Search

Systematic reviews require detailed planning of complex processes which can present logistical challenges. Understanding these logistical challenges can help with planning and execution of tasks OBJECTIVES: To describe the perspectives of expert searchers on the main logistical challenges when carrying out supplementary searches for systematic reviews, in particular, forward citation searching and web searching.Qualitative interviews were undertaken with 15 experts on searching for studies for systematic reviews (e.g. information specialists) working in health and social care research settings. Interviews were undertaken by video-call between September 2020 and June 2021. Data analysis used thematic network analysis.We identified three logistical challenges of using forward citation searching and web searching which were organised under the global theme of 'tension': time, team and technology. Several subthemes were identified which supported the organising themes, including allocating time, justifying time and keeping to time; reviewer expectations and contact with review teams; and access to resources and reference management.Forward citation searching and web searching are logistically challenging search methods for a systematic review. An understanding of these challenges should encourage expert searchers and review teams to maintain open channels of communication, which should also facilitate improved working relationships.

Aim:\ud This systematic review identifies, appraises and synthesizes the evidence on the provision of fundamental nursing care to hospitalized patients with a highly infectious virus and the effectiveness of adaptations to overcome barriers to care.\ud \ud Design:\ud Systematic review.\ud \ud Data Sources:\ud In July 2020, we searched Medline, PsycINFO (OvidSP), CINAHL (EBSCOhost), BNI (ProQuest), WHO COVID-19 Database (https://search.bvsalud.org/) MedRxiv (https://www.medrxiv.org/), bioRxiv (https://www.biorxiv.org/) and also Google Scholar, TRIP database and NICE Evidence, forwards citation searching and reference checking of included papers, from 2016 onwards.\ud \ud Review Methods:\ud We included quantitative and qualitative research reporting (i) the views, perceptions and experiences of patients who have received fundamental nursing care whilst in hospital with COVID-19, MERS, SARS, H1N1 or EVD or (ii) the views, perceptions and experiences of professional nurses and non-professionally registered care workers who have provided that care. We included review articles, commentaries, protocols and guidance documents. One reviewer performed data extraction and quality appraisal and was checked by another person.\ud \ud Results:\ud Of 3086 references, we included 64 articles; 19 empirical research and 45 review articles, commentaries, protocols and guidance documents spanning five pandemics. Four main themes (and 11 sub-themes) were identified. Barriers to delivering fundamental care were wearing personal protective equipment, adequate staffing, infection control procedures and emotional challenges of care. These barriers were addressed by multiple adaptations to communication, organization of care, staff support and leadership.\ud \ud Conclusion:\ud To prepare for continuation of the COVID-19 pandemic and future pandemics, evaluative studies of adaptations to fundamental healthcare delivery must be prioritized to enable evidence-based care to be provided in future.\ud \ud Impact:\ud Our review identifies the barriers nurses experience in providing fundamental care during a pandemic, highlights potential adaptations that address barriers and ensure positive healthcare experiences and draws attention to the need for evaluative research on fundamental care practices during pandemics.

© 2019 The Authors. Research Synthesis Methods published by John Wiley & Sons Ltd The incorporation of evidence derived from multiple research designs into one single synthesis can enhance the utility of systematic reviews making them more worthwhile, useful, and insightful. Methodological guidance for mixed-methods synthesis continues to emerge and evolve but broadly involves a sequential, parallel, or convergent approach according to the degree of independence between individual syntheses before they are combined. We present two case studies in which we used novel and innovative methods to draw together the findings from individual but related quantitative and qualitative syntheses to aid interpretation of the overall evidence base. Our approach moved beyond making a choice between parallel, sequential, or convergent methods to interweave the findings of individual reviews and offers three key innovations to mixed-methods synthesis methods: The use of intersubjective questions to understand the findings of the individual reviews through different lenses, Immersion of key reviewers in the entirety of the evidence base, and Commencing the process during the final stages of the synthesis of individual reviews, at a point where reviewers are developing an understanding of initial findings. Underlying our approach is the process of exploration and identification of links between and across review findings, an approach that is fundamental to all evidence syntheses but usually occurs at the level of the study. Adapting existing methods for exploring and identifying patterns and links between and across studies to interweave the findings between and across reviews may prove valuable.

