Evaluation of the North West London Diabetes Foot Care Transformation Project: a mixed-methods evaluation

Introduction: Diabetes foot ulceration (DFU) presents an enormous burden to those living with diabetes and to the local health systems and economies. There is an increasing interest in implementing integrated care models to enhance the quality of care for people living with diabetes and related complications and the value of co-production approaches to achieve sustainable change. This paper aims to describe the evaluation methodology for the North West London (NWL) Diabetes Foot Care Transformation project. Description: A mixed methods design including: i) a quasi-experimental quantitative analysis assessing the impact of the implementation of the local secondary care multi-disciplinary diabetes foot team clinics on service utilisation and clinical outcomes (amputations and number of healed patients); ii) a phenomenological, qualitative study to explore patient and staff experience; and iii) a within-trial cost-effectiveness analysis (pre and post 2017) to evaluate the programme cost-effectiveness. Discussion and Conclusion: Demonstrating the impact of multidisciplinary, integrated care models and the value of co-production approaches is important for health providers and commissioners trying to improve health outcome. Evaluation is also needed to identify strategies to overcome barriers which might have reduced the impact of the programme and key elements for improvement

TELEMAC model archive: Integrating open–source tools for the management and visualisation of model data

Water Qualit

Transient heterogeneity in extracellular protease production by Bacillus subtilis

The most sophisticated survival strategy Bacillus subtilis employs is the differentiation of a subpopulation of cells into highly resistant endospores. To examine the expression patterns of non-sporulating cells within heterogeneous populations, we used buoyant density centrifugation to separate vegetative cells from endospore-containing cells and compared the transcriptome profiles of both subpopulations. This demonstrated the differential expression of various regulons. Subsequent single-cell analyses using promoter-gfp fusions confirmed our microarray results. Surprisingly, only part of the vegetative subpopulation highly and transiently expresses genes encoding the extracellular proteases Bpr (bacillopeptidase) and AprE (subtilisin), both of which are under the control of the DegU transcriptional regulator. As these proteases and their degradation products freely diffuse within the liquid growth medium, all cells within the clonal population are expected to benefit from their activities, suggesting that B. subtilis employs cooperative or even altruistic behavior. To unravel the mechanisms by which protease production heterogeneity within the non-sporulating subpopulation is established, we performed a series of genetic experiments combined with mathematical modeling. Simulations with our model yield valuable insights into how population heterogeneity may arise by the relatively long and variable response times within the DegU autoactivating pathway

Elastic and inelastic light scattering from single bacterial spores in an optical trap allows the monitoring of spore germination dynamics

Raman scattering spectroscopy and elastic light scattering intensity (ESLI) were used to simultaneously measure levels of Ca-dipicolinic acid (CaDPA) and changes in spore morphology and refractive index during germination of individual B. subtilis spores with and without the two redundant enzymes (CLEs), CwlJ and SleB, that degrade sporesâ peptidoglycan cortex. Conclusions from these measurements include: 1) CaDPA release from individual wild-type germinating spores was biphasic; in a first heterogeneous slow phase, Tlag, CaDPA levels decreased â ¼15% and in the second phase ending at Trelease, remaining CaDPA was released rapidly; 2) in L-alanine germination of wild-type spores and spores lacking SleB: a) the ESLI rose â ¼2-fold shortly before Tlag at T1; b) following Tlag, the ESLI again rose â ¼2-fold at T2 when CaDPA levels had decreased â ¼50%; and c) the ESLI reached its maximum value at â ¼Trelease and then decreased; 3) in CaDPA germination of wild-type spores: a) Tlag increased and the first increase in ESLI occurred well before Tlag, consistent with different pathways for CaDPA and L-alanine germination; b) at Trelease the ESLI again reached its maximum value; 4) in L-alanine germination of spores lacking both CLEs and unable to degrade their cortex, the time Î Trelease (Treleaseâ Tlag) for excretion of â ¥75% of CaDPA was â ¼15-fold higher than that for wild-type or sleB spores; and 5) spores lacking only CwlJ exhibited a similar, but not identical ESLI pattern during L-alanine germination to that seen with cwlJ sleB spores, and the high value for Î Trelease. Originally published Analytical Chemistry, Vol. 81, No. 10, May 200

