically, it has been used as a folk medicine for numerous ailments, including cancer. PL is traditionally prepared by hot water extraction; however, optimised extraction conditions have not been assessed. This study optimised conditions for the extraction of saponins from PL and assessed their antioxidant capacity and antipancreatic cancer activity. Optimisation was achieved using response surface methodology. Saponins and total phenolic compounds were assessed for their antioxidant, free radical scavenging, ion‐reducing capacity, and antipancreatic cancer activity. Optimal aqueous extraction conditions were 85 °C, 25 min. and a water‐to‐leaf ratio of 20:1 mL g^?1. Ethanol extracts demonstrated higher antioxidant, free radical scavenging and ion‐reducing capacity, as well as antipancreatic cancer activity. This study revealed that the PL contains numerous bioactive compounds, with significant anticancer activity warranting further studies on the isolation and characterisation of individual bioactive compounds from the PL.     

Mitochondrial Optic Atrophy (OPA) 1 Processing Is Altered in Response to Neonatal Hypoxic-Ischemic Brain Injury

Perturbation of mitochondrial function and subsequent induction of cell death pathways are key hallmarks in neonatal hypoxic-ischemic (HI) injury, both in animal models and in term infants. Mitoprotective therapies therefore offer a new avenue for intervention for the babies who suffer life-long disabilities as a result of birth asphyxia. Here we show that after oxygen-glucose deprivation in primary neurons or in a mouse model of HI, mitochondrial protein homeostasis is altered, manifesting as a change in mitochondrial morphology and functional impairment. Furthermore we find that the mitochondrial fusion and cristae regulatory protein, OPA1, is aberrantly cleaved to shorter forms. OPA1 cleavage is normally regulated by a balanced action of the proteases Yme1L and Oma1. However, in primary neurons or after HI in vivo, protein expression of YmelL is also reduced, whereas no change is observed in Oma1 expression. Our data strongly suggest that alterations in mitochondria-shaping proteins are an early event in the pathogenesis of neonatal HI injury.     

Using revealed mate preferences to evaluate market force and differential preference explanations for mate selection.

In this article the authors illustrate how revealed preferences (i.e., preferences inferred through an individual’s differential attraction to multiple targets) can be used to investigate the nature of mate preferences. The authors describe how revealed preferences can be estimated and how the reliability of these estimates can be established. Revealed preference estimates were used to explore the level of consensus in judgments of who is and is not attractive and whether revealed preferences are systematically related to self-reported mate preferences and personality traits. Revealed preference estimates were created for over 4,000 participants by examining their attraction to 98 photographs. Participants of both genders showed substantial consensus in judgments of whom they found attractive and unattractive, although men showed higher consensus than women. Revealed preference estimates also showed relationships with corresponding self-rated preferences and with other dispositional characteristics such as personality traits and age. Although the findings demonstrate the existence of meaningful individual differences in preferences, they also indicate an important role for consensual preferences in mate selection processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)