Young people's wellbeing is often lowest where they assume a relatively low position within their school's socioeconomic hierarchy, for example, among poorer children attending more affluent schools. Transition to secondary school is a period during which young people typically enter an environment which is more socioeconomically diverse than their primary school. Young people joining a school with a higher socioeconomic status intake relative to their primary school may assume a relatively lowered position within their school's socioeconomic hierarchy, experiencing a detriment to their wellbeing as a consequence. This article draws on data from 45,055 pupils in Years 7 and 8, from 193 secondary schools in Wales, who completed the 2017 Student Health Research Network (SHRN) Student Health and Wellbeing (SHW) survey. Pupils reported which primary school they previously attended, and survey data on wellbeing were linked to publicly available data on the free school meal entitlement of schools attended. In cross-classified linear mixed-effects models, with primary and secondary school as levels, mental wellbeing varied significantly according to both primary and secondary school attended. A higher school-level deprivation was associated with worse mental wellbeing in both cases. Mental wellbeing was significantly predicted by the relative affluence of a child's primary and secondary school, with movement to a secondary school of higher overall socioeconomic status associated with lowered wellbeing. These findings highlight transition to secondary school as a key point in which socioeconomic inequality in wellbeing may widen, and thus as an important focal point for intervention to reduce health inequalities.

© 2020 World Health Organization; licensed by IAS. Introduction: As adolescents transition from childhood to adulthood, they experience major physical, social and psychological changes, and are at heightened risk for developing mental health conditions and engaging in health-related risk behaviours. For adolescents living with HIV (ALHIV), these risks may be even more pronounced. Research shows that this population may face additional mental health challenges related to the biological impact of the disease and its treatment, the psychosocial burdens of living with HIV and HIV-related social and environmental stressors. Discussion: Psychosocial interventions delivered to adolescents can promote positive mental health, prevent mental health problems and strengthen young people’s capacity to navigate challenges and protect themselves from risk. It is likely that these interventions can also benefit at-risk populations, such as ALHIV, yet there is little research on this. There is an urgent need for more research evaluating the effects of interventions designed to improve the mental health of ALHIV. We highlight four priorities moving forward. These include: generating more evidence about preventive mental health interventions for ALHIV; including mental health outcomes in research on psychosocial interventions for ALHIV; conducting intervention research that is sensitive to differences among ALHIV populations and involving adolescents in intervention design and testing. Conclusions: More robust research on promotive and preventive mental health interventions is needed for ALHIV. Programmes should be informed by adolescent priorities and preferences and responsive to the specific needs of these groups.

Qualitative comparative analysis (QCA) was originally developed as a tool for cross-national comparisons in macrosociology, but its use in evaluation and evidence synthesis of complex interventions is rapidly developing. QCA is theory-driven and relies on Boolean logic to identify pathways to an outcome (eg, is the intervention effective or not?). We use the example of two linked systematic reviews on weight management programs (WMPs) for adults-one focusing on user views (a "views synthesis") and one focusing on the effectiveness of WMPs incorporating dietary and physical activity-to demonstrate how a synthesis of user views can supply a working theory to structure a QCA. We discuss how a views synthesis is especially apt to supply this working theory because user views can (a) represent a "middle-range theory" of the intervention; (b) bring a participatory, democratic perspective; and (c) provide an idiographic understanding of how the intervention works that external taxonomies may not be able to furnish. We then discuss the practical role that the views synthesis played in our QCA examining pathways to effectiveness: (a) by suggesting specific intervention features and sharpening the focus on the most salient features to be examined, (b) by supporting interpretation of findings, and (c) by bounding data analysis to prevent data dredging.

