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Caulfield A, Hamilton WL, Trent L, Ellington M. Clinical predictors of specialist treatment requirements in pelvic fracture: A retrospective cohort study. TRAUMA-ENGLAND 2018. [DOI: 10.1177/1460408617725105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objectives and background To describe the pelvic fracture population presenting to a district hospital in New Zealand and investigate whether clinical measurements can predict subsequent transfer to specialist tertiary care units. Early transfer to tertiary care is associated with improved surgical outcomes and cost-effectiveness, but there has as yet been little research into predictive markers for referral. Methods Retrospective cohort study of all patients admitted with pelvic fracture to the intensive care unit of Hastings Memorial Hospital, New Zealand from 2005 to 2014. The primary outcome was transfer to specialist tertiary care. Secondary outcomes were total duration of hospitalisation and conservative vs. surgical management. Clinical variables including age, sex, observations and comorbidities were analysed against these outcomes using logistic regression. Results Data from 40 patients were collected (24 male, 16 female; median age: 44 years). Median distance from the hospital was 22.6 km, with 27 (67.5%) patients transported by land and 13 (32.5%) arriving by helicopter. Median time from receipt of emergency call to arrival at hospital was 60 min. Three patients died and 14/40 (35%) required transfer to tertiary centres. Damage to intra-abdominal structures such as spleen, liver and bladder lacerations were associated with transfer to tertiary care, unadjusted relative risk 3.34 (95% confidence intervals: 1.39–8.05). Conclusion Despite a 10-year recruitment window, only 40 patients were included in this study, limiting its statistical power. Nonetheless, our data suggest that pelvic fracture patients with injuries to intra-abdominal viscera are more likely to require tertiary care transfer.
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Otto TD, Böhme U, Sanders M, Reid A, Bruske EI, Duffy CW, Bull PC, Pearson RD, Abdi A, Dimonte S, Stewart LB, Campino S, Kekre M, Hamilton WL, Claessens A, Volkman SK, Ndiaye D, Amambua-Ngwa A, Diakite M, Fairhurst RM, Conway DJ, Franck M, Newbold CI, Berriman M. Long read assemblies of geographically dispersed Plasmodium falciparum isolates reveal highly structured subtelomeres. Wellcome Open Res 2018; 3:52. [PMID: 29862326 PMCID: PMC5964635 DOI: 10.12688/wellcomeopenres.14571.1] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/27/2018] [Indexed: 12/30/2022] Open
Abstract
Background: Although thousands of clinical isolates of
Plasmodium falciparum are being sequenced and analysed by short read technology, the data do not resolve the highly variable subtelomeric regions of the genomes that contain polymorphic gene families involved in immune evasion and pathogenesis. There is also no current standard definition of the boundaries of these variable subtelomeric regions. Methods: Using long-read sequence data (Pacific Biosciences SMRT technology), we assembled and annotated the genomes of 15
P. falciparum isolates, ten of which are newly cultured clinical isolates. We performed comparative analysis of the entire genome with particular emphasis on the subtelomeric regions and the internal
var genes clusters.
Results: The nearly complete sequence of these 15 isolates has enabled us to define a highly conserved core genome, to delineate the boundaries of the subtelomeric regions, and to compare these across isolates. We found highly structured variable regions in the genome. Some exported gene families purportedly involved in release of merozoites show copy number variation. As an example of ongoing genome evolution, we found a novel CLAG gene in six isolates. We also found a novel gene that was relatively enriched in the South East Asian isolates compared to those from Africa. Conclusions: These 15 manually curated new reference genome sequences with their nearly complete subtelomeric regions and fully assembled genes are an important new resource for the malaria research community. We report the overall conserved structure and pattern of important gene families and the more clearly defined subtelomeric regions.
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Hamilton WL, Agranoff D. Imported gnathostomiasis manifesting as cutaneous larva migrans and Löffler's syndrome. BMJ Case Rep 2018; 2018:bcr-2017-223132. [PMID: 29420245 PMCID: PMC5812380 DOI: 10.1136/bcr-2017-223132] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/11/2018] [Indexed: 11/03/2022] Open
Abstract
Here, we report an unusual case of invasive gnathostomiasis in a returning traveller, with a shifting pattern of relapsing cutaneous disease. The previously fit and well 32-year-old man first presented with serpiginous, pruriginous erythematous tracks characteristic of cutaneous larva migrans shortly after returning from South-East Asia. He was systemically well with no other symptoms. After ivermectin therapy, he re-presented with respiratory symptoms, peripheral eosinophilia and transient pulmonary infiltrates; the classic triad of Löffler's syndrome associated with invasive helminth infection. Gnathostoma spinigerum immunoblot was positive. After a second round of ivermectin therapy his respiratory symptoms resolved, but the patient's cutaneous disease relapsed repeatedly over months, with migratory erythematous swellings appearing and settling after a few days. He was treated with a 21-day course of albendazole and is lesion free at 40 weeks post initial presentation.
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Hamilton WL, Claessens A, Otto TD, Kekre M, Fairhurst RM, Rayner JC, Kwiatkowski D. Extreme mutation bias and high AT content in Plasmodium falciparum. Nucleic Acids Res 2017; 45:1889-1901. [PMID: 27994033 PMCID: PMC5389722 DOI: 10.1093/nar/gkw1259] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 12/01/2016] [Indexed: 01/31/2023] Open
Abstract
For reasons that remain unknown, the Plasmodium falciparum genome has an exceptionally high AT content compared to other Plasmodium species and eukaryotes in general - nearly 80% in coding regions and approaching 90% in non-coding regions. Here, we examine how this phenomenon relates to genome-wide patterns of de novo mutation. Mutation accumulation experiments were performed by sequential cloning of six P. falciparum isolates growing in human erythrocytes in vitro for 4 years, with 279 clones sampled for whole genome sequencing at different time points. Genome sequence analysis of these samples revealed a significant excess of G:C to A:T transitions compared to other types of nucleotide substitution, which would naturally cause AT content to equilibrate close to the level seen across the P. falciparum reference genome (80.6% AT). These data also uncover an extremely high rate of small indel mutation relative to other species, primarily associated with repetitive AT-rich sequences, in addition to larger-scale structural rearrangements focused in antigen-coding var genes. In conclusion, high AT content in P. falciparum is driven by a systematic mutational bias and ultimately leads to an unusual level of microstructural plasticity, raising the question of whether this contributes to adaptive evolution.
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Zhang J, Hamilton WL, Danescu-Niculescu-Mizil C, Jurafsky D, Leskovec J. Community Identity and User Engagement in a Multi-Community Landscape. PROCEEDINGS OF THE ... INTERNATIONAL AAAI CONFERENCE ON WEBLOGS AND SOCIAL MEDIA. INTERNATIONAL AAAI CONFERENCE ON WEBLOGS AND SOCIAL MEDIA 2017; 2017:377-386. [PMID: 29354325 PMCID: PMC5774974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A community's identity defines and shapes its internal dynamics. Our current understanding of this interplay is mostly limited to glimpses gathered from isolated studies of individual communities. In this work we provide a systematic exploration of the nature of this relation across a wide variety of online communities. To this end we introduce a quantitative, language-based typology reflecting two key aspects of a community's identity: how distinctive, and how temporally dynamic it is. By mapping almost 300 Reddit communities into the landscape induced by this typology, we reveal regularities in how patterns of user engagement vary with the characteristics of a community. Our results suggest that the way new and existing users engage with a community depends strongly and systematically on the nature of the collective identity it fosters, in ways that are highly consequential to community maintainers. For example, communities with distinctive and highly dynamic identities are more likely to retain their users. However, such niche communities also exhibit much larger acculturation gaps between existing users and newcomers, which potentially hinder the integration of the latter. More generally, our methodology reveals differences in how various social phenomena manifest across communities, and shows that structuring the multi-community landscape can lead to a better understanding of the systematic nature of this diversity.
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Hamilton WL, Zhang J, Danescu-Niculescu-Mizil C, Jurafsky D, Leskovec J. Loyalty in Online Communities. PROCEEDINGS OF THE ... INTERNATIONAL AAAI CONFERENCE ON WEBLOGS AND SOCIAL MEDIA. INTERNATIONAL AAAI CONFERENCE ON WEBLOGS AND SOCIAL MEDIA 2017; 2017:540-543. [PMID: 29354326 PMCID: PMC5774975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Loyalty is an essential component of multi-community engagement. When users have the choice to engage with a variety of different communities, they often become loyal to just one, focusing on that community at the expense of others. However, it is unclear how loyalty is manifested in user behavior, or whether certain community characteristics encourage loyalty. In this paper we operationalize loyalty as a user-community relation: users loyal to a community consistently prefer it over all others; loyal communities retain their loyal users over time. By exploring a large set of Reddit communities, we reveal that loyalty is manifested in remarkably consistent behaviors. Loyal users employ language that signals collective identity and engage with more esoteric, less popular content, indicating that they may play a curational role in surfacing new material. Loyal communities have denser user-user interaction networks and lower rates of triadic closure, suggesting that community-level loyalty is associated with more cohesive interactions and less fragmentation into subgroups. We exploit these general patterns to predict future rates of loyalty. Our results show that a user's propensity to become loyal is apparent from their initial interactions with a community, suggesting that some users are intrinsically loyal from the very beginning.
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Oyola SO, Ariani CV, Hamilton WL, Kekre M, Amenga-Etego LN, Ghansah A, Rutledge GG, Redmond S, Manske M, Jyothi D, Jacob CG, Otto TD, Rockett K, Newbold CI, Berriman M, Kwiatkowski DP. Whole genome sequencing of Plasmodium falciparum from dried blood spots using selective whole genome amplification. Malar J 2016; 15:597. [PMID: 27998271 PMCID: PMC5175302 DOI: 10.1186/s12936-016-1641-7] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 11/28/2016] [Indexed: 12/05/2022] Open
Abstract
Background Translating genomic technologies into healthcare applications for the malaria parasite Plasmodium falciparum has been limited by the technical and logistical difficulties of obtaining high quality clinical samples from the field. Sampling by dried blood spot (DBS) finger-pricks can be performed safely and efficiently with minimal resource and storage requirements compared with venous blood (VB). Here, the use of selective whole genome amplification (sWGA) to sequence the P. falciparum genome from clinical DBS samples was evaluated, and the results compared with current methods that use leucodepleted VB. Methods Parasite DNA with high (>95%) human DNA contamination was selectively amplified by Phi29 polymerase using short oligonucleotide probes of 8–12 mers as primers. These primers were selected on the basis of their differential frequency of binding the desired (P. falciparum DNA) and contaminating (human) genomes. Results Using sWGA method, clinical samples from 156 malaria patients, including 120 paired samples for head-to-head comparison of DBS and leucodepleted VB were sequenced. Greater than 18-fold enrichment of P. falciparum DNA was achieved from DBS extracts. The parasitaemia threshold to achieve >5× coverage for 50% of the genome was 0.03% (40 parasites per 200 white blood cells). Over 99% SNP concordance between VB and DBS samples was achieved after excluding missing calls. Conclusion The sWGA methods described here provide a reliable and scalable way of generating P. falciparum genome sequence data from DBS samples. The current data indicate that it will be possible to get good quality sequence on most if not all drug resistance loci from the majority of symptomatic malaria patients. This technique overcomes a major limiting factor in P. falciparum genome sequencing from field samples, and paves the way for large-scale epidemiological applications. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1641-7) contains supplementary material, which is available to authorized users.
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Hamilton WL, Clark K, Leskovec J, Jurafsky D. Inducing Domain-Specific Sentiment Lexicons from Unlabeled Corpora. PROCEEDINGS OF THE CONFERENCE ON EMPIRICAL METHODS IN NATURAL LANGUAGE PROCESSING. CONFERENCE ON EMPIRICAL METHODS IN NATURAL LANGUAGE PROCESSING 2016; 2016:595-605. [PMID: 28660257 PMCID: PMC5483533 DOI: 10.18653/v1/d16-1057] [Citation(s) in RCA: 133] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
A word's sentiment depends on the domain in which it is used. Computational social science research thus requires sentiment lexicons that are specific to the domains being studied. We combine domain-specific word embeddings with a label propagation framework to induce accurate domain-specific sentiment lexicons using small sets of seed words. We show that our approach achieves state-of-the-art performance on inducing sentiment lexicons from domain-specific corpora and that our purely corpus-based approach outperforms methods that rely on hand-curated resources (e.g., WordNet). Using our framework, we induce and release historical sentiment lexicons for 150 years of English and community-specific sentiment lexicons for 250 online communities from the social media forum Reddit. The historical lexicons we induce show that more than 5% of sentiment-bearing (non-neutral) English words completely switched polarity during the last 150 years, and the community-specific lexicons highlight how sentiment varies drastically between different communities.
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Hamilton WL, Doyle C, Halliwell-Ewen M, Lambert G. Public health interventions to protect against falsified medicines: a systematic review of international, national and local policies. Health Policy Plan 2016; 31:1448-1466. [PMID: 27311827 DOI: 10.1093/heapol/czw062] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/17/2016] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Falsified medicines are deliberately fraudulent drugs that pose a direct risk to patient health and undermine healthcare systems, causing global morbidity and mortality. OBJECTIVE To produce an overview of anti-falsifying public health interventions deployed at international, national and local scales in low and middle income countries (LMIC). DATA SOURCES We conducted a systematic search of the PubMed, Web of Science, Embase and Cochrane Central Register of Controlled Trials databases for healthcare or pharmaceutical policies relevant to reducing the burden of falsified medicines in LMIC. RESULTS Our initial search identified 660 unique studies, of which 203 met title/abstract inclusion criteria and were categorised according to their primary focus: international; national; local pharmacy; internet pharmacy; drug analysis tools. Eighty-four were included in the qualitative synthesis, along with 108 articles and website links retrieved through secondary searches. DISCUSSION On the international stage, we discuss the need for accessible pharmacovigilance (PV) global reporting systems, international leadership and funding incorporating multiple stakeholders (healthcare, pharmaceutical, law enforcement) and multilateral trade agreements that emphasise public health. On the national level, we explore the importance of establishing adequate medicine regulatory authorities and PV capacity, with drug screening along the supply chain. This requires interdepartmental coordination, drug certification and criminal justice legislation and enforcement that recognise the severity of medicine falsification. Local healthcare professionals can receive training on medicine quality assessments, drug registration and pharmacological testing equipment. Finally, we discuss novel technologies for drug analysis which allow rapid identification of fake medicines in low-resource settings. Innovative point-of-purchase systems like mobile phone verification allow consumers to check the authenticity of their medicines. CONCLUSIONS Combining anti-falsifying strategies targeting different levels of the pharmaceutical supply chain provides multiple barriers of protection from falsified medicines. This requires the political will to drive policy implementation; otherwise, people around the world remain at risk.
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Freedman SB, Xie J, Neufeld MS, Hamilton WL, Hartling L, Tarr PI, Nettel-Aguirre A, Chuck A, Lee B, Johnson D, Currie G, Talbot J, Jiang J, Dickinson J, Kellner J, MacDonald J, Svenson L, Chui L, Louie M, Lavoie M, Eltorki M, Vanderkooi O, Tellier R, Ali S, Drews S, Graham T, Pang XL. Shiga Toxin-Producing Escherichia coli Infection, Antibiotics, and Risk of Developing Hemolytic Uremic Syndrome: A Meta-analysis. Clin Infect Dis 2016; 62:1251-1258. [PMID: 26917812 DOI: 10.1093/cid/ciw099] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 01/13/2016] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Antibiotic administration to individuals with Shiga toxin-producing Escherichia coli (STEC) infection remains controversial. We assessed if antibiotic administration to individuals with STEC infection is associated with development of hemolytic uremic syndrome (HUS). METHODS The analysis included studies published up to 29 April 2015, that provided data from patients (1) with STEC infection, (2) who received antibiotics, (3) who developed HUS, and (4) for whom data reported timing of antibiotic administration in relation to HUS. Risk of bias was assessed; strength of evidence was adjudicated. HUS was the primary outcome. Secondary outcomes restricted the analysis to low-risk-of-bias studies employing commonly used HUS criteria. Pooled estimates of the odds ratio (OR) were obtained using random-effects models. RESULTS Seventeen reports and 1896 patients met eligibility; 8 (47%) studies were retrospective, 5 (29%) were prospective cohort, 3 (18%) were case-control, and 1 was a trial. The pooled OR, including all studies, associating antibiotic administration and development of HUS was 1.33 (95% confidence interval [CI], .89-1.99; I(2) = 42%). The repeat analysis including only studies with a low risk of bias and those employing an appropriate definition of HUS yielded an OR of 2.24 (95% CI, 1.45-3.46; I(2) = 0%). CONCLUSIONS Overall, use of antibiotics was not associated with an increased risk of developing HUS; however, after excluding studies at high risk of bias and those that did not employ an acceptable definition of HUS, there was a significant association. Consequently, the use of antibiotics in individuals with STEC infections is not recommended.
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Claessens A, Hamilton WL, Kekre M, Otto TD, Faizullabhoy A, Rayner JC, Kwiatkowski D. Generation of antigenic diversity in Plasmodium falciparum by structured rearrangement of Var genes during mitosis. PLoS Genet 2014; 10:e1004812. [PMID: 25521112 PMCID: PMC4270465 DOI: 10.1371/journal.pgen.1004812] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 10/08/2014] [Indexed: 11/25/2022] Open
Abstract
The most polymorphic gene family in P. falciparum is the ∼60 var genes distributed across parasite chromosomes, both in the subtelomeres and in internal regions. They encode hypervariable surface proteins known as P. falciparum erythrocyte membrane protein 1 (PfEMP1) that are critical for pathogenesis and immune evasion in Plasmodium falciparum. How var gene sequence diversity is generated is not currently completely understood. To address this, we constructed large clone trees and performed whole genome sequence analysis to study the generation of novel var gene sequences in asexually replicating parasites. While single nucleotide polymorphisms (SNPs) were scattered across the genome, structural variants (deletions, duplications, translocations) were focused in and around var genes, with considerable variation in frequency between strains. Analysis of more than 100 recombination events involving var exon 1 revealed that the average nucleotide sequence identity of two recombining exons was only 63% (range: 52.7–72.4%) yet the crossovers were error-free and occurred in such a way that the resulting sequence was in frame and domain architecture was preserved. Var exon 1, which encodes the immunologically exposed part of the protein, recombined in up to 0.2% of infected erythrocytes in vitro per life cycle. The high rate of var exon 1 recombination indicates that millions of new antigenic structures could potentially be generated each day in a single infected individual. We propose a model whereby var gene sequence polymorphism is mainly generated during the asexual part of the life cycle. Malaria kills >600,000 people each year, with most deaths caused by Plasmodium falciparum. A family of proteins known as P. falciparum erythrocyte membrane protein 1, PfEMP1, is expressed on the surface of infected erythrocytes and plays an important role in pathogenesis. Each P. falciparum genome contains approximately 60 highly polymorphic var genes encoding the PfEMP1 proteins, and monoallelic expression with periodic switching results in immune evasion. Var gene polymorphism is thus critical to this survival strategy. We investigated how var gene diversity is generated by performing an in vitro evolution experiment, tracking var gene mutation in ‘real-time’ with whole genome sequencing. We found that genome structural variation is focused in and around var genes. These genetic rearrangements created new ‘chimeric’ var gene sequences during the mitotic part of the life cycle, and were consistent with processes of mitotic non-allelic homologous recombination. The recombinant var genes were always in frame and with conserved overall var gene architecture, and the recombination rate implies that many millions of rearranged var gene sequences are produced every 48-hour life cycle within infected individuals. In conclusion, we provide a detailed description of how new var gene sequences are continuously generated in the parasite genome, helping to explain long-term parasite survival within infected human hosts.
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Oyola SO, Manske M, Campino S, Claessens A, Hamilton WL, Kekre M, Drury E, Mead D, Gu Y, Miles A, MacInnis B, Newbold C, Berriman M, Kwiatkowski DP. Optimized whole-genome amplification strategy for extremely AT-biased template. DNA Res 2014; 21:661-71. [PMID: 25240466 PMCID: PMC4263299 DOI: 10.1093/dnares/dsu028] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Pathogen genome sequencing directly from clinical samples is quickly gaining importance in genetic and medical research studies. However, low DNA yield from blood-borne pathogens is often a limiting factor. The problem worsens in extremely base-biased genomes such as the AT-rich Plasmodium falciparum. We present a strategy for whole-genome amplification (WGA) of low-yield samples from P. falciparum prior to short-read sequencing. We have developed WGA conditions that incorporate tetramethylammonium chloride for improved amplification and coverage of AT-rich regions of the genome. We show that this method reduces amplification bias and chimera formation. Our data show that this method is suitable for as low as 10 pg input DNA, and offers the possibility of sequencing the parasite genome from small blood samples.
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Uchil PD, Pawliczek T, Reynolds TD, Ding S, Hinz A, Munro JB, Huang F, Floyd RW, Yang H, Hamilton WL, Bewersdorf J, Xiong Y, Calderwood DA, Mothes W. TRIM15 is a focal adhesion protein that regulates focal adhesion disassembly. J Cell Sci 2014; 127:3928-42. [PMID: 25015296 DOI: 10.1242/jcs.143537] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Focal adhesions are macromolecular complexes that connect the actin cytoskeleton to the extracellular matrix. Dynamic turnover of focal adhesions is crucial for cell migration. Paxillin is a multi-adaptor protein that plays an important role in regulating focal adhesion dynamics. Here, we identify TRIM15, a member of the tripartite motif protein family, as a paxillin-interacting factor and a component of focal adhesions. TRIM15 localizes to focal contacts in a myosin-II-independent manner by an interaction between its coiled-coil domain and the LD2 motif of paxillin. Unlike other focal adhesion proteins, TRIM15 is a stable focal adhesion component with restricted mobility due to its ability to form oligomers. TRIM15-depleted cells display impaired cell migration and reduced focal adhesion disassembly rates, in addition to enlarged focal adhesions. Thus, our studies demonstrate a cellular function for TRIM15 as a regulatory component of focal adhesion turnover and cell migration.
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Biener L, Hamilton WL, Siegel M, Sullivan EM. Individual, social-normative, and policy predictors of smoking cessation: a multilevel longitudinal analysis. Am J Public Health 2009; 100:547-54. [PMID: 19696387 DOI: 10.2105/ajph.2008.150078] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES We assessed the prospective impact of individual, social-normative, and policy predictors of quit attempts and smoking cessation among Massachusetts adults. METHODS We interviewed a representative sample of current and recent smokers in Massachusetts by telephone in 2001 through 2002 and then again twice at 2-year intervals. The unit of analysis was the 2-year transition from wave 1 to wave 2 and from wave 2 to wave 3. Predictors of quit attempts and abstinence of longer than 3 months were analyzed using multilevel analysis. Predictors included individual, social-normative, and policy factors. RESULTS Multivariate analyses of 2-year transitions showed that perceptions of strong antismoking town norms were predictive of abstinence (odds ratio = 2.06; P < .01). Household smoking bans were the only policy associated with abstinence, but smoking bans at one's worksite were significant predictors of quit attempts. CONCLUSIONS Although previous research showed a strong relation between local policy and norms, we found no observable, prospective impact of local policy on smoking cessation over 2 years. Our findings provide clear support for the importance of strong antismoking social norms as a facilitator of smoking cessation.
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Hamilton WL, Biener L, Brennan RT. Do local tobacco regulations influence perceived smoking norms? Evidence from adult and youth surveys in Massachusetts. HEALTH EDUCATION RESEARCH 2008; 23:709-722. [PMID: 17947246 PMCID: PMC2733799 DOI: 10.1093/her/cym054] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2007] [Accepted: 07/09/2007] [Indexed: 05/25/2023]
Abstract
Smoking behavior has been shown to be influenced by individuals' perceptions of social norms about smoking. This study examines whether local regulations regarding clean indoor air and youth access to tobacco are associated with residents' subsequent perceptions of smoking norms. Data came from Massachusetts surveys of adults and youths and from records of local tobacco control policies. Indices of perceived smoking norms were based on perceived smoking prevalence and perceived community acceptance of smoking. Multilevel models tested the association between perceived norms and the presence of strong local regulations in four policy domains (restaurant smoking bans, smoking restrictions in other venues, enforcement of laws prohibiting sales to youths and youth-oriented marketing restrictions). The model controlled for town voting results on a tobacco tax referendum, which served as a measure of antismoking sentiment pre-dating the regulations. Results showed that youths perceived community norms to be significantly more 'antismoking' if they lived in a town that had strong regulations in at least three of the four domains. For adults, having strong regulations in as few as one to two domains was associated with perceiving community norms to be significantly more antismoking. Implementing and publicizing local regulations may help shape perceptions of community smoking norms.
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Siegel M, Albers AB, Cheng DM, Hamilton WL, Biener L. Local restaurant smoking regulations and the adolescent smoking initiation process: results of a multilevel contextual analysis among Massachusetts youth. ACTA ACUST UNITED AC 2008; 162:477-83. [PMID: 18458195 DOI: 10.1001/archpedi.162.5.477] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To assess whether smoke-free restaurant laws influence the progression from (1) never smoking to early experimentation and (2) early experimentation to established smoking. DESIGN A longitudinal, 4-year, 3-wave study of a representative sample of Massachusetts youth. SETTING A total of 301 Massachusetts communities. PARTICIPANTS Study participants were 3834 Massachusetts youths aged 12 to 17 years at baseline, from January 2, 2001, to June 18, 2002, of whom 2791 (72.8%) were reinterviewed after 2 years (from January 30, 2003, to July 31, 2004) and 2217 (57.8%) were reinterviewed after 4 years (from February 16, 2005, to March 26, 2006). Wave 3 respondents were recruited from both those who responded at wave 2 and those who did not. MAIN EXPOSURE The primary predictor of interest is the strength of the local restaurant smoking regulation in the respondents' town of residence at the baseline of each transition period. MAIN OUTCOME MEASURES (1) Overall progression to established smoking (having smoked > or =100 cigarettes in one's lifetime), (2) transition from nonsmoking (never having puffed a cigarette) to experimentation, and (3) transition from experimentation to established smoking. RESULTS Youths living in towns with a strong restaurant smoking regulation at baseline had significantly lower odds of progressing to established smoking (odds ratio, 0.60; 95% confidence interval, 0.42-0.85) compared with those living in towns with weak regulations. The observed association between strong restaurant smoking regulations and impeded progression to established smoking was entirely due to an effect on the transition from experimentation to established smoking (odds ratio, 0.53; 95% confidence interval, 0.33-0.86). CONCLUSION Local smoke-free restaurant laws may significantly lower youth smoking initiation by impeding the progression from cigarette experimentation to established smoking.
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Thomson CC, Hamilton WL, Siegel MB, Biener L, Rigotti NA. Effect of local youth-access regulations on progression to established smoking among youths in Massachusetts. Tob Control 2007; 16:119-26. [PMID: 17400950 PMCID: PMC2598482 DOI: 10.1136/tc.2006.018002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2006] [Accepted: 10/23/2006] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To test whether community-level restrictions on youth access to tobacco (including both ordinances and enforcement) are associated with less smoking initiation or less progression to established smoking among adolescents. DESIGN Prospective cohort study of a random sample of adolescents in Massachusetts whose smoking status was assessed by telephone interviews at baseline and 2-year follow-up, and linked to a state-wide database of town-level youth-access ordinances and enforcement practices. PARTICIPANTS A random sample of 2623 adolescents aged 12-17 years who lived in 295 towns in Massachusetts in 2001-2 and were followed in 2003-4. MAIN OUTCOME MEASURES The relationship between the strength of local youth access restrictions (including both ordinances and level of enforcement) and (1) never-smokers' smoking initiation rates and (2) experimenters' rate of progression to established smoking was tested in a multilevel analysis that accounted for town-level clustering and adjusted for potential individual, household and town-level confounders. RESULTS Over 2 years, 21% of 1986 never-smokers initiated smoking and 25% of 518 experimenters became established smokers. The adjusted odds ratio (OR) for smoking initiation was 0.89 (95% CI 0.61 to 1.31) for strong versus weak youth-access policies and 0.93 (95% CI 0.67 to 1.29) for medium versus weak policies. The adjusted OR for progression to established smoking among adolescents who had experimented with smoking was 0.79 (95% CI 0.45 to 1.39) for strong versus weak local smoking restrictions and 0.85 (95% CI 0.50 to 1.45) for medium versus weak restrictions. CONCLUSIONS This prospective cohort study found no association between community-level youth-access restrictions and adolescents' rate of smoking initiation or progression to established smoking over 2 years.
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Hamilton WL, Biener L, Rodger CN. Who supports tobacco excise taxes? Factors associated with towns' and individuals' support in Massachusetts. JOURNAL OF PUBLIC HEALTH MANAGEMENT AND PRACTICE 2005; 11:333-40. [PMID: 15958933 DOI: 10.1097/00124784-200507000-00012] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES The authors examined factors related to public support for cigarette taxes: smoking behavior, attitudes about other tobacco control policies, and sociodemographic factors. METHODS The authors regressed referendum voting outcomes on sociodemographic characteristics of Massachusetts' 351 towns. Logistic regressions on the surveys of Massachusetts adults (N = 14,000+) showed support for hypothetical tax increases to be related to respondents' smoking status, support for other tobacco control policies, and sociodemographic characteristics. RESULTS Average educational attainment, probably acting as a proxy for nonsmoking prevalence, strongly predicted town-level support for Massachusetts' 1992 cigarette tax referendum. Survey respondents' support for hypothetical further increases was strongest if tax proceeds were earmarked for tobacco control or health purposes and if the individual was a nonsmoker and favored other tobacco control policies. For an earmarked tax, support was stronger among younger persons, females, persons with higher education, racial/ethnic minorities, and smokers with children. CONCLUSIONS The high nationwide proportion of nonsmokers means that tobacco tax proposals can obtain strong voter support, but only if tax revenues are clearly earmarked for tobacco control and similar uses. Individual- and town-level characteristics can identify likely concentrations of support. Because attitudes toward tobacco control are only partly linked to smoking status, education campaigns may make a difference.
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Hamilton WL, Norton GD, Ouellette TK, Rhodes WM, Kling R, Connolly GN. Smokers' responses to advertisements for regular and light cigarettes and potential reduced-exposure tobacco products. Nicotine Tob Res 2005; 6 Suppl 3:S353-62. [PMID: 15799598 DOI: 10.1080/14622200412331320752] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
This study examines smokers' responses to advertisements for potentially reduced exposure tobacco products (PREP), light cigarettes, and regular cigarettes. A convenience sample of 600 adult smokers reviewed one actual advertisement for each type of product. Smokers ranked the products on health risk, amount of tar, and carcinogenicity, and identified the messages they perceived the advertisements to convey. Smokers perceived PREP products as having lower health risks (mean = 5.4 on a scale of 1-10) and carcinogens (6.6) than light cigarettes (5.8 and 6.9, respectively, p < .001), and lights as having lower health risks and carcinogen levels than regular cigarettes (8.2 and 8.8, respectively, p <.001). The average PREP rating for level of tar (5.3) was not significantly less than the light mean of 5.4, but both were significantly less than the regular mean of 8.4 (p <.001). Although no advertisements explicitly said that the products were healthy or safe, advertisements for PREP products and light cigarettes were interpreted as conveying positive messages about health and safety. Most smokers believed that claims made in cigarette advertisements must be approved by a government agency. The results indicate that advertisements can and do leave consumers with perceptions of the health and safety of tobacco products that are contrary to the scientific evidence. Explicit and implicit advertising messages may be strengthened by the perceived government endorsement. This supