High-throughput, fluorescent-aptamer-based measurements of steady-state transcription rates for the Mycobacterium tuberculosis RNA polymerase.

The first step in gene expression is the transcription of DNA sequences into RNA. Regulation at the level of transcription leads to changes in steady-state concentrations of RNA transcripts, affecting the flux of downstream functions and ultimately cellular phenotypes. Changes in transcript levels are routinely followed in cellular contexts via genome-wide sequencing techniques. However, in vitro mechanistic studies of transcription have lagged with respect to throughput. Here, we describe the use of a real-time, fluorescent-aptamer-based method to quantitate steady-state transcription rates of the Mycobacterium tuberculosis RNA polymerase. We present clear controls to show that the assay specifically reports on promoter-dependent, full-length RNA transcription rates that are in good agreement with the kinetics determined by gel-resolved, α-32P NTP incorporation experiments. We illustrate how the time-dependent changes in fluorescence can be used to measure regulatory effects of nucleotide concentrations and identity, RNAP and DNA concentrations, transcription factors, and antibiotics. Our data showcase the ability to easily perform hundreds of parallel steady-state measurements across varying conditions with high precision and reproducibility to facilitate the study of the molecular mechanisms of bacterial transcription.

Mycobacterium tuberculosis DNA repair helicase UvrD1 is activated by redox-dependent dimerization via a 2B domain cysteine.

Mycobacterium tuberculosis (Mtb) causes tuberculosis and, during infection, is exposed to reactive oxygen species and reactive nitrogen intermediates from the host immune response that can cause DNA damage. UvrD-like proteins are involved in DNA repair and replication and belong to the SF1 family of DNA helicases that use ATP hydrolysis to catalyze DNA unwinding. In Mtb, there are two UvrD-like enzymes, where UvrD1 is most closely related to other family members. Previous studies have suggested that UvrD1 is exclusively monomeric; however, it is well known that Escherichia coli UvrD and other UvrD family members exhibit monomer-dimer equilibria and unwind as dimers in the absence of accessory factors. Here, we reconcile these incongruent studies by showing that Mtb UvrD1 exists in monomer, dimer, and higher-order oligomeric forms, where dimerization is regulated by redox potential. We identify a 2B domain cysteine, conserved in many Actinobacteria, that underlies this effect. We also show that UvrD1 DNA-unwinding activity correlates specifically with the dimer population and is thus titrated directly via increasing positive (i.e., oxidative) redox potential. Consistent with the regulatory role of the 2B domain and the dimerization-based activation of DNA unwinding in UvrD family helicases, these results suggest that UvrD1 is activated under oxidizing conditions when it may be needed to respond to DNA damage during infection.

Molecular dissection of RbpA-mediated regulation of fidaxomicin sensitivity in mycobacteria.

RNA polymerase (RNAP) binding protein A (RbpA) is essential for mycobacterial viability and regulates transcription initiation by increasing the stability of the RNAP-promoter open complex (RPo). RbpA consists of four domains: an N-terminal tail (NTT), a core domain (CD), a basic linker, and a sigma interaction domain. We have previously shown that truncation of the RbpA NTT and CD increases RPo stabilization by RbpA, implying that these domains inhibit this activity of RbpA. Previously published structural studies showed that the NTT and CD are positioned near multiple RNAP-σA holoenzyme functional domains and predict that the RbpA NTT contributes specific amino acids to the binding site of the antibiotic fidaxomicin (Fdx), which inhibits the formation of the RPo complex. Furthermore, deletion of the NTT results in decreased Mycobacterium smegmatis sensitivity to Fdx, but whether this is caused by a loss in Fdx binding is unknown. We generated a panel of rbpA mutants and found that the RbpA NTT residues predicted to directly interact with Fdx are partially responsible for RbpA-dependent Fdx activity in vitro, while multiple additional RbpA domains contribute to Fdx activity in vivo. Specifically, our results suggest that the RPo-stabilizing activity of RbpA decreases Fdx activity in vivo. In support of the association between RPo stability and Fdx activity, we find that another factor that promotes RPo stability in bacteria, CarD, also impacts to Fdx sensitivity. Our findings highlight how RbpA and other factors may influence RNAP dynamics to affect Fdx sensitivity.

