To develop SAR at both the cannabinoid CB1 and CB2 receptors for 3-(1-naphthoyl)indoles bearing moderately electron withdrawing substituents at C-4 of the naphthoyl moiety, 1-propyl and 1-pentyl-3-(4-fluoro, chloro, bromo and iodo-1-naphthoyl) derivatives were prepared. To study the steric and electronic effects of substituents at the 8-position of the naphthoyl group, the 3-(4-chloro, bromo and iodo-1-naphthoyl)indoles were also synthesized. The affinities of both groups of compounds for the CB1 and CB2 receptors were determined and several of them were evaluated in vivo in the mouse. The effects of these substituents on receptor affinities and in vivo activity are discussed and structure-activity relationships are presented. Although many of these compounds are selective for the CB2 receptor, only three JWH-423, 1-propyl-3-(4-iodo-1-naphthoyl)indole, JWH-422, 2-methyl-1-propyl-3-(4-iodo-1-naphthoyl)indole, the 2-methyl analog of JWH-423 and JWH-417, 1-pentyl-3-(8-iodo-1-naphthoyl)indole, possess the desirable combination of low CB1 affinity and good CB2 affinity.
doi:10.1016/j.bmc.2012.01.038
PMCID: PMC3298571
PMID: 22341572
cannabinoids; structure-activity relationships; cannabinoid receptors; aminoalkylindole
The recent crystal structure of two monoferric human serum transferrin (FeNhTF) molecules bound to the soluble portion of the homodimeric transferrin receptor (sTFR) has provided new details of this binding interaction which dictates iron delivery to cells. Specifically, substantial rearrangements in the homodimer interface of the sTFR occur as a result of the binding of the two FeNhTF molecules. Mutagenesis of selected residues in the sTFR highlighted in the structure was undertaken to evaluate the effect on function. Elimination of Ca2+ binding in the sTFR by mutating two of four coordinating residues ([E465A,E468A]) results in low production of an unstable and aggregated sTFR. Mutagenesis of two histidines ([H475A,H684A]) at the dimer interface had little effect on the kinetics of iron release at pH 5.6 from either lobe, reflecting the inaccessibility of this cluster to solvent. Creation of a H318A sTFR mutant allows assignment of a small pH dependent initial decrease in the fluorescent signal to His318. Removal of the four C-terminal residues of the sTFR, Asp757-Asn758-Glu759-Phe760, eliminates pH-stimulated iron release from the C-lobe of the Fe2hTF/sTFR Δ757–760 complex. The loss is accounted for by the inability of this sTFR mutant to bind and stabilize protonated hTF His349 (a pH-inducible switch) in the C-lobe of hTF. Collectively, these studies support a model in which a series of pH-induced events involving both TFR residue His318 and hTF residue His349 occurs in order to promote receptor-stimulated iron release from the C-lobe of hTF.
doi:10.1021/bi3001038
PMCID: PMC3302921
PMID: 22356162
Efficient delivery of iron is critically dependent on the binding of diferric human serum transferrin (hTF) to its specific receptor (TFR) on the surface of actively dividing cells. Internalization of the complex into an endosome precedes iron removal. The return of hTF to the blood to continue the iron delivery cycle relies on the maintenance of the interaction between apohTF and the TFR after exposure to endosomal pH (≤ 6.0). Identification of the specific residues accounting for the pH-sensitive nanomolar affinity with which hTF binds to TFR throughout the cycle is important to fully understand the iron delivery process. Alanine substitution of eleven charged hTF residues identified by available structures and modeling studies allowed evaluation of the role of each in (1) binding of hTF to the TFR and (2) in TFR-mediated iron release. Six hTF mutants (R50A, R352A, D356A, E357A, E367A and K511A) competed poorly with biotinylated diferric hTF for binding to TFR. In particular, we show that Asp356 in the C-lobe of hTF is essential to the formation of a stable hTF/TFR complex: mutation of Asp356 in the monoferric C-lobe hTF background prevented the formation of the stoichiometric 2:2 (hTF:TFR monomer) complex. Moreover, mutation of three residues (Asp356, Glu367 and Lys511), whether in the diferric or monoferric C-lobe hTF, significantly affected iron release when in complex with the TFR. Thus, mutagenesis of charged hTF residues has allowed identification of a number of residues that are critical to formation of and iron release from the hTF/TFR complex.
