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Biofilms are widely recognized as a prominent mode of microbial growth and strategy of antimicrobial tolerance in many environments. Characteristics that are often overlooked in biofilm investigations include the examination of metabolic pathways as the assumption might be that interference with central pathways such as glycolysis would only reduce growth and thus not be meaningful. Using the Keio collection of Escherichia coli mutants, we investigated the influence of biofilm formation and planktonic growth in full-strength and diluted Luria–Bertani (LB) broths using strains with a disruption of glycolysis (Δpgi), the Entner–Doudoroff pathway (Δedd), or the pentose phosphate pathway (Δgnd). Unexpectedly, in contrast to the E. coli Keio parent strain (BW25113), planktonic growth was enhanced in full strength and diluted LB broths in the metabolic mutants. Using a microtiter biofilm assay, the E. coli parent strain showed the highest crystal violet staining. However, when analyzed by culture assays, there was an increase in biofilm populations in the mutants in comparison to the parent strain. Fluorescence microscopy showed differences in colonization patterns in the strains. Given the availability of mutant collections in many model organisms, similar metabolic studies are warranted for biofilms, given their importance in nature. [ABSTRACT FROM AUTHOR]

Currently, women are disadvantaged compared to men in colorectal cancer (CRC) screening, particularly in programmes that use faecal immunochemical tests for haemoglobin (FIT) followed by colonoscopy. Although there is no single cause for all the known disadvantages, many can be attributed to the ubiquitous finding that women have lower faecal haemoglobin concentrations (f-Hb) than men; there are many plausible reasons for this. Generally, a single f-Hb threshold is used in CRC screening programmes, leading to lower positivity for women than men, which causes poorer outcomes for women, including lower CRC detection rate, higher interval cancer (IC) proportion, and higher CRC mortality. Many of the now widely advocated risk scoring strategies do include factors taking account of sex, but these have not been extensively piloted or introduced. Using different f-Hb thresholds for the sexes seems advantageous, but there are difficulties, including deciding which characteristic should be selected to achieve equivalency, for example, positivity, IC proportions, or specificity. Moreover, additional colonoscopy resources, often constrained, would be required. Governments and their agencies should be encouraged to prioritise the allocation of resources to put simple strategies into practice, such as different f-Hb thresholds to create equal positivity in both sexes. [ABSTRACT FROM AUTHOR]

In this essay I contrast Freud's account of mourning in Mourning and Melancholia to that of Merleau-Ponty in Phenomenology of Perception. In suggesting a somatic as well as a psychic response, Merleau-Ponty, I argue, more accurately accounts for the ways in which we experience loss and why, contrary to Freud's suggestion, mourning's work is never completed. [ABSTRACT FROM AUTHOR]

Aim: Lower gastrointestinal (GI) symptoms are poor predictors of colorectal cancer (CRC). The aim of this study was to examine the diagnostic yield of colonoscopy by faecal haemoglobin (f‐Hb) concentration in symptomatic patients assessed in primary care by faecal immunochemical testing (FIT). Method: In three Scottish NHS Boards, FIT kits (HM‐JACKarc, Hitachi Chemical Diagnostics Systems Co., Ltd, Tokyo, Japan) were used by general practitioners to guide referrals for patients with lower GI symptoms (laboratory data studied for 12 months from December 2015 onwards in Tayside, 18 months from June 2018 onwards in Fife and 5 months from September 2018 onwards in Greater Glasgow and Clyde). Cases of CRC diagnosed at colonoscopy were ascertained from colonoscopy and pathology records. Results: Four thousand eight hundred and forty one symptomatic patients who underwent colonoscopy after FIT submission were included. Of the 2166 patients (44.7%) with f‐Hb <10 µg Hb/g faeces (µg/g), 14 (0.6%) were diagnosed with CRC, with a number needed to scope (NNS) of 155. Of the 2675 patients (55.3%) with f‐Hb ≥10 µg/g, 252 were diagnosed with CRC (9.4%) with a NNS of 11. Of the 705 patients with f‐Hb ≥400 µg/g, 158 (22.4%) were diagnosed with CRC with a NNS of 5. Over half of those diagnosed with CRC with f‐Hb <10 µg/g had coexisting anaemia. Conclusion: Symptomatic patients with f‐Hb ≥10 µg/g should undergo further investigation for CRC, while higher f‐Hb concentrations could be used to triage for urgency during the COVID‐19 recovery phase. Patients with f‐Hb <10 µg/g and without anaemia are very unlikely to be diagnosed with CRC and the majority need no further investigation. [ABSTRACT FROM AUTHOR]

Objectives: Faecal immunochemical tests for haemoglobin (FIT) are becoming widely used in colorectal cancer (CRC) screening and assessment of symptomatic patients. Faecal haemoglobin concentration (f-Hb) thresholds are used to guide subsequent investigation. We established the distributions of f-Hb in a large screening population by sex, age, deprivation and geography. Methods: Single estimates of f-Hb were documented for all individuals participating in the first 18 months of the Scottish Bowel Screening Programme (SBoSP). The distributions of f-Hb were generated for all participants, all men and women, and men and women by age quintile and deprivation quintile. Distributions were also generated by geographical region for all participants, men and women, and by deprivation. Comparisons of f-Hb distributions with those found in a pilot evaluation of FIT and three other countries were performed. Results: f-Hb was documented for 887,248 screening participants, 422,385 men and 464,863 women. f-Hb varied by sex, age, deprivation quintile and geographical region. The f-Hb distributions by sex and age differed between the SBoSP and the pilot evaluation and the three other countries. Conclusions: f-Hb is higher in men than in women and increases with age and deprivation in both sexes. f-Hb also varies by geographical region, independently of deprivation, and by country. The f-Hb distribution estimated by pilot evaluation may not represent the population distribution. Decision limits have advantages over reference intervals. Use of partitioned f-Hb thresholds for further investigation, based on the data generated, has advantages and disadvantages, as do risk scores based on a spectrum of influencing variables. [ABSTRACT FROM AUTHOR]

This editorial compares the situation for postcolonial scholars in 1998, when the journal started, with that of twenty years later in 2018, and notes that Interventions’ original statement of the scope and direction of the journal remains relevant in the changed conditions of the twenty-first century even if, inevitably, the issues need to be redefined and rearticulated for today. [ABSTRACT FROM PUBLISHER]

Objective: This study aimed to examine the effect of perceived diagnostic delay on cancer-related distress and determine whether fear of cancer-recurrence and quality of life mediate this relationship.Methods: Cross-sectional study in which 311 colorectal cancer (CRC) survivors in Scotland completed a survey, which included questions on cancer-related distress (IES-R), perceived diagnostic delay, quality of life (trial outcome index of the FACT-C: FACT-C TOI) and fear of cancer recurrence. Fifteen patients withheld consent to data matching with medical records, leaving a sample size of 296. Participants were an average of 69 years old (range 56 to 81) and between 3.5 and 12 years post-diagnosis. Multiple regressions were used to test predictors of distress and regression and bootstrapping to test for mediation.Results: Perceived diagnostic delay was correlated with higher cancer-related distress, while objective markers of diagnostic delay (disease stage at diagnosis and treatment received) were not. Some of the relationship between perceived diagnostic delay and cancer-related distress was mediated by quality of life, but not by fear of cancer recurrence.Conclusions: Perceived diagnostic delay was associated with higher cancer-related distress among CRC survivors. While poorer quality of life partly explained such associations, fear of cancer recurrence, stage at diagnosis and treatment did not. The exact features of diagnostic delay that are associated with cancer-related distress remain unclear. Future research should examine the experiences patients go through prior to diagnosis that may increase distress, in an effort to improve our understanding of the factors affecting emotional wellbeing among CRC survivors. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We investigated in vitro the potential mutagenic and toxic effects of two clay-based nanoparticles, Cloisite® Na+ (Cloisite) and halloysite; and multi-walled carbon nanotubes (MWCNT), commonly used in the polymer composite industry. Using the Ames test, the three nanoparticles did not have a true mutagenic effect, although growth of Salmonella enterica var. Typhimurium ( S.typhimurium) was diminished at higher nanoparticle concentrations. We investigated the impact of nanoparticles on Escherichia coli and S. typhimurium including oxyR and rpoS mutants, which are susceptible to oxidative stress. The oxyR mutants were inhibited in the presence of nanoparticles, when grown aerobically with light. Toxicity was not observed in the absence of light or during anaerobic growth. E. coli rpoS mutants exhibited some toxicity when cultured with Cloisite and MWCNT only when grown aerobically with light. There was no effect with other nanoparticles, or with S. typhimurium rpoS mutants. MWCNT exhibited a slight toxic effect against Epithelioma papulosum cyprini (EPC) cells only at the highest concentration tested. There was no discernable toxicity to EPC cells caused by the clay nanoparticles. We conclude that clay-based nanoparticles and MWCNT do not exert a mutagenic effect and do not have a general toxic effect across all bacterial species or between prokaryotic and eukaryotic cells. Modest toxicity was only observed in eukaryotic EPC cells against MWCNT at the highest concentration tested. Limited species-specific toxicity to clay based and MWCNT nanoparticles was seen in bacterial strains primarily due to culture conditions and mutations that exacerbate oxidative stress. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 961-968, 2014. [ABSTRACT FROM AUTHOR]

Background: Faecal immunochemical tests (FIT) are becoming widely used in colorectal cancer screening. Estimation of faecal haemoglobin concentration in a large group prompted an observational study on gender and age. Methods: A single estimate of faecal haemoglobin concentration was made using quantitative automated immunoturbidimetry. Potential reference intervals were calculated for men and women and for age quintiles according to the Clinical and Laboratory Standards Institute Approved Guideline. The percentages of positive results were calculated at a number of concentrations. The percentages of individuals who fell into different risk groups were assessed. Results: The 97.5 percentiles, potential upper reference limits, were 519 ng haemoglobin/mL (90% CI: 468-575) for men and 283 ng haemoglobin/mL (90% CI: 257-316) for women. Concentrations increased with age in both genders. Decision limits have advantages over reference intervals. At any cut-off concentration, more men are declared positive than women and more older people are declared positive than younger people. Future risk of neoplasia is higher in men than in women and in older people. Conclusions: Faecal haemoglobin concentrations vary with gender and age. More tailored strategies are needed in screening programmes. Faecal haemoglobin concentration could be included in individual risk assessment scores. These data should assist in screening programme design. [ABSTRACT FROM AUTHOR]

RNA pseudoknots are structural elements found in almost all classes of RNA. Pseudoknots form when a single-stranded region in the loop of a hairpin base-pairs with a stretch of complementary nucleotides elsewhere in the RNA chain. This simple folding strategy is capable of generating a large number of stable three-dimensional folds that display a diverse range of highly specific functions in a variety of biological processes. The present review focuses on pseudoknots that act in the regulation of protein synthesis using cellular and viral examples to illustrate their versatility. Emphasis is placed on structurally well-defined pseudoknots that play a role in internal ribosome entry, autoregulation of initiation, ribosomal frameshifting during elongation and trans-translation. [ABSTRACT FROM AUTHOR]

High-resolution structures have given an extremely detailed view of aspects of ribosomes, including some near-functional states. Here, we review the importance of cryo-electron microscopy, among other techniques, in giving an understanding of the higher dynamics of the ribosome accompanying active recruitment of mRNA to the small subunit and translocation of tRNAs. Recent data show that careful use of a variety of different techniques is necessary for a proper understanding of the basis of function in systems such as the ribosome. [ABSTRACT FROM AUTHOR]

The murine molecule dectin-1 (known as the β-glucan receptor in humans) is an immune cell surface receptor implicated in the immunological defense against fungal pathogens. Sequence analysis has indicated that the dectin-1 extracellular domain is a C-type lectin-like domain, and functional studies have established that it binds fungal β-glucans. We report several dectin-1 crystal structures, including a high-resolution structure and a 2.8 Å resolution structure in which a short soaked natural β-glucan is trapped in the crystal lattice. In vitro characterization of dectin-1 in the presence of its natural ligand indicates higher-order complex formation between dectin-1 and β-glucans. These combined structural and biophysical data considerably extend the current knowledge of dectin-1 structure and function, and suggest potential mechanisms of defense against fungal pathogens. [ABSTRACT FROM AUTHOR]