Biosensing Tacrolimus in Human Whole Blood by Using a Drug Receptor Fused to the Emerald Green Fluorescent Protein.

Tacrolimus (FK506) is an immunosuppressant drug (ISD) used to prevent organ rejection after transplantation that exhibits a narrow therapeutic window and is subject to wide inter- and intra-individual pharmacokinetic fluctuations requiring careful monitoring. The immunosuppressive capacity of FK506 arises from the formation of a complex with immunophilin FKBP1A. This paper describes the use of FKBP1A as an alternative to common antibodies for biosensing purposes. Bioassays use recombinant FKBP1A fused to the emerald green fluorescent protein (FKBP1A-EmGFP). Samples containing the immunosuppressant are incubated with the recombinant protein, and free FKBP1A-EmGFP is captured by magnetic beads functionalized with FK506 to generate a fluorescence signal. Recombinant receptor-drug interaction is evaluated by using a quartz crystal microbalance and nuclear magnetic resonance. The limit of detection (3 ng mL-1) and dynamic range thus obtained (5-70 ng mL-1) fulfill therapeutic requirements. The assay is selective for other ISD usually coadministered with FK506 and allows the drug to be determined in human whole blood samples from organ transplant patients with results comparing favorably with those of an external laboratory.

CarD and RbpA modify the kinetics of initial transcription and slow promoter escape of the Mycobacterium tuberculosis RNA polymerase.

The pathogen Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, enacts unique transcriptional regulatory mechanisms when subjected to host-derived stresses. Initiation of transcription by the Mycobacterial RNA polymerase (RNAP) has previously been shown to exhibit different open complex kinetics and stabilities relative to Escherichia coli (Eco) RNAP. However, transcription initiation rates also depend on the kinetics following open complex formation such as initial nucleotide incorporation and subsequent promoter escape. Here, using a real-time fluorescence assay, we present the first in-depth kinetic analysis of initial transcription and promoter escape for the Mtb RNAP. We show that in relation to Eco RNAP, Mtb displays slower initial nucleotide incorporation but faster overall promoter escape kinetics on the Mtb rrnAP3 promoter. Furthermore, in the context of the essential transcription factors CarD and RbpA, Mtb promoter escape is slowed via differential effects on initially transcribing complexes. Finally, based on their ability to increase the rate of open complex formation and decrease the rate of promoter escape, we suggest that CarD and RbpA are capable of activation or repression depending on the rate-limiting step of a given promoter's basal initiation kinetics.

Exploring mechanisms that explain how coalition groups are formed and how they work to sustain political priority for maternal and child health in Nigeria using the advocacy coalition framework.

BACKGROUND: The unacceptably high rate of maternal and child mortality in Nigeria prompted the government to introduce a free maternal and child health (MCH) programme, which was stopped abruptly following a change in government. This triggered increased advocacy for sustaining MCH as a political priority in the country and led to the formation of advocacy coalitions. This study set out to explain the process involved in the formation of advocacy coalition groups and how they work to bring about sustained political prioritization for MCH in Nigeria. It will contribute to the understanding of the Nigerian MCH sector subsystem and will be beneficial to health policy advocates and public health researchers in Nigeria. METHODS: This study employed a qualitative case study approach. Data were collected using a pretested interview guide to conduct 22 in-depth interviews, while advocacy events were reviewed pro forma. The document review was analysed using the manual content analysis method, while qualitative data audiotapes were transcribed verbatim, anonymized, double-coded in MS Word using colour-coded highlights and analysed using manual thematic and framework analysis guided by the advocacy coalition framework (ACF). The ACF was used to identify the policy subsystem including the actors, their belief, coordination and resources, as well as the effects of advocacy groups on policy change. Ethics and consent approval were obtained for the study. RESULTS: The policy subsystem identified the actors and characterized the coalitions, and described their group formation processes and resources/strategies for engagement. The perceived deep core belief driving the MCH agenda is the right of an individual to health. The effects of advocacy groups on policy change were identified, along with the factors that enabled effectiveness, as well as constraints to coalition formation. External factors and triggers of coalition formation were identified to include high maternal mortality and withdrawal of the free MCH programme, while the contextual issues were the health system issues and the socioeconomic factors affecting the country. CONCLUSION: Our findings add to an increasing body of evidence that the use of ACF is beneficial in exploring how advocacy coalitions are formed and in identifying the effects of advocacy groups on policy change.