Leptospira seroprevalence and associations between seropositivity, clinical disease and host factors in horses

<p>Abstract</p> <p>Background</p> <p>A cross-sectional study was carried out to determine the seroprevalence of different serovars of <it>Leptospira </it>spp. and their association with clinical disease and host factors in Swedish horses.</p> <p>Methods</p> <p>Sera from 2017 horses brought to equine clinics during 1997–98 were investigated. The sera were examined by microscopic agglutination test for the presence of antibodies against the following <it>L. interrogans </it>serovars: Bratislava strain Jez, Icterohaemorrhagiae strain Kantorowicz and Pomona strain Pomona and also <it>L. kirschneri </it>sv Grippotyphosa strain Duyster and <it>L. borgpetersenii </it>sv Sejroe strain M 84. Host factors, disease factors, season, pasture access and outdoor confinement variables were analysed with respect to seropositivity to sv Bratislava and Icterohaemorrhagiae. Multivariable logistic regression was used to model seropositivity to sv Bratislava and Icterohaemorrhagiae (seroprevalence > 8%).</p> <p>Results</p> <p>The seroprevalence, at a cut-off 1:100, were for sv Bratislava (16.6%), Icterohaemorrhagiae (8.3%), Sejroe (1.2%), Pomona (0.5%) and Grippotyphosa (0.4%). In the multivariable analysis, it was demonstrated that seroprevalence increased with age for sv Bratislava and Icterohaemorrhagiae. For sv Bratislava the seasons April – June and October – December and for sv Icterohaemorrhagiae October – December had higher seroprevalences than other seasons. Horses not used for racing had higher levels of seropositivity to sv Bratislava. Furthermore, horses with respiratory problems as well as horses with fatigue had higher levels of seropositivity to sv Bratislava. Ponies and coldbloods, and horses with access to pasture, had lower seroprevalence for sv Icterohaemorrhagiae. Healthy horses had lower seroprevalence for sv Icterohaemorrhagiae, than non-healthy horses.</p> <p>Conclusion</p> <p>There was no significant association between clinical signs and disease and positive titres to sv Bratislava (except for the association between respiratory problems and fatigue and seropositivity to sv Bratislava). The results suggest that horses with increasing age and exposed to factors associated with outdoor life had an increased seroprevalence for sv Bratislava, indicating that horses get infected from outdoor and/or are exposed to shedding from other horses (management dependent). For sv Icterohaemorrhagiae, management possibly plays a role as ponies and coldbloods as well as healthy horses had lower seroprevalence. Overall, the age of the horse should be taken into consideration when evaluating the titre as the average healthy horse has a higher titre than a young horse.</p

Fluctuations in spo0A Transcription Control Rare Developmental Transitions in Bacillus subtilis

Phosphorylated Spo0A is a master regulator of stationary phase development in the model bacterium Bacillus subtilis, controlling the formation of spores, biofilms, and cells competent for transformation. We have monitored the rate of transcription of the spo0A gene during growth in sporulation medium using promoter fusions to firefly luciferase. This rate increases sharply during transient diauxie-like pauses in growth rate and then declines as growth resumes. In contrast, the rate of transcription of an rRNA gene decreases and increases in parallel with the growth rate, as expected for stable RNA synthesis. The growth pause-dependent bursts of spo0A transcription, which reflect the activity of the spo0A vegetative promoter, are largely independent of all known regulators of spo0A transcription. Evidence is offered in support of a “passive regulation” model in which RNA polymerase stops transcribing rRNA genes during growth pauses, thus becoming available for the transcription of spo0A. We show that the bursts are followed by the production of phosphorylated Spo0A, and we propose that they represent initial responses to stress that bring the average cell closer to the thresholds for transition to bimodally expressed developmental responses. Measurement of the numbers of cells expressing a competence marker before and after the bursts supports this hypothesis. In the absence of ppGpp, the increase in spo0A transcription that accompanies the entrance to stationary phase is delayed and sporulation is markedly diminished. In spite of this, our data contradicts the hypothesis that sporulation is initiated when a ppGpp-induced depression of the GTP pool relieves repression by CodY. We suggest that, while the programmed induction of sporulation that occurs in stationary phase is apparently provoked by increased flux through the phosphorelay, bet-hedging stochastic transitions to at least competence are induced by bursts in transcription