This article analyses the ways in which Richard Hoggart, in The Uses of Literacy, evokes the class nuances of the working-class culture of his childhood while deprecating the popular culture of his own day. It is argued that despite his judgemental attitude, his literary evocation of the contemporary popular culture that he dislikes leaps to life in a manner comparable to Joyce's Ulysses and overpowers his arguments against it. [ABSTRACT FROM AUTHOR]

Although an ileoanal pouch is frequently offered to patients with ulcerative colitis, it is still not clear to what extent this operation offers advantages over a permanent ileostomy. The aim of this study was to determine whether patients with a pouch have less morbidity and a better quality of life than a matched group of patients with a Brooke ileostomy. Nineteen patients (12 males and 7 females, median age 41 years) who had undergone total colectomy and ileoanal pouch formation for ulcerative colitis were individually matched with patients who had had a panproctocolectomy and ileostomy; patients were matched for disease process, sex, age, socioeconomic status, and time since surgery. Quality of life was assessed using the Short-Form 36 version 2 questionnaire, the inflammatory bowel disease questionnaire, and a few additional questions on perception of body image. The scores were compared using the nonparametric Wilcoxon signed-rank test for paired samples. The number and type of postoperative complications, as well as the number of operative stages, were recorded prospectively. Restorative proctocolectomy was associated with a significantly better perception of body image than a permanent stoma, although quality of life in general was similar in both groups. Patients with a pouch had more long-term complications than patients with an ileostomy within the same period of time (52.6% vs. 26.3%). The median number of stages for pouch construction was two, compared to a median of one stage for an ileostomy (P<0.0001). Because of the high long-term complication rate and the relatively small quality-of-life advantage associated with restorative proctocolectomy, patients need to be counseled thoroughly before agreeing to this operation. [Copyright &y& Elsevier]

Provides a critical review of the estimation of frequency correlation functions (FCF) using channel impulse response estimates derived from propagation measurements. Derivation of FCF from channel impulse response functions; Analysis of data measured on fading mobile radio channels; FCF estimates for a Rayleigh and Rician fading channel.

Examines the effect of mutated adenomatous polyposis coli, Kirsten-ras and p53 on the emergence of colorectal cancer. Details of the genetic pathways of colorectal cancer; Symptoms and diagnosis of colorectal cancer; Characterization of the tumor mutation spectra.

In order to see whether the stringent response was involved in biofilm formation, Escherichia coli DS291 (MG1655), and its isogenic relA spoT derivative were grown for 48 h in a chemostat at dilution rates of 0.025 and 0.25 h[sup –1] under serine limitation. The absence of the stringent response genes relA and spoT had little effect on the planktonic cell concentrations. However, a significant (P < 0.001) reduction in biofilm cell density of the relA spoT mutants was seen at a doubling time of 40 h. At a doubling time of 4 h, differences in biofilm cell density were not significant. Scanning confocal laser microscopy demonstrated the cell densities of microcolonies in the relA spoT mutant to be lower than those in the wild type. Using a microtiter plate assay, we found biofilm formation in relA spoT mutants to be similarly reduced in minimal media but to be enhanced in rich media (Luria–Bertani broth). No significant differences in biofilm formation were observed between wild type and isogenic relA mutants under any growth conditions. Overall, these results suggest that both stringent response genes relA and spoT are important in nutrient-limited biofilms. Key words: biofilm, stringent response, nutrient limitation, microcolony, Escherichia coli.Pour vérifier si la réponse stricte était impliquée dans la formation du biofilm, l'Escherichia coli DS291 (MG1655) et son dérivé isogénique relA spoT ont été cultivés pendant 48 h dans un chémostat à des dilutions de 0,025 et 0,25 h[sup –1] dans des conditions limitées en sérine. L'absence des gènes de la réponse stricte relA et spoT avait peu d'effet sur les concentrations de cellules planctoniques. Par contre, une diminution significative (P < 0,001) de la densité en cellules du biofilm des mutants relA spoT a été observée avec un temps de génération de 40 h. Avec un temps de génération de 4 h, les différences dans la densité cellulaire du biofilm n'étaient pas significatives. La microscopie confocale au laser a révélé que les densités en cellules des microcolonies avec le mutant relA spoT étaient plus basses qu'avec le type sauvage. Lors d'essais faits dans des plaques à microtitration, nous avons observé que la formation du biofilm avec les mutants relA spoT était réduite de la même façon dans des milieux minimaux mais augmentée dans les milieux riches (bouillon Luria–Bertani). Il n'y avait pas de différence significative dans la formation du biofilm entre la souche sauvage et les mutants isogéniques relA dans chacune des conditions de croissance. Globalement, ces résultats suggèrent que les deux gènes de la réponse stricte relA etspoT sont importants dans les biofilms limités en nutriments.Mots clés : biofilm, réponse stricte, limitation en nutriments, microcolonie, Escherichia coli.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Reports an examination of potential advantages of cell-site diversity with selection combining in the context of millimeter-wave fixed cellular systems. Radar measurements and radio link simulation; Angular correlation; Modeling for prediction of cell-site diversity gain.