Fluorinated Carbohydrates as Lectin Ligands: Simultaneous Screening of a Monosaccharide Library and Chemical Mapping by 19F NMR Spectroscopy.

Molecular recognition of carbohydrates is a key step in essential biological processes. Carbohydrate receptors can distinguish monosaccharides even if they only differ in a single aspect of the orientation of the hydroxyl groups or harbor subtle chemical modifications. Hydroxyl-by-fluorine substitution has proven its merits for chemically mapping the importance of hydroxyl groups in carbohydrate-receptor interactions. 19F NMR spectroscopy could thus be adapted to allow contact mapping together with screening in compound mixtures. Using a library of fluorinated glucose (Glc), mannose (Man), and galactose (Gal) derived by systematically exchanging every hydroxyl group by a fluorine atom, we developed a strategy combining chemical mapping and 19F NMR T2 filtering-based screening. By testing this strategy on the proof-of-principle level with a library of 13 fluorinated monosaccharides to a set of three carbohydrate receptors of diverse origin, i.e. the human macrophage galactose-type lectin, a plant lectin, Pisum sativum agglutinin, and the bacterial Gal-/Glc-binding protein from Escherichia coli, it became possible to simultaneously define their monosaccharide selectivity and identify the essential hydroxyls for interaction.

"If you are on duty, you may be afraid to come out to attend to a person": fear of crime and security challenges in maternal acute care in Nigeria from a realist perspective.

BACKGROUND: Maternal and Child Health is a global priority. Access and utilization of facility-based health services remain a challenge in low and middle-income countries. Evidence on barriers to providing and accessing services omits information on the role of security within facilities. This paper explores the role of security in the provision and use of maternal health services in primary healthcare facilities in Nigeria. METHODS: Study was carried out in Anambra state, Nigeria. Qualitative data were initially collected from 35 in-depth interviews and 24 focus groups with purposively identified key informants. Information gathered was used to build a programme theory that was tested with another round of interviews (17) and focus group (4) discussions. Data analysis and reporting were based on the Context-Mechanism-Outcome heuristic of Realist Evaluation methodology. RESULTS: The presence of a male security guard in the facility was the most important security factor that facilitated provision and uptake of services. Others include perimeter fencing, lighting and staff accommodation. Lack of these components constrained provision and use of services, by impacting on behaviour of staff and patients. Security concerns of facility staff who did not feel safe to let in people into unguarded facilities, mirrored those of pregnant women who did not utilize health facilities because of fear of not being let in and attended to by facility staff. CONCLUSION: Health facility security should be key consideration in programme planning, to avert staff and women's fear of crime which currently constrains provision and use of maternal healthcare at health facilities.

What makes advocacy work? Stakeholders' voices and insights from prioritisation of maternal and child health programme in Nigeria.

BACKGROUND: The Nigerian government introduced and implemented a health programme to improve maternal and child health (MCH) called Subsidy Reinvestment and Empowerment programme for MCH (SURE-P/MCH). It ran from 2012 and ended abruptly in 2015 and was followed by increased advocacy for sustaining the MCH (antenatal, delivery, postnatal and immunization) services as a policy priority. Advocacy is important in allowing social voice, facilitating prioritization, and bringing different forces/actors together. Therefore, the study set out to understand how advocacy works - through understanding what effective advocacy implementation processes comprise and what mechanisms are triggered by which contexts to produce the intended outcomes. METHODS: The study used a Realist Evaluation design through a mixed quantitative and qualitative methods case study approach. The programme theory (PT) was developed from three substantive social theories (power politics, media influence communication theory, and the three-streams theory of agenda-setting), data and programme design documentation, and subsequently tested. We report information from 22 key informant interviews including national and State policy and law makers, policy implementers, CSOs, Development partners, NGOs, health professional groups, and media practitioners and review of relevant documents on advocacy events post-SURE-P. RESULTS: Key advocacy organizations and individuals including health professional groups, the media, civil society organizations, powerful individuals, and policymakers were involved in advocacy activities. The nature of their engagement included organizing workshops, symposiums, town hall meetings, individual meetings, press conferences, demonstrations, and engagements with media. Effective advocacy mechanism involved alliance brokering to increase influence, the media supporting and engaging in advocacy, and the use of champions, influencers, and spouses (Leadership and Elite Gendered Power Dynamics). The key contextual influences which determined the effectiveness of advocacy measures for MCH included the political cycle, availability of evidence on the issue, networking with powerful and interested champions, and alliance building in advocacy. All these enhanced the entrenchment of MCH on the political and financial agenda at the State and Federal levels. CONCLUSIONS: Our result suggest that advocacy can be a useful tool to bring together different forces by allowing expression of voices and ensuring accountability of different actors including policymakers. In the context of poor health outcomes, interest from policymakers and politicians in MCH, combined with advocacy from key policy actors armed with evidence, can improve prioritization and sustained implementation of MCH services.

Domains within RbpA Serve Specific Functional Roles That Regulate the Expression of Distinct Mycobacterial Gene Subsets.

The RNA polymerase (RNAP) binding protein A (RbpA) contributes to the formation of stable RNAP-promoter open complexes (RPo) and is essential for viability in mycobacteria. Four domains have been identified in the RbpA protein, i.e., an N-terminal tail (NTT) that interacts with RNAP ß' and σ subunits, a core domain (CD) that contacts the RNAP ß' subunit, a basic linker (BL) that binds DNA, and a σ-interaction domain (SID) that binds group I and group II σ factors. Limited in vivo studies have been performed in mycobacteria, however, and how individual structural domains of RbpA contribute to RbpA function and mycobacterial gene expression remains mostly unknown. We investigated the roles of the RbpA structural domains in mycobacteria using a panel of rbpA mutants that target individual RbpA domains. The function of each RbpA domain was required for Mycobacterium tuberculosis viability and optimal growth in Mycobacterium smegmatis We determined that the RbpA SID is both necessary and sufficient for RbpA interaction with the RNAP, indicating that the primary functions of the NTT and CD are not solely association with the RNAP. We show that the RbpA BL and SID are required for RPo stabilization in vitro, while the NTT and CD antagonize this activity. Finally, RNA-sequencing analyses suggest that the NTT and CD broadly activate gene expression, whereas the BL and SID activate or repress gene expression in a gene-dependent manner for a subset of mycobacterial genes. Our findings highlight specific outcomes for the activities of the individual functional domains in RbpA.IMPORTANCEMycobacterium tuberculosis is the causative agent of tuberculosis and continues to be the most lethal infectious disease worldwide. Improved molecular understanding of the essential proteins involved in M. tuberculosis transcription, such as RbpA, could provide targets for much needed future therapeutic agents aimed at combatting this pathogen. In this study, we expand our understanding of RbpA by identifying the RbpA structural domains responsible for the interaction of RbpA with the RNAP and the effects of RbpA on transcription initiation and gene expression. These experiments expand our knowledge of RbpA while also broadening our understanding of bacterial transcription in general.