This guide accompanies the following article: Nye, E., Melendez‐Torres, G.J. & Gardner, F. Mixed methods systematic review on effectiveness and experiences of the Incredible Years Teacher Classroom Management programme. Review of Education, https://doi.org/10.1002/rev3.3145

Background: Prevention of substance (alcohol, tobacco, illegal/legal drug) use in adolescents is a public health priority. As the scope for school ‐ based health education is constrained in school timetables, interventions integrating academic and health education have gained traction in the UK and elsewhere, though evidence for their effectiveness remains unclear. We sought to syn- thesize the effectiveness of interventions integrating academic and health education for the pre- vention of substance use. Methods: We searched 19 databases between November and December 2015, among other methods. We included randomized trials of interventions integrating academic and health educa- tion targeting school students aged 4 – 18 and reporting substance use outcomes. We excluded interventions for specific health ‐ related subpopulations (e.g., children with behavioural difficul- ties). Data were extracted independently in duplicate. Outcomes were synthesized by school key stage (KS) using multilevel meta ‐ analyses, for substance use, overall and by type. Results: We identified 7 trials reporting substance use. Interventions reduced substance use generally in years 7 – 9 (KS3) based on 5 evaluations ( d = − 0.09, 95% CI [ − 0.17, − 0.01], I 2 = 35%), as well as in years 10 – 11 (KS4) based on 3 evaluations ( − 0.06, [ − 0.09, − 0.02]; I 2 = 0%). Interventions were broadly effective for reducing specific alcohol, tobacco, and drug use in both KS groups. Conclusions: Evidence quality was highly variable. Findings for years 3 – 6 and 12 – 13 could not be meta ‐ analysed, and we could not assess publication bias. Interventions appear to have a small but significant effect reducing substance use. Specific methods of integrating academic and health education remain poorly understood.

In Brazil, automated teller machine (ATM) has become a major target of theft incursions toward explosion. Efficient analysis of explosives residues on suspect banknotes is a serious issue in forensic labs, and guide to the crime solution. Easy ambient sonic-spray ionization mass spectrometry (EASI-MS) is shown to be a simple and selective screening tool to identify peroxide explosives on real banknotes collected from ATM explosion. Analyses were carried out directly on the banknotes surfaces without any sample preparation, identifying triacetone triperoxide (TATP) and diacetone diperoxide (DADP). Homemade EASI source was coupled to ultrahigh-resolution and ultrahigh accuracy FT-ICR MS and revealed the ion of m/z 245 correspondent to sodiated TATP [C9H18O6Na]+ and the ion of m/z 171 related to sodiated DADP [C6H12O4Na]+, ions that is the sodiated DADP and the ions of m/z 173 and 189 related to [C6H14O4Na]+ and [C6H14O4K]+, respectively, which are associated to chemical markers of TATP domestic route synthesis. EASI source coupled to a single quadrupole mass spectrometer provides an intelligent and simple way to identify the explosives TATP, DADP and its domestic synthesis markers.

Using Toulmin's argumentation theory, we analysed the texts of systematic reviews in the area of workplace health promotion to explore differences in the modes of reasoning embedded in reports of narrative synthesis as compared with reports of meta-analysis. We used framework synthesis, grounded theory and cross-case analysis methods to analyse 85 systematic reviews addressing intervention effectiveness in workplace health promotion. Two core categories, or 'modes of reasoning', emerged to frame the contrast between narrative synthesis and meta-analysis: practical-configurational reasoning in narrative synthesis ('what is going on here? What picture emerges?') and inferential-predictive reasoning in meta-analysis ('does it work, and how well? Will it work again?'). Modes of reasoning examined quality and consistency of the included evidence differently. Meta-analyses clearly distinguished between warrant and claim, whereas narrative syntheses often presented joint warrant-claims. Narrative syntheses and meta-analyses represent different modes of reasoning. Systematic reviewers are likely to be addressing research questions in different ways with each method. It is important to consider narrative synthesis in its own right as a method and to develop specific quality criteria and understandings of how it is carried out, not merely as a complement to, or second-best option for, meta-analysis. © 2016 The Authors. Research Synthesis Methods published by John Wiley & Sons Ltd.