Anti-infectives in Drug Delivery-Overcoming the Gram-Negative Bacterial Cell Envelope.

Infectious diseases are becoming a major menace to the state of health worldwide, with difficulties in effective treatment especially of nosocomial infections caused by Gram-negative bacteria being increasingly reported. Inadequate permeation of anti-infectives into or across the Gram-negative bacterial cell envelope, due to its intrinsic barrier function as well as barrier enhancement mediated by resistance mechanisms, can be identified as one of the major reasons for insufficient therapeutic effects. Several in vitro, in silico, and in cellulo models are currently employed to increase the knowledge of anti-infective transport processes into or across the bacterial cell envelope; however, all such models exhibit drawbacks or have limitations with respect to the information they are able to provide. Thus, new approaches which allow for more comprehensive characterization of anti-infective permeation processes (and as such, would be usable as screening methods in early drug discovery and development) are desperately needed. Furthermore, delivery methods or technologies capable of enhancing anti-infective permeation into or across the bacterial cell envelope are required. In this respect, particle-based carrier systems have already been shown to provide the opportunity to overcome compound-related difficulties and allow for targeted delivery. In addition, formulations combining efflux pump inhibitors or antimicrobial peptides with anti-infectives show promise in the restoration of antibiotic activity in resistant bacterial strains. Despite considerable progress in this field however, the design of carriers to specifically enhance transport across the bacterial envelope or to target difficult-to-treat (e.g., intracellular) infections remains an urgently needed area of improvement. What follows is a summary and evaluation of the state of the art of both bacterial permeation models and advanced anti-infective formulation strategies, together with an outlook for future directions in these fields

The genetic organisation of prokaryotic two-component system signalling pathways

<p>Abstract</p> <p>Background</p> <p>Two-component systems (TCSs) are modular and diverse signalling pathways, involving a stimulus-responsive transfer of phosphoryl groups from transmitter to partner receiver domains. TCS gene and domain organisation are both potentially informative regarding biological function, interaction partnerships and molecular mechanisms. However, there is currently little understanding of the relationships between domain architecture, gene organisation and TCS pathway structure.</p> <p>Results</p> <p>Here we classify the gene and domain organisation of TCS gene loci from 1405 prokaryotic replicons (>40,000 TCS proteins). We find that 200 bp is the most appropriate distance cut-off for defining whether two TCS genes are functionally linked. More than 90% of all TCS gene loci encode just one or two transmitter and/or receiver domains, however numerous other geometries exist, often with large numbers of encoded TCS domains. Such information provides insights into the distribution of TCS domains between genes, and within genes. As expected, the organisation of TCS genes and domains is affected by phylogeny, and plasmid-encoded TCS exhibit differences in organisation from their chromosomally-encoded counterparts.</p> <p>Conclusions</p> <p>We provide here an overview of the genomic and genetic organisation of TCS domains, as a resource for further research. We also propose novel metrics that build upon TCS gene/domain organisation data and allow comparisons between genomic complements of TCSs. In particular, '<it>percentage orphaned TCS genes</it>' (or 'Dissemination') and '<it>percentage of complex loci</it>' (or 'Sophistication') appear to be useful discriminators, and to reflect mechanistic aspects of TCS organisation not captured by existing metrics.</p