Examines the effects of community composition, growth rate and susceptibility of aquifer biofilm bacteria on betadine disinfection. Evaluation on biofilm formation and resistance to iodine disinfectant betadine; Increase in biolfilm population size with increasing species diversity; Influences of community composition, growth rate and betadine concentration on biofilm formation and betadine resistance.

Offers information on the measurement and analysis of wideband propagation data for indoor radio channels at 40 GHz. Methodology used to gather the information; Reference made to wired indoor communications systems; Summarization of the results.

Argues that closed-form equations can be used to calculate error rates for differential quadrature phase-shift keying (DQPSK). Information on the results which are quantitative and free from uncertainties; Problem associated with predicting the probability of error on fading digital communications channels; Details on the study.

Presents several correspondence related to medical issues in Great Britain. Demonstration of circulating immune complexes in schistosomiasis; Efficacy of penicillamine in treating myasthenia gravis; Tendencies of television to depict care for mentally handicapped problems.

Discusses the screening of colorectal cancer among high-risk groups. Aims of high-risk group surveillance; Population screening; Psychological effects of screening.

1-anilino-8-naphtalenesulfonate (ANS) is a hydrophobic dipole previously used to demonstrate that the proton for potassium exchange by the gastric HK-ATPase is electroneutral. In this paper, we demonstrate that ANS binds to gastric membranes and probes conformational changes of the HK-ATPase independently of any active H for K exchange. Conformational changes require the presence of potassium-valinomycin and are not triggered by sodium. Potassium effect is enhanced by ATP, in the presence and in the absence of magnesium and, by ADP, in the presence of magnesium. Labeling of the pig HK-ATPase K518 by fluorescein-5-isothiocyanate inhibits the enzyme activity and knocks out the ATP effect on ANS fluorescence. Scherring 28080 and the monoclonal antibody 95-111, two competitive inhibitors of K-activated ATPase dephosphorylation, do not modify K-effect on ANS fluorescence but inhibit ATP effects. This supports that ANS does not probe K-site between the H1-H2 loop. Treatment of gastric membranes with trypsin does not inhibit the ANS response to potassium but does inhibit the response to ATP. This suggests that the ATP site inducing the ANS response is cytoplasmic and the potassium site is intramembranous. Titration reveals that one mole of ANS interacts with one mole of ATPase. We suggest that ANS probes a hydrophobic potassium site of gastric ATPase and that addition of ATP and ADP-Mg embed that site. [ABSTRACT FROM AUTHOR]

Discusses the efficiency of enjoining a defendant from dealing with his or her assets during the pendency of litigation so that the risk of a dry judgment for the plaintiff is minimized. Inconsistent assessment of applications for such injunctions by English, Canadian and American courts; How foregone gains are valued less than losses; Risk of an erroneous decision.

Reproduced from Robert J.C. Young, Torn Halves (Manchester Manchester University Press, 1996). Pages: 256. ISBN: 0–7190–477–3 (pbk); 0–7190–4776–5 (hbk). Price: £14.99 (pbk); £40.00 (hbk). [ABSTRACT FROM PUBLISHER]

Describes a teaching strategy employed in a senior-level microbiology course where students engage in original research projects. Examples of several student projects; Impact on students.

Reports a simple laboratory exercise that demonstrates the ability of a latex glove to act as a barrier against bacterial or viral transmission. Testing the ability of gloves to block bacterial transmission; Illustration on the importance of using sterile gloves; Safety issues concerning the manipulation of microorganisms.