Cooperative stabilization of Mycobacterium tuberculosis rrnAP3 promoter open complexes by RbpA and CarD.

The essential mycobacterial transcriptional regulators RbpA and CarD act to modulate transcription by associating to the initiation complex and increasing the flux of transcript production. Each of these factors interacts directly with the promoter DNA template and with RNA polymerase (RNAP) holoenzyme. We recently reported on the energetics of CarD-mediated open complex stabilization on the Mycobacterium tuberculosis rrnAP3 ribosomal promoter using a stopped-flow fluorescence assay. Here, we apply this approach to RbpA and show that RbpA stabilizes RNAP-promoter open complexes (RPo) via a distinct mechanism from that of CarD. Furthermore, concentration-dependent stopped-flow experiments with both factors reveal positive linkage (cooperativity) between RbpA and CarD with regard to their ability to stabilize RPo The observation of positive linkage between RbpA and CarD demonstrates that the two factors can act on the same transcription initiation complex simultaneously. Lastly, with both factors present, the kinetics of open complex formation is significantly faster than in the presence of either factor alone and approaches that of E. coli RNAP on the same promoter. This work provides a quantitative framework for the molecular mechanisms of these two essential transcription factors and the critical roles they play in the biology and pathology of mycobacteria.

Effects of Increasing the Affinity of CarD for RNA Polymerase on Mycobacterium tuberculosis Growth, rRNA Transcription, and Virulence.

CarD is an essential RNA polymerase (RNAP) interacting protein in Mycobacterium tuberculosis that stimulates formation of RNAP-promoter open complexes. CarD plays a complex role in M. tuberculosis growth and virulence that is not fully understood. Therefore, to gain further insight into the role of CarD in M. tuberculosis growth and virulence, we determined the effect of increasing the affinity of CarD for RNAP. Using site-directed mutagenesis guided by crystal structures of CarD bound to RNAP, we identified amino acid substitutions that increase the affinity of CarD for RNAP. Using these substitutions, we show that increasing the affinity of CarD for RNAP increases the stability of the CarD protein in M. tuberculosis In addition, we show that increasing the affinity of CarD for RNAP increases the growth rate in M. tuberculosis without affecting 16S rRNA levels. We further show that increasing the affinity of CarD for RNAP reduces M. tuberculosis virulence in a mouse model of infection despite the improved growth rate in vitro Our findings suggest that the CarD-RNAP interaction protects CarD from proteolytic degradation in M. tuberculosis, establish that growth rate and rRNA levels can be uncoupled in M. tuberculosis and demonstrate that the strength of the CarD-RNAP interaction has been finely tuned to optimize virulence. IMPORTANCE: Mycobacterium tuberculosis, the causative agent of tuberculosis, remains a major global health problem. In order to develop new strategies to battle this pathogen, we must gain a better understanding of the molecular processes involved in its survival and pathogenesis. We have previously identified CarD as an essential transcriptional regulator in mycobacteria. In this study, we detail the effects of increasing the affinity of CarD for RNAP on transcriptional regulation, CarD protein stability, and virulence. These studies expand our understanding of the global transcription regulator CarD, provide insight into how CarD activity is regulated, and broaden our understanding of prokaryotic transcription.

CarD stabilizes mycobacterial open complexes via a two-tiered kinetic mechanism.

CarD is an essential and global transcriptional regulator in mycobacteria. While its biological role is unclear, CarD functions by interacting directly with RNA polymerase (RNAP) holoenzyme promoter complexes. Here, using a fluorescent reporter of open complex, we quantitate RPo formation in real time and show that Mycobacterium tuberculosis CarD has a dramatic effect on the energetics of RNAP bound complexes on the M. tuberculosis rrnAP3 ribosomal RNA promoter. The data reveal that Mycobacterium bovis RNAP exhibits an unstable RPo that is stabilized by CarD and suggest that CarD uses a two-tiered, concentration-dependent mechanism by associating with open and closed complexes with different affinities. Specifically, the kinetics of open-complex formation can be explained by a model where, at saturating concentrations of CarD, the rate of bubble collapse is slowed and the rate of opening is accelerated. The kinetics and open-complex stabilities of CarD mutants further clarify the roles played by the key residues W85, K90 and R25 previously shown to affect CarD-dependent gene regulation in vivo. In contrast to M. bovis RNAP, Escherichia coli RNAP efficiently forms RPo on rrnAP3, suggesting an important difference between the polymerases themselves and highlighting how transcriptional machinery can vary across bacterial genera.