Coumarins are bioactive substances of the benzo-α-pyrone family, which have shown antioxidant, antiviral, anti-inflammatory and antitumor activities, among others. 7-Hydroxycoumarin and 6,7-dihydroxycoumarin (esculetin) are two coumarin derivatives that have been reported to exhibit antitumor activity, but the action mechanism underlying this activity remains unknown. In this work, to elucidate this mechanism, a theoretical study of the local and global electronic reactivity properties of a series of hydroxylated and dihydroxylated coumarin derivatives with possible antitumor action is performed using Density Functional Theory in aqueous solution. The substitution by one or two hydroxyl groups in the benzene ring of coumarin produces better charge-donor than charge-acceptor compounds. All the studied compounds are generally stable in water and exhibit permanent polarization in the solvent. With one hydroxyl substitution, 7-hydroxycoumarin is the most polar and polarizable derivative, whereas 5,7-dihydroxycoumarin is the most polar and polarizable compound with two hydroxyl substitutions. 5,7-Dihydroxycoumarin is suggested to possess antitumor activity. © 2016 Wiley Periodicals, Inc.

Introduction Reciprocal translation, the understanding of one study's findings in terms of another's, is the foundation of most qualitative metasynthetic methods. In light of the proliferation of metasynthesis methods, the current review sought to create a taxonomy of operations of reciprocal translation using recently published qualitative metasyntheses. Methods On 19 August 2013, MEDLINE, Embase and PsycINFO were searched. Included articles were full reports of metasyntheses of qualitative studies published in 2012 in English-language peer-reviewed journals. Two reviewers, working independently, screened records, assessed full texts for inclusion and extracted data on methods from each included metasynthesis. Systematic review methods used were summarised, and metasynthetic methods were inductively analysed to develop the taxonomy. Results Of 61 included metasyntheses, 21 (34%) reported fully replicable search strategies and 51 (84%) critically appraised included studies. Based on methods in these metasyntheses, we developed a taxonomy of reciprocal translation with four overlapping categories: visual representation; key paper integration; data reduction and thematic extraction; and line-by-line coding. Discussion This systematic review presents an update on methods and reporting currently used in qualitative metasynthesis. It also goes beyond the proliferation of approaches to offer a parsimonious approach to understanding how reciprocal translations are accomplished across metasynthetis methods. Copyright © 2015 John Wiley & Sons, Ltd.

Nitric oxide is implicated in the pathogenesis of various neuropathologies characterized by oxidative stress. Although nitric oxide has been reported to be involved in the exacerbation of oxidative stress observed in several neuropathologies, existent data fail to provide a holistic description of how nitrergic pathobiology elicits neuronal injury. Here we provide a comprehensive description of mechanisms contributing to nitric oxide induced neuronal injury by global transcriptomic profiling. Microarray analyses were undertaken on RNA from murine primary cortical neurons treated with the nitric oxide generator DETA-NONOate (NOC-18, 0.5 mM) for 8–24 hrs. Biological pathway analysis focused upon 3672 gene probes which demonstrated at least a ±1.5-fold expression in a minimum of one out of three time-points and passed statistical analysis (one-way anova, P < 0.05). Numerous enriched processes potentially determining nitric oxide mediated neuronal injury were identified from the transcriptomic profile: cell death, developmental growth and survival, cell cycle, calcium ion homeostasis, endoplasmic reticulum stress, oxidative stress, mitochondrial homeostasis, ubiquitin-mediated proteolysis, and GSH and nitric oxide metabolism. Our detailed time-course study of nitric oxide induced neuronal injury allowed us to provide the first time a holistic description of the temporal sequence of cellular events contributing to nitrergic injury. These data form a foundation for the development of screening platforms and define targets for intervention in nitric oxide neuropathologies where nitric oxide mediated injury is causative.

In this work, we present a complete structural and vibrational analysis of the OH torsional motion in difluorohydroxyborane (BF2OH) at the HF/aug-cc-pVTZ, MP2(full)/aug-cc-pVTZ, and CCSD/aug-cc-pVTZ theory levels. After full relaxation of the geometry, the equilibrium structure is found in a planar conformation of Cs symmetry. The difference in the two BF distances suggests the existence of a nonbonded interaction between the fluorine and oxygen atoms. The structural and energetic variation of BF2OH as a function of the OH torsional angle is considered. The torsional barrier, at the CCSD/aug-cc-pVTZ level, and including the effect of the zero-point energy of the remaining vibrations, is found 2,728 cm−1. In addition, an anharmonic Hamiltonian for the OH torsional mode is presented and variationally solved. To simplify the treatment and to classify the energy levels, BF2OH is classified under a G4 nonrigid group accounting for the inversion symmetry of the molecule and the interchange of the fluorine atoms. The computed torsional energy levels exhibit a very small inversion splitting. The torsional spectrum is simulated considering the dipole moment components along the principal axes of inertia as an explicit function of the torsional coordinate. We observe three dominant bands in the spectrum formed by doublets corresponding to ν9 = 0 1, 2 transitions. The fundamental is an a-type, Franck–Condon, transition. This is the strongest and appears at 466.80 cm−1 with relative intensity 0.4312. The ν9 = 0 2 bands correspond to doublets of b- and c-type, i.e., Herzberg–Teller transitions. These are two overlapping bands found at 890.92 and 890.94 cm−1 with intensity 0.2207 for the b-type band and 0.2193 for the c-type band. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011

Ab initio methods at the levels HF/cc-pVDZ, HF/6-31G(d,p), MP2/cc-pVDZ, and MP2/6-31G(d,p), as well as methods based on density functional theory (DFT) employing the hybrid functional B3LYP with the basis sets cc-pVDZ and 6-31G(d,p), have been applied to study the conformers of 2,6-distyrylpyridine. Bond distances, bond angles, and dihedral angles have been calculated at the B3LYP level. The calculated values were in good agreement with those measured by X-ray diffraction analysis of 2,6-distyrylpyridine. The values calculated using the Hartree-Fock method and second-order perturbation theory (MP2) were inconsistent. The optimized lowest-energy geometries were calculated from the reported X-ray structural data by the B3LYP/cc-pVDZ method. Three conformations, A, B, and C, were proposed for 2,6-distyrylpyridine. Calculations at the three levels of theory indicated that conformation A was the most stable structure, with conformations C and B being higher in energy by 1.10 and 2.57 kcal/mol, respectively, using the same method and basis function. The same trend in the relative energies of the three possible conformations was observed at the two levels of theory and with the different basis sets employed. The reported X-ray data were utilized to optimize total molecular energy of conformation A at the different calculation levels. The bond lengths, bond angles, and dihedral angles were then obtained from the optimized geometries by ab initio methods and by applying DFT using the two basis functions cc-pVDZ and 6-31G(d,p). The values were analyzed and compared. The calculated total energies, the relative energies of the molecular orbitals, the gap between them, and the dipole moment for each conformational structure proposed for 2,6-distyrylpyridine are also reported. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010

The anti-inflammatory activity of the phytoalexin resveratrol (RSV) was evaluated in C5 anaphylatoxin (C5a)-stimulated primary neutrophils and in a mouse model of acute peritonitis. Pretreatment of human and mouse neutrophils with RSV significantly blocked oxidative burst, leukocyte migration, degranulation, and inflammatory cytokine production. The anti-inflammatory activity of RSV was a function of inhibition of sphingosine kinase (SphK) activity (IC(50) approximately 20 microM) within 5 min of exposure, its membrane localization, and SphK1-mediated Ca(2+) release. As an experimental control, the SphK1 pharmacological inhibitor N,N-dimethyl sphingosine (DMS) was used to compare the inhibitory effect of RSV. We also provide evidence that the SphK inhibitory effect of RSV was mediated via its ability to block phospholipase D (PLD) activity and membrane recruitment. Furthermore, RSV blocked ERK1/2 phosphorylation, which functioned independently of SphK1 in this study. To provide in vivo relevance to these data, C5a-induced model of acute peritonitis was established, and the effects of prior injection of RSV were investigated. Indeed, prior injection of RSV virtually completely attenuated the effects of C5a on vascular permeability, neutrophil migration, release of interleukin 1beta, tumor necrosis factor alpha, interleukin 6, and the chemokine MIP-1alpha. Taken together, these data demonstrate strong anti-inflammatory activity of RSV in vitro and in vivo and highlight SphK1 as a potential target of this remarkable phytoalexin. These data could have tremendous implications for the clinical use of RSV in inflammatory pathologies.

Mast cell activation is a central event in allergic diseases, and investigating the signalling pathways triggered during mast cell activation may lead to the discovery of novel therapeutic targets. Mast cells can be activated by a multitude of stimuli including antibodies/antigen, cytokines/chemokines and neuropeptides, resulting in a variety of responses including the immediate release of potent inflammatory mediators. Moreover, recent data suggest that mast cell-mediated responses are also influenced by the differential sphingolipids/sphingosine to sphingosine-1-phosphate ratio. The importance of sphingolipids as potent biological mediators of both intracellular and extracellular responses is being increasingly recognized and accepted; it is now appreciated that activation of mast cells, via the high-affinity IgE-receptor (FcepsilonRI) leads to the activation of sphingosine kinases (SphK), resulting in increased formation of sphingosine-1-phosphate. Furthermore, FcepsilonRI activates SphK-dependent calcium mobilization in mast cells, leading to degranulation, cytokine, and eicosanoid production, and chemotaxis. In the past two years a critical role for SphK in allergic responses in vivo has emerged. In this review, I focus on the current understanding of the role of sphingosine kinases during mast cell signalling in vitro and their role during hypersensitivity responses in vivo, and discuss the potential of these enzymes as novel therapeutic targets to treat allergic diseases.

Telomeres and telomerase appear to participate in the repair of broken DNA ends produced by oxidative damage. Arsenite is an environmental contaminant and a potent human carcinogen, which induces oxidative stress on cells via the generation of reactive oxygen species affecting cell viability and chromosome stability. It promotes telomere attrition and reduces cell survival by apoptosis. In this study, we used mouse embryonic fibroblasts (MEFs) from mice lacking telomerase RNA component (mTERC(-/-) mice) with long (early passage or EP) and short (late passage or LP) telomeres to investigate the extent of oxidative damage by comparing the differences in DNA damage, chromosome instability, and cell survival at 24 and 48 h of exposure to sodium arsenite (As3+; NaAsO2). There was significantly high level of DNA damage in mTERC(-/-) cells with short telomeres as determined by alkaline comet assay. Consistent with elevated DNA damage, increased micronuclei (MN) induction reflecting gross genomic instability was also observed. Fluorescence in situ hybridization (FISH) analysis revealed that increasing doses of arsenite augmented the chromosome aberrations, which contributes to genomic instability leading to possibly apoptotic cell death and cell cycle arrest. Microarray analysis has revealed that As3+ treatment altered the expression of 456 genes of which 20% of them have known functions in cell cycle and DNA damage signaling and response, cell growth, and/or maintenance. Results from our studies imply that short dysfunctional telomeres impair the repair of oxidative damage caused by arsenite. The results will have implications in risk estimation as well as cancer chemotherapy.

1. Microarrays, a recent development, provide a revolutionary platform to analyse thousands of genes at once. They have enormous potential in the study of biological processes in health and disease and, perhaps, microarrays have become crucial tools in diagnostic applications and drug discovery. 2. Microarray based studies have provided the essential impetus for biomedical experiments, such as identification of disease-causing genes in malignancies and regulatory genes in the cell cycle mechanism. Microarrays can identify genes for new and unique potential drug targets, predict drug responsiveness for individual patients and, finally, initiate gene therapy and prevention strategies. 3. The present article reviews the principles and technological concerns, as well as the steps involved in obtaining and analysing of data. Furthermore, applications of microarray based experiments in drug target identifications and validation strategies are discussed. 4. To exemplify how this tool can be useful, in the present review we provide an overview of some of the past and potential future aspects of microarray technology and present a broad overview of this rapidly growing field.