doi:10.1021/bi201661g
PMCID: PMC3267578
PMID: 22191507
Background
Current recommendations do not support the use of continuous electronic fetal monitoring (EFM) for low risk women during labour, yet EFM remains widespread in clinical practice. Consideration of the views, perspectives and experiences of individuals directly concerned with EFM application may be beneficial for identifying barriers to and facilitators for implementing evidence-based maternity care. The aim of this paper is to offer insight and understanding, through systematic review and thematic analysis, of research into professionals’ views on fetal heart rate monitoring during labour.
Methods
Any study whose aim was to explore professional views of fetal monitoring during labour was considered eligible for inclusion. The electronic databases of MEDLINE (1966–2010), CINAHL (1980–2010), EMBASE (1974–2010) and Maternity and Infant Care: MIDIRS (1971–2010) were searched in January 2010 and an updated search was performed in March 2012. Quality appraisal of each included study was performed. Data extraction tables were developed to collect data. Data synthesis was by thematic analysis.
Results
Eleven studies, including 1,194 participants, were identified and included in this review. Four themes emerged from the data: 1) reassurance, 2) technology, 3) communication/education and 4) midwife by proxy.
Conclusion
This systematic review and thematic analysis offers insight into some of the views of professionals on fetal monitoring during labour. It provides evidence for the continuing use of EFM when caring for low-risk women, contrary to current research evidence. Further research to ascertain how some of these views might be addressed to ensure the provision of evidence-based care for women and their babies is recommended.
doi:10.1186/1471-2393-12-166
PMCID: PMC3549751
PMID: 23270400
Fetal monitoring; Pregnancy; Labour; Views
Objectives
To quantify geographical concentration of falciparum malaria cases in the UK at a hospital level. To assess potential delay-to-treatment associated with hub-and-spoke distribution of artesunate in severe cases.
Design
Observational study using national and hospital data.
Setting and participants
3520 patients notified to the Malaria Reference Laboratory 2008–2010, 34 patients treated with intravenous artesunate from a tropical diseases centre 2002–2010.
Main outcome measures
Geographical location of falciparum cases notified in the UK. Diagnosis-to-treatment times for intravenous artesunate.
Results
Eight centres accounted for 43.9% of the UK's total cases; notifications from 107 centres accounted for 10.2% of cases; 51.5% of hospitals seeing malaria notified 5 or fewer cases in 3 years. Centres that saw <10 cases/year treat 26.3% of malaria cases; 6.1% of cases are treated in hospitals seeing <2 cases/year. Concentration of falciparum malaria was highest in Greater London (1925, 54.7%), South East (515, 14.6%), East of England (402, 11.4%) and North West (192, 5.4%). The North East and Northern Ireland each notified 5 or fewer cases per year. Median diagnosis-to-treatment time was 1 h (range 0.5–5) for patients receiving artesunate in the specialist centre; 7.5 h (range 4–26) for patients receiving it in referring hospitals via the hub-and-spoke system (p=0.02); 25 h (range 9–45) for patients receiving it on transfer to the regional centre from a referring hospital (p=0.002).
Conclusions
Most UK hospitals see few cases of falciparum malaria and geographical distances are significant. Over 25% of cases are seen in hospitals where malaria is rare, although 60% are seen in hospitals seeing over 50 cases over 3 years. A hub-and-spoke system minimises drug wastage and ensures availability in centres seeing most cases but is associated with treatment delays elsewhere. As with all observational studies, there are limitations, which are discussed.
doi:10.1136/bmjopen-2012-001854
PMCID: PMC3533059
PMID: 23148346
Infectious Diseases; Parasitology
Purpose
MegaCell DCS, an animal product-free culture medium formulated for storing corneas, is superior to the traditionally used MEM (Eagle’s) with Earles salts, Hepes, and supplemented with foetal calf serum (2 %), glutamine and an antibiotic cocktail (EB MEM). Because this medium does not prevent corneal swelling, and Dextran T500, which is traditionally used for reversing this process before transplant may have adverse effects on corneas, the purpose of the current investigation was to identify an alternative polymer that is compatible with MegaCell DCS.