Novel vaccines targeting dendritic cells by coupling allergoids to nonoxidized mannan enhance allergen uptake and induce functional regulatory T cells through programmed death ligand 1.

BACKGROUND: Allergen immunotherapy (AIT) is the only curative treatment for allergy. AIT faces pitfalls related to efficacy, security, duration, and patient compliance. Novel vaccines overcoming such inconveniences are in demand. OBJECTIVES: We sought to study the immunologic mechanisms of action for novel vaccines targeting dendritic cells (DCs) generated by coupling glutaraldehyde-polymerized grass pollen allergoids to nonoxidized mannan (PM) compared with glutaraldehyde-polymerized allergoids (P) or native grass pollen extracts (N). METHODS: Skin prick tests and basophil activation tests with N, P, or PM were performed in patients with grass pollen allergy. IgE-blocking experiments, flow cytometry, confocal microscopy, cocultures, suppression assays, real-time quantitative PCR, ELISAs, and ELISpot assays were performed to assess allergen capture by human DCs and T-cell responses. BALB/c mice were immunized with PM, N, or P. Antibody levels, cytokine production by splenocytes, and splenic forkhead box P3 (FOXP3)(+) regulatory T (Treg) cells were quantified. Experiments with oxidized PM were also performed. RESULTS: PM displays in vivo hypoallergenicity, induces potent blocking antibodies, and is captured by human DCs much more efficiently than N or P by mechanisms depending on mannose receptor- and dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin-mediated internalization. PM endorses human DCs to generate functional FOXP3(+) Treg cells through programmed death ligand 1. Immunization of mice with PM induces a shift to nonallergic responses and increases the frequency of splenic FOXP3(+) Treg cells. Mild oxidation impairs these effects in human subjects and mice, demonstrating the essential role of preserving the carbohydrate structure of mannan. CONCLUSIONS: Allergoids conjugated to nonoxidized mannan represent suitable vaccines for AIT. Our findings might also be of the utmost relevance to development of therapeutic interventions in other immune tolerance-related diseases.

RAMESES II reporting standards for realist evaluations.

BACKGROUND: Realist evaluation is increasingly used in health services and other fields of research and evaluation. No previous standards exist for reporting realist evaluations. This standard was developed as part of the RAMESES II project. The project's aim is to produce initial reporting standards for realist evaluations. METHODS: We purposively recruited a maximum variety sample of an international group of experts in realist evaluation to our online Delphi panel. Panel members came from a variety of disciplines, sectors and policy fields. We prepared the briefing materials for our Delphi panel by summarising the most recent literature on realist evaluations to identify how and why rigour had been demonstrated and where gaps in expertise and rigour were evident. We also drew on our collective experience as realist evaluators, in training and supporting realist evaluations, and on the RAMESES email list to help us develop the briefing materials. Through discussion within the project team, we developed a list of issues related to quality that needed to be addressed when carrying out realist evaluations. These were then shared with the panel members and their feedback was sought. Once the panel members had provided their feedback on our briefing materials, we constructed a set of items for potential inclusion in the reporting standards and circulated these online to panel members. Panel members were asked to rank each potential item twice on a 7-point Likert scale, once for relevance and once for validity. They were also encouraged to provide free text comments. RESULTS: We recruited 35 panel members from 27 organisations across six countries from nine different disciplines. Within three rounds our Delphi panel was able to reach consensus on 20 items that should be included in the reporting standards for realist evaluations. The overall response rates for all items for rounds 1, 2 and 3 were 94 %, 76 % and 80 %, respectively. CONCLUSION: These reporting standards for realist evaluations have been developed by drawing on a range of sources. We hope that these standards will lead to greater consistency and rigour of reporting and make realist evaluation reports more accessible, usable and helpful to different stakeholders.

Structural studies of novel glycoconjugates from polymerized allergens (allergoids) and mannans as allergy vaccines.

Immunotherapy for treating IgE-mediated allergies requires high doses of the corresponding allergen. This may result in undesired side effects and, to avoid them, hypoallergenic allergens (allergoids) polymerized with glutaraldehyde are commonly used. Targeting allergoids to dendritic cells to enhance cell uptake may result in a more effective immunotherapy. Allergoids coupled to yeast mannan, as source of polymannoses, would be suitable for this purpose, since mannose-binding receptors are expressed on these cells. Conventional conjugation procedures of mannan to proteins use oxidized mannan to release reactive aldehydes able to bind to free amino groups in the protein; yet, allergoids lack these latter because their previous treatment with glutaraldehyde. The aim of this study was to obtain allergoids conjugated to mannan by an alternative approach based on just glutaraldehyde treatment, taking advantage of the mannoprotein bound to the polymannose backbone. Allergoid-mannan glycoconjugates were produced in a single step by treating with glutaraldehyde a defined mixture of allergens derived from Phleum pratense grass pollen and native mannan (non-oxidized) from Saccharomyces cerevisae. Analytical and structural studies, including 2D-DOSY and (1)H-(13)C HSQC nuclear magnetic resonance spectra, demonstrated the feasibility of such an approach. The glycoconjugates obtained were polymers of high molecular weight showing a higher stability than the native allergen or the conventional allergoid without mannan. The allergoid-mannan glycoconjugates were hypoallergenic as detected by the IgE reactivity with sera from grass allergic patients, even with lower reactivity than conventional allergoid without mannan. Thus, stable hypoallergenic allergoids conjugated to mannan suitable for using in immunotherapy can be achieved using glutaraldehyde. In contrast to mannan oxidation, the glutaraldehyde approach allows to preserve mannoses with their native geometry, which may be functionally important for its receptor-mediated recognition.

CarD integrates three functional modules to promote efficient transcription, antibiotic tolerance, and pathogenesis in mycobacteria.

Although the basic mechanisms of prokaryotic transcription are conserved, it has become evident that some bacteria require additional factors to allow for efficient gene transcription. CarD is an RNA polymerase (RNAP)-binding protein conserved in numerous bacterial species and essential in mycobacteria. Despite the importance of CarD, its function at transcription complexes remains unclear. We have generated a panel of mutations that individually target three independent functional modules of CarD: the RNAP interaction domain, the DNA-binding domain, and a conserved tryptophan residue. We have dissected the roles of each functional module in CarD activity and built a model where each module contributes to stabilizing RNAP-promoter complexes. Our work highlights the requirement of all three modules of CarD in the obligate pathogen Mycobacterium tuberculosis, but not in Mycobacterium smegmatis. We also report divergent use of the CarD functional modules in resisting oxidative stress and pigmentation. These studies provide new information regarding the functional domains involved in transcriptional regulation by CarD while also improving understanding of the physiology of M. tuberculosis.

Exploring interference from analgesia in patients with cancer pain: a longitudinal qualitative study.