1. RNA interference (RNAi) is a robust method of post-transcriptional silencing of genes using double-stranded RNA (dsRNA) with sequence homology driven specificity. The dsRNA can be between 21 and 23 nucleotides long: this is converted to small interfering RNA (siRNA), which then mediates gene silencing by degradation/blocking of translation of the target mRNA. 2. RNA interference provides a simple, fast and cost-effective alternative to existing gene targeting approaches both in vitro and in vivo. The discovery of siRNAs that cause RNAi in mammalian cells opened the door to the therapeutic use of siRNAs. Highly intense research efforts are now aimed at developing siRNAs for therapeutic purposes. 3. Recent advances in the design and delivery of targeting molecules now allow efficient and highly specific gene silencing in mammalian systems. Synthetic siRNA libraries targeting thousands of mammalian genes are publicly available for high-throughput genetic screens for target discovery and validation. Recent studies have demonstrated the clinical potential of aptly designed siRNAs in various types of viral infections, cancer and renal and neurodegenerative disorders. 4. The present review provides insight into the novel therapeutic strategies of siRNA technology, which is the latest development in nucleic acid-based tools for knocking down gene expression, and its potential for silencing genes associated with various human diseases.

Although inhibition of the ubiquitin proteasome system has been postulated to play a key role in the pathogenesis of neurodegenerative diseases, studies have also shown that proteasome inhibition can induce increased expression of neuroprotective heat-shock proteins (HSPs). The global gene expression of primary neurons in response to treatment with the proteasome inhibitor lactacystin was studied to identify the widest range of possible pathways affected. Our results showed changes in mRNA abundance, both at different time points after lactacystin treatment and at different lactacystin concentrations. Genes that were differentially up-regulated at the early time point but not when most cells were undergoing apoptosis might be involved in an attempt to reverse proteasome inhibitor-mediated apoptosis and include HSP70, HSP22 and cell cycle inhibitors. The up-regulation of HSP70 and HSP22 appeared specific towards proteasome inhibitor-mediated cell death. Overexpression of HSP22 was found to protect against proteasome inhibitor-mediated loss of viability by up to 25%. Genes involved in oxidative stress and the inflammatory response were also up-regulated. These data suggest an initial neuroprotective pathway involving HSPs, antioxidants and cell cycle inhibitors, followed by a pro-apoptotic response possibly mediated by inflammation, oxidative stress and aberrant activation of cell cycle proteins.

This work presents an analysis of the equivalence of MP2 and DFT (B3LYP functional) conformational populations. As a test case, we select three cholinergic agents (trans-nicotine, acetylcholine, and the nicotinic analgesic ABT-594), where the minima on the conformational energy hypersurfaces expand a large range of energies (∼0–30 kJ mol−1). From energetic and structural data obtained in vacuo at the MP2 and B3LYP/cc-pVDZ levels, we build conformational partition functions, including the effect of the conformational kinetic energy and the rotovibrational coupling. Our results at a physiological temperature (37°C) show qualitative agreement in all cases. Quantitative agreement, however, is only found for trans-nicotine and ABT-594. In the first case, energy minima differ by

The 14α-demethylation of biosynthetic reactions is carried out exclusively by lanosta-8,24-dien-3β-ol (lanosterol). Theoretical calculations were done to determine the importance of this structure with the Hartree–Fock scheme. It was modeled on structures similar to lanosterol with variations on the endo between C8C9 (lanosta-7,24-dien-3β-ol and lanosta-6,24-dien-3β-ol) as compared with the exo between C24C25 (Lanosta-8-en-3β-ol) and the size of the side chain (27-norlanosta-8-en-3β-ol, 26,27-dinorlanosta-8-en-3β-ol, 25,26,27-trinorlanosta-8-en-3β-ol, 24,25,26,27-tetranorlanosta-8-en-3β-ol, 23,24,25,26,27-pentanorlanosta-8-en-3β-ol, 22,23,24,25,26,27-hexanorlanosta-8-en-3β-ol). Energetic, electronic, and orbital evidence was found. The theoretical data were analyzed and were found to be important for the 14α-demethylation, the presence of HOMO on the region C8C9 and C14C141, a negative charge on the outgoing methyl C141. This atomic charge varies with the size of the side chain, and with the modification of the endo and exo double bonds. The conformation of the structure of the steroid is also related to its reactivity. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006

C-reactive protein (CRP) is the prototypic acute-phase protein in man which performs innate immune functions. CRP-mediated phagocytosis may be indirect, through activation of complement and complement receptors, or direct, through receptors for the Fc portion of immunoglobulin G (IgG; FcgammaRs) or even a putative CRP-specific receptor. No strong evidence has been shown to indicate which receptors may be responsible for phagocytosis or signalling responses. Using BIAcore technology, we confirm that CRP binds directly to the extracellular portion of FcgammaRI with a threefold higher affinity than IgG (KD = 0.81 x 10-9 m). Binding is Ca2+ dependent and is inhibited by IgG1 but not by phosphorylcholine (PC). CRP opsonization (using CRP concentrations within the normal human serum range) of PC-conjugated sheep erythrocytes increased phagocytosis of these particles by COS-7 cells transfected with FcgammaRI-II chimaera or FcgammaRI/gamma-chain. Interferon-gamma-treated U937 cells, which signal through FcgammaRI to activate phospholipase D (PLD) in response to cross-linked IgG, were also activated by CRP without any requirement for further cross-linking. These studies indicate that CRP is capable of binding to and cross-linking FcgammaRI thereby resulting in PLD activation and increased phagocytosis. Uptake by FcgammaRI has been reported to promote various acquired immune responses suggesting that CRP could act in a similar way.

The human high affinity receptor for immunoglobulin G, FcgammaRI, in dibutyryl cyclic AMP (dbcAMP)-differentiated U937 cells, is coupled to the activation of phospholipase C (PLC) and the conventional protein kinase C (PKC) isoforms, alpha, beta, and gamma. Here we demonstrate that aggregation of FcgammaRI activates the tyrosine-kinase regulated form of phosphatidylinositol-3-kinase (PI-3-kinase) and that an increase of phosphatidylinositol trisphosphate (PIP3) is essential for the activation and translocation of PLCgamma1 in these cells. In addition, activation of the PKC isoforms was ablated by specific inhibitors of PI3-kinase or by overexpression of a dominant negative p85 subunit of PI3-kinase. The findings reported here demonstrate that PLCgamma1 and PKC activation by FcgammaRI are downstream of PI3-kinase, and that in contrast to cytokine primed cells, only the tyrosine-kinase activated isoform of PI3-kinase is coupled to FcgammaRI in dbcAMP-differentiated cells.

Aggregation of receptors for the constant region (Fc) of immunoglobulin G on myeloid cells results in endocytosis or phagocytosis and cellular activation. Previous work has shown, using the cell line U937, that the high-affinity immunoglobulin G receptor, FcgammaRI, activates alternate intracellular signalling pathways depending on the cell differentiation state, which results in a marked change in the nature of calcium transients within the cell. Here, we show that protein kinase C (PKC) is activated in both interferon-gamma (IFN-gamma) -primed and dibutyryl cyclic AMP (dbcAMP) -differentiated cells but that the nature of the particular isoenzymes recruited differs. Thus, in IFN-gamma-primed U937 cells, FcgammaRI aggregation results in an increase of PKC activity which is essentially calcium independent resulting from the translocation to the membrane of the novel PKCs, delta and epsilon, together with the atypical PKC zeta. However, in cells differentiated to a more macrophage phenotype, all PKC enzyme activity after receptor aggregation is calcium dependent. Consistent with this finding, the isoenzymes translocated to the nuclear-free membrane fraction are the conventional PKCs alpha, beta and gamma; results consistent with our previous finding that FcgammaRI couples to phospholipase C in such dbcAMP-differentiated cells. Thus, the nature of PKC isoenzyme activated following FcgammaRI aggregation is defined by differentiation. The calcium dependence of the PKC isoenzyme is consistent with the duration of calcium transients previously reported in the two differentiation states.