Methods
Corneas maintained in MegaCell DCS or EB MEM were transferred to either EB MEM 5 % Dextran T500 or MegaCell DCS containing 5 % Dextran T500, 4 % polyethylene glycol (PEG) 10,000, PEG 35,000 (2 %, 3 %, 4 %) or Poloxamer 188 (4 %). Endothelial cell losses were determined and corneal hydration levels measured. Stromal cell cultures were generated and immunostained with anti α-SMA antibody. Janus Green was used to compare the viability of endothelial cells of corneas maintained in MegaCell DCS and EB MEM and respectively thinned with PEG 35,000 and Dextran T500.
Results
The rates of endothelial cell loss from corneas held in MegaCell DCS and thinned in MegaCell DCS containing 5 % Dextran T500, 4 % PEG 10,000 and 4 % Poloxamer 188 for 6 days were similar. When explants of these corneas were cultured myofibroblasts were generated. Although at concentrations of 4 % (w/v) both PEG 10,000 and Poloxamer 188 caused excessive dehydration, the hydration levels of corneas held in MegaCell DCS containing 3 % PEG 35,000 were similar to those of corneas held in EB MEM 5 % Dextran T500. Endothelial cell losses after 6 days were negligible, explants of the corneas generated uniform fibroblastic stromal cell cultures and the extents of Janus Green staining were similar. Over 20 days the inclusion of 5 % Dextran T500 in EB MEM but not 3 % PEG 35,000 in MegaCell DCS, increased the rate of endothelial cell loss.
Conclusion
PEG 35,000 at a concentration of 3 % w/v does not induce endothelial cell loss and is compatible with MegaCell DCS for thinning corneas prior to transplantation.
doi:10.1007/s00417-012-2126-1
PMCID: PMC3501186
PMID: 23011001
Cornea; Corneal organ culture medium; Corneal transplant; Corneal endothelium; Epithelial cells; Keratocytes
Essential to iron transport and delivery, human serum transferrin (hTF) is a bilobal glycoprotein capable of reversibly binding one ferric ion in each lobe (the N- and C-lobes). A complete description of iron release from hTF, as well as insight into the physiological significance of the bilobal structure, demands characterization of the isolated lobes. Although production of large amounts of isolated N-lobe and full-length hTF has been well documented, attempts to produce the C-lobe (by recombinant and/or proteolytic approaches) have met with more limited success. Our new strategy involves replacing the hepta-peptide, PEAPTDE (comprising the bridge between the lobes) with the sequence ENLYFQ/G in a His-tagged non-glycosylated monoferric hTF construct, designated FeChTF. The new bridge sequence of this construct, designated FeCTEV hTF, is readily cleaved by the tobacco etch virus (TEV) protease yielding non-glycosylated C-lobe. Following nickel column chromatography (to remove the N-lobe and the TEV protease which are both His tagged), the homogeneity of the C-lobe has been confirmed by mass spectroscopy. Differing reactivity with a monoclonal antibody specific to the C-lobe indicates that introduction of the TEV cleavage site into the bridge alters its conformation. The spectral and kinetic properties of the isolated C-lobe differ significantly from those of the isolated N-lobe.
doi:10.1016/j.pep.2010.01.008
PMCID: PMC2860049
PMID: 20064616
Tobacco etch virus protease; transferrin; stopped-flow fluorescence; intrinsic tryptophan fluorescence; absorption coefficient determination; cooperativity
Background
Hundreds of studies of maternity care interventions have been published, too many for most people involved in providing maternity care to identify and consider when making decisions. It became apparent that systematic reviews of individual studies were required to appraise, summarise and bring together existing studies in a single place. However, decision makers are increasingly faced by a plethora of such reviews and these are likely to be of variable quality and scope, with more than one review of important topics. Systematic reviews (or overviews) of reviews are a logical and appropriate next step, allowing the findings of separate reviews to be compared and contrasted, providing clinical decision makers with the evidence they need.