AIMS AND OBJECTIVES: To increase understanding of the impact of analgesic side effects in patients with cancer pain. BACKGROUND: Studies in the area of cancer pain often refer to the need to find a satisfactory balance between analgesics and side effects as the key to cancer pain management. We explore how patients achieve this balance, its components and how it affects pain treatment adherence. DESIGN: An exploratory longitudinal study using qualitative research methodology. METHODS: Twenty-five semi-structured face-to-face interviews with patients with advanced cancer and their caregivers. Longitudinal interviews were conducted with patients (n = 11) at six-week intervals over three months. Eleven first interviews, eight second interviews and six third interviews were completed with attrition due to death or ill health. Ten of the 25 interviews included caregivers. RESULTS: How cancer pain analgesics interfere with patients' life determines their adherence to the prescribed treatment. Compromises were made to manage three elements: pain, cognitive adverse effects of analgesics and physical activity. Negotiations and choices within this triad fluctuated and were determined by multiple psychosocial circumstances affecting patients and their caregivers varying from simple to complex. Patients with cancer and their caregivers actively managed the interference of analgesic drugs in their cognitive abilities and displayed a variety of nonadherence behaviours. CONCLUSION: Further understanding of the role of analgesic side effects in the success of cancer pain management in patients is needed. This would enable clinicians to frame an optimal pain management plan. RELEVANCE TO CLINICAL PRACTICE: Clinicians should advise their patients about side effects of analgesic drugs, specifically the impact that cognitive alterations might have on their lives and subsequent adherence behaviour. Helping patients to achieve a balance between pain, adverse effects and physical function should have a key place in pain management strategies with advanced cancer.

Evaluating deceased organ donation: a programme theory approach.

PURPOSE: Organ donation and transplantation services represent a microcosm of modern healthcare organisations. They are complex adaptive systems. They face perpetual problems of matching supply and demand. They operate under fierce time and resource constraints. And yet they have received relatively little attention from a systems perspective. The purpose of this paper is to consider some of the fundamental issues in evaluating, improving and policy reform in such complex systems. DESIGN/METHODOLOGY/APPROACH: The paper advocates an approach based on programme theory evaluation. FINDINGS: The paper explains how the death to donation to transplantation process depends on the accumulation of series of embedded, institutional sub-processes. Evaluators need to be concerned with this whole system rather than with its discrete parts or sectors. Policy makers may expect disappointment if they seek to improve donation rates by applying nudges or administrative reforms at a single point in the implementation chain. ORIGINALITY/VALUE: These services represent concentrated, perfect storms of complexity and the paper offers guidance to practitioners with bio-medical backgrounds on how such services might be evaluated and improved. For the methodological audience the paper caters for the burgeoning interest in programme theory evaluation while illustrating the design phase of this research strategy.

Understanding the barriers to integrating maternal and mental health at primary health care in Vietnam.

The prevalence of common perinatal mental disorders in Vietnam ranges from 16.9% to 39.9%, and substantial treatment gaps have been identified at all levels. This paper explores constraints to the integration of maternal and mental health services at the primary healthcare level and the implications for the health system's responsiveness to the needs and expectations of pregnant women with mental health conditions in Vietnam. As part of the RESPONSE project, a three-phase realist evaluation study, we present Phase 1 findings, which employed systematic and scoping literature reviews and qualitative data collection (focus groups and interviews) with key health system actors in Bac Giang province, Vietnam, to understand the barriers to maternal mental healthcare provision, utilization and integration strategies. A four-level framing of the barriers to integrating perinatal mental health services in Vietnam was used in reporting findings, which comprised individual, sociocultural, organizational and structural levels. At the sociocultural and structural levels, these barriers included cultural beliefs about the holistic notion of physical and mental health, stigma towards mental health, biomedical approach to healthcare services, absence of comprehensive mental health policy and a lack of mental health workforce. At the organizational level, there was an absence of clinical guidelines on the integration of mental health in routine antenatal visits, a shortage of staff and poor health facilities. Finally, at the provider level, a lack of knowledge and training on mental health was identified. The integration of mental health into routine antenatal visits at the primary care level has the potential help to reduce stigma towards mental health and improve health system responsiveness by providing services closer to the local level, offering prompt attention, better choice of services and better communication while ensuring privacy and confidentiality of services. This can improve the demand for mental health services and help reduce the delay of care-seeking.