Methods
The methods used to identify and appraise published and unpublished reviews systematically, drawing on our experiences and good practice in the conduct and reporting of systematic reviews are described. The process of identifying and appraising all published reviews allows researchers to describe the quality of this evidence base, summarise and compare the review's conclusions and discuss the strength of these conclusions.
Results
Methodological challenges and possible solutions are described within the context of (i) sources, (ii) study selection, (iii) quality assessment (i.e. the extent of searching undertaken for the reviews, description of study selection and inclusion criteria, comparability of included studies, assessment of publication bias and assessment of heterogeneity), (iv) presentation of results, and (v) implications for practice and research.
Conclusion
Conducting a systematic review of reviews highlights the usefulness of bringing together a summary of reviews in one place, where there is more than one review on an important topic. The methods described here should help clinicians to review and appraise published reviews systematically, and aid evidence-based clinical decision-making.
doi:10.1186/1471-2288-11-15
PMCID: PMC3039637
PMID: 21291558
doi:10.1080/00304948.2010.514799
PMCID: PMC2957014
PMID: 20976119
doi:10.1186/1475-2875-9-S2-I10
PMCID: PMC2963201
Background
Sorsby's fundus dystrophy (SFD) is a degenerative retinopathy characterised by accumulation of mutant TIMP‐3 protein in Bruch's membrane.
Aim
To compare the stability of matrix bound SFD mutant TIMP‐3s with wild type TIMP‐3.
Methods
COS‐7 cells were transfected with plasmids containing wild type, Ser 181, Gly‐167, Ser‐156, and Tyr‐168 TIMP‐3 cDNA. The cells and their matrices were subsequently harvested and homogenised. After measuring the bound wild type and SFD mutant TIMP‐3 concentrations by ELISA, aliquots of the homogenates were heated to 100°C. The rates of denaturation of the TIMP proteins at this temperature were monitored by reverse zymography.
Results
Over a period of 24 h at 100°C the biological activity of both wild type and SFD mutant TIMP‐3 was lost. Over a period of 6 h at this temperature the biological activity of the SFD mutant TIMP‐3s was fully retained whereas that of the wild type TIMP‐3 was lost.
Conclusion
Matrix bound SFD mutant TIMP‐3s are thermodynamically more stable than wild type. This may explain why SFD starts earlier in life than age related macular degeneration.
doi:10.1136/bjo.2006.113225
PMCID: PMC1954801
PMID: 17383996
Bruch's membrane; TIMP‐3 gene transfer; Sorsby's fundus dystrophy; age related macular degeneration
Bosworth, Hayden B | Almirall, Daniel | Weiner, Bryan J | Maciejewski, Mathew | Kaufman, Miriam A | Powers, Benjamin J | Oddone, Eugene Z | Lee, Shoou-Yih D | Damush, Teresa M | Smith, Valerie | Olsen, Maren K | Anderson, Daren | Roumie, Christianne L | Rakley, Susan | Del Monte, Pamela S | Bowen, Michael E | Kravetz, Jeffrey D | Jackson, George L
Background
Despite the impact of hypertension and widely accepted target values for blood pressure (BP), interventions to improve BP control have had limited success.
Objectives
We describe the design of a 'translational' study that examines the implementation, impact, sustainability, and cost of an evidence-based nurse-delivered tailored behavioral self-management intervention to improve BP control as it moves from a research context to healthcare delivery. The study addresses four specific aims: assess the implementation of an evidence-based behavioral self-management intervention to improve BP levels; evaluate the clinical impact of the intervention as it is implemented; assess organizational factors associated with the sustainability of the intervention; and assess the cost of implementing and sustaining the intervention.
Methods
The project involves three geographically diverse VA intervention facilities and nine control sites. We first conduct an evaluation of barriers and facilitators for implementing the intervention at intervention sites. We examine the impact of the intervention by comparing 12-month pre/post changes in BP control between patients in intervention sites versus patients in the matched control sites. Next, we examine the sustainability of the intervention and organizational factors facilitating or hindering the sustained implementation. Finally, we examine the costs of intervention implementation. Key outcomes are acceptability and costs of the program, as well as changes in BP. Outcomes will be assessed using mixed methods (e.g., qualitative analyses--pattern matching; quantitative methods--linear mixed models).
Discussion
The study results will provide information about the challenges and costs to implement and sustain the intervention, and what clinical impact can be expected.
doi:10.1186/1748-5908-5-54
PMCID: PMC2914777
PMID: 20637095
Human serum transferrin (hTF), with two Fe3+ binding lobes transports iron into cells. Diferric hTF preferentially binds to a specific receptor (TFR) on the surface of cells and the complex undergoes clathrin dependent receptor-mediated endocytosis. The clathrin-coated vesicle fuses with an endosome where the pH is lowered, facilitating iron release from hTF. On a biologically relevant timescale (2-3 min), the factors critical to iron release include pH, anions, a chelator and the interaction of hTF with the TFR. Previous work, in which the increase in the intrinsic fluorescence signal was used to monitor iron release from the hTF/TFR complex, established that the TFR significantly enhances the rate of iron release from the C-lobe of hTF. In the current study, the role of the five C-lobe Trp residues in reporting the fluorescence change has been evaluated (± sTFR). Only four of the five recombinant Trp→ Phe mutants produced well. A single slow rate constant for iron release is found for the monoferric C-lobe (FeC hTF) and the four Trp mutants in the FeC hTF background. The three Trp residues equivalent to those in the N-lobe differed from the N-lobe and each other in their contributions to the fluorescent signal. Two rate constants are observed for the FeC hTF control and the four Trp mutants in complex with the TFR: kobsC1 reports conformational change(s) in the C-lobe initiated by the TFR and kobsC2 is ascribed to iron release. Excitation at 295 nm (Trp only) and at 280 nm (Trp and Tyr) reveals interesting and significant differences in the rate constants for the complex.
doi:10.1021/bi8022834
PMCID: PMC2664620
PMID: 19281173
Mason, Anne B. | Halbrooks, Peter J. | James, Nicholas G. | Byrne, Shaina L. | Grady, John K. | Chasteen, N. Dennis | Bobst, Cedric E. | Kaltashov, Igor A. | Smith, Valerie C. | MacGillivray, Ross T. A. | Everse, Stephen J.
The G65R mutation in the N-lobe of human transferrin was created to mimic a naturally occurring variant (G394R) found in the homologous C-lobe. Because Gly65 is hydrogen-bonded to the iron-binding ligand Asp63, it comprises part of the second shell hydrogen bond network surrounding the iron within the metal binding cleft of the protein. Substitution with an arginine residue at this position disrupts the network, resulting in much more facile removal of iron from the G65R mutant. As shown by UV-vis and EPR spectroscopy, and by kinetic assays measuring the release of iron, the G65R mutant can exist in three forms. Two of the forms (yellow and pink in color) are inter-convertible. The yellow form predominates in 1 M bicarbonate; the pink form is generated from the yellow form upon exchange into 1 M HEPES buffer, pH 7.4. The third form (also pink in color) is produced by the addition of Fe3+-(nitrilotriacetate)2 to apo-G65R. Hydrogen/deuterium exchange experiments are consistent with all forms of the G65R mutant assuming a more open conformation. Additionally, mass spectroscopic analysis reveals the presence of nitrilotriacetate in the third form. The inability to obtain crystals of the G65R mutant, led to development of a novel crystallization strategy in which the double mutation G65R/K206E stabilizes a single closed pink conformer and captures Arg65 in a single position. Collectively, these studies highlight the importance of the hydrogen bond network in the cleft, as well as the inherent flexibility of the N-lobe which although able to adapt to accommodate the large arginine substitution exists in multiple conformations.
doi:10.1021/bi802254x
PMCID: PMC2693239
PMID: 19219998
We previously demonstrated that decreasing the iron release rate of transferrin (Tf), by replacing the synergistic anion carbonate with oxalate, increases its in vitro drug carrier efficacy in HeLa cells. In the current work, the utility of this strategy has been further explored by generating two Tf mutants, K206E/R632A Tf and K206E/K534A Tf, exhibiting different degrees of iron release inhibition. The intracellular trafficking behavior of these Tf mutants has been assessed by measuring their association with HeLa cells. Compared to native Tf, the cellular association of K206E/R632A Tf and K206E/K534A Tf increased by 126 and 250%, respectively. Surface plasmon resonance studies clearly indicate that this increase in cellular association is due to a decrease in the iron release rate and not to differences in binding affinity of the mutants to the Tf receptor (TfR). Diphtheria toxin (DT) conjugates of K206E/R632A Tf and K206E/K534A Tf showed significantly increased cytotoxicity against HeLa cells with IC50 values of 1.00 pM and 0.93 pM, respectively, compared to a value of 1.73 pM for the native Tf conjugate. Besides further validating our strategy of inhibiting iron release, these Tf mutants provide proof-of-principle that site-directed mutagenesis offers an alternative method for improving the drug carrier efficacy of Tf.
doi:10.1016/j.jconrel.2008.10.006
PMCID: PMC2681226
PMID: 18992290
Transferrin; Diphtheria toxin; Site-directed mutagenesis; Intracellular trafficking; Targeted cancer therapy
All eukaryotic organisms, single-celled or multi-cellular, produce a diverse array of natural anti-infective agents that, in addition to conventional antimicrobial peptides, also include proteins and other molecules often not regarded as part of the innate defences. Examples range from histones, fatty acids, and other structural components of cells to pigments and regulatory proteins. These probably represent very ancient defence factors that have been re-used in new ways during evolution. This review discusses the nature, biological role in host protection and potential biotechnological uses of some of these compounds, focusing on those from fish, marine invertebrates and marine micro-algae.
doi:10.3390/md8041213
PMCID: PMC2866484
PMID: 20479976
amphipathicity; antimicrobial peptides; fatty acids; innate defence; pigments
The Friedel-Crafts acylation of N-p-toluenesulfonylpyrrole under Friedel-Crafts conditions has been reinvestigated. Evidence is presented in support of the hypothesis that when AlCl3 is used as the Lewis acid, acylation proceeds via reaction of an organoaluminum intermediate with the acyl halide. This leads to the production of the 3-acyl derivative as the major product. With weaker Lewis acids (EtAlCl2, Et2AlCl) or less than one equivalent of AlCl3 the relative amount of 2-acyl product is increased. A mechanistic rationalization is presented to explain these data.
doi:10.1016/j.tet.2007.12.043
PMCID: PMC2344136
PMID: 19247425
acylpyrrole; organoaluminum intermediates; Friedel-Crafts reaction; reaction mechanism
Background
Two thirds of all falciparum malaria cases reported in the United Kingdom (UK) are acquired in West Africa (WA). To ensure recommendations and guidelines for malaria prophylaxis in travellers to West Africa correlate to the risk of infection, a study was undertaken to examine recent trends and predict future patterns of imported malaria acquired by UK residents visiting West Africa and West African visitors to the UK between 1993 and 2006.
Methods and Results
Using passenger numbers and malaria surveillance reports, the data revealed a 2.3-fold increase in travel to West Africa with a five-fold increase in travelers visiting friends and relatives (VFR). Malaria incidence fell through the study period, the greatest decline noted in VFR with a fall from 196 cases/1,000 person-years to 52 cases/1,000 person-years, 9.8% per year p < 0.0001. The risk for travellers from the UK visiting for other reasons declined 2.7 fold, at an annual decrease of 7.0%, with the incidence in West African visitors to the UK falling by 2.3 fold, a rate of 7.9% annually.
Discussion
The reduction in incidence among all three groups of travellers may be explained by several factors; changing chemoprophylaxis usage and/or increased travel in urban areas where malaria risk has declined over the past decade, or widespread reduction in malaria transmission in West Africa.
Conclusion
With the reduction in malaria incidence seen in both visitors to and from West Africa, the most rational explanation for these findings is a fall in malaria transmission in West Africa, which may require a change in chemoprophylaxis policy for UK travelers over the next 5–10 years.
doi:10.1186/1475-2875-7-235
PMCID: PMC2613412
PMID: 19000299
Objective To examine temporal, geographic, and sociodemographic trends in case reporting and case fatality of malaria in the United Kingdom.
Setting National malaria reference laboratory surveillance data in the UK.
Design Observational study using prospectively gathered surveillance data and data on destinations from the international passenger survey.
Participants 39 300 cases of proved malaria in the UK between 1987 and 2006.
Main outcome measures Plasmodium species; sociodemographic details (including age, sex, and country of birth and residence); mortality; destination, duration, and purpose of international travel; and use of chemoprophylaxis.
Results Reported cases of imported malaria increased significantly over the 20 years of the study; an increasing proportion was attributable to Plasmodium falciparum (P falciparum/P vivax reporting ratio 1.3:1 in 1987-91 and 5.4:1 in 2002-6). P vivax reports declined from 3954 in 1987-91 to 1244 in 2002-6. Case fatality of reported P falciparum malaria did not change over this period (7.4 deaths per 1000 reported cases). Travellers visiting friends and relatives, usually in a country in Africa or Asia from which members of their family migrated, accounted for 13 215/20 488 (64.5%) of all malaria reported, and reports were geographically concentrated in areas where migrants from Africa and South Asia to the UK have settled. People travelling for this purpose were at significantly higher risk of malaria than other travellers and were less likely to report the use of any chemoprophylaxis (odds ratio of reported chemoprophylaxis use 0.23, 95% confidence interval 0.21 to 0.25).
Conclusions Despite the availability of highly effective preventive measures, the preventable burden from falciparum malaria has steadily increased in the UK while vivax malaria has decreased. Provision of targeted and appropriately delivered preventive messages and services for travellers from migrant families visiting friends and relatives should be a priority.
doi:10.1136/bmj.a120
PMCID: PMC2453297
PMID: 18599471
Objective To examine temporal, geographic, and sociodemographic trends in case reporting and case fatality of malaria in the United Kingdom.
Setting National malaria reference laboratory surveillance data in the UK.
Design Observational study using prospectively gathered surveillance data and data on destinations from the international passenger survey.
Participants 39 300 cases of proved malaria in the UK between 1987 and 2006.
Main outcome measures Plasmodium species; sociodemographic details (including age, sex, and country of birth and residence); mortality; destination, duration, and purpose of international travel; and use of chemoprophylaxis.
Results Reported cases of imported malaria increased significantly over the 20 years of the study; an increasing proportion was attributable to Plasmodium falciparum (P falciparum/P vivax reporting ratio 1.3:1 in 1987-91 and 5.4:1 in 2002-6). P vivax reports declined from 3954 in 1987-91 to 1244 in 2002-6. Case fatality of reported P falciparum malaria did not change over this period (7.4 deaths per 1000 reported cases). Travellers visiting friends and relatives, usually in a country in Africa or Asia from which members of their family migrated, accounted for 13 215/20 488 (64.5%) of all malaria reported, and reports were geographically concentrated in areas where migrants from Africa and South Asia to the UK have settled. People travelling for this purpose were at significantly higher risk of malaria than other travellers and were less likely to report the use of any chemoprophylaxis (odds ratio of reported chemoprophylaxis use 0.23, 95% confidence interval 0.21 to 0.25).
Conclusions Despite the availability of highly effective preventive measures, the preventable burden from falciparum malaria has steadily increased in the UK while vivax malaria has decreased. Provision of targeted and appropriately delivered preventive messages and services for travellers from migrant families visiting friends and relatives should be a priority.
doi:10.1136/bmj.a120
PMCID: PMC2453297
PMID: 18599471
Background: Sorsby's fundus dystrophy (SFD) and age related macular degeneration (ARMD) are retinal diseases associated with a high level of accumulation of mutant and wild type TIMP-3, respectively, in Bruch's membrane. The pathogenic role of TIMP-3 in these diseases is uncertain, but causative mutations have been identified in the TIMP-3 gene of patients with SFD. Recent reports that TIMP-3 causes apoptosis in certain cell types and not in others prompted the authors to investigate whether TIMP-3 causes apoptosis in cultured retinal pigment epithelium (RPE) cells.
Methods: RPE and MCF-7 cells (as a positive control) were initially infected with replication deficient adenovirus, to overexpress β-galactosidase (RAdLacZ) or TIMP-3 (RAdTIMP-3). TIMP-3 was detected by western blotting and ELISA. Cell viability was defined by cell counts. ISEL was used to investigate the mechanism of cell death.
Results: Cultured RPE cells produced small quantities of endogenous TIMP-3 and remained viable. However, overexpression of TIMP-3 caused a dose related death of RPE cells. The mechanism of cell death was apoptosis.
Conclusion: The previously unreported finding of TIMP-3 induced apoptosis of RPE cells may account for some of the early features seen in SFD and ARMD.
PMCID: PMC1770963
PMID: 11801512
gene transfer; retinal pigment epithelium; apoptosis; macular degeneration
The human gastric pathogen Helicobacter pylori attaches to antral epithelial cells in vivo. Cultured human antral epithelial cells, AGS and NCI-N87 cell lines, were grown in the absence or presence of H. pylori and compared with respect to gene transcript levels, protein expression, organization of the actin cytoskeleton, and the regulation of cell migration. The Clontech Neurobiology array detected differentially expressed transcripts, while Western blots were used to investigate related changes in protein levels. Infection with H. pylori consistently upregulated annexin II, S100 A7, Rho-GTP, and IQGAP-1, whereas SSTR-1 was downregulated upon H. pylori infection. In the adherens junction, E-cadherin and IQGAP-1 were translocated from the plasma membrane to intracellular vesicles. The primary and NCI-N87 cells were similar with respect to cell-cell and cell-matrix adhesion and cell migratory behavior; in contrast the AGS cells were significantly different from the primary gastric epithelial cell preparations, and thus caution must be used when using this cell line for studies of gastric disease. These studies demonstrate a correlation between H. pylori infection and alterations to epithelial cell adhesion molecules, including increased levels of Rho-GTP and cell migration. These data indicate that destabilizing epithelial cell adherence is one of the factors increasing the risk of H. pylori-infected individuals developing gastric cancer.
doi:10.1128/IAI.72.9.5181-5192.2004
PMCID: PMC517469
PMID: 15322013
Objectives To determine which travellers with malaria are at greatest risk of dying, highlighting factors which can be used to target health messages to travellers.
Design Observational study based on 20 years of UK national data.
Setting National register of malaria cases.
Participants 25 054 patients notified with Plasmodium falciparum malaria, of whom 184 died, between 1987 and 2006.
Main outcome measures Comparison between those with falciparum malaria who died and non-fatal cases, including age, reason for travel, country of birth, time of year diagnosed, malaria prophylaxis used.
Results Mortality increased steadily with age, with a case fatality of 25/548 (4.6%) in people aged >65 years, adjusted odds ratio 10.68 (95% confidence interval 6.4 to 17.8), P<0.001 compared with 18–35 year olds. There were no deaths in the ≤5 year age group. Case fatality was 3.0% (81/2740 cases) in tourists compared with 0.32% (26/8077) in travellers visiting friends and relatives (adjusted odds ratio 8.2 (5.1 to 13.3), P<0.001). Those born in African countries with endemic malaria had a case fatality of 0.4% (36/8937) compared with 2.4% (142/5849) in others (adjusted odds ratio 4.6 (3.1 to 9.9), P<0.001). Case fatality was particularly high from the Gambia. There was an inverse correlation in mortality between region of presentation and number of cases seen in the region (R2=0.72, P<0.001). Most delay in fatal cases was in seeking care.
Conclusions Most travellers acquiring malaria are of African heritage visiting friends and relatives. In contrast the risks of dying from malaria once acquired are highest in the elderly, tourists, and those presenting in areas in which malaria is seldom seen. Doctors often do not think of these as high risk groups for malaria; for this reason they are important groups to target in pre-travel advice.
doi:10.1136/bmj.e2116
PMCID: PMC3314185
PMID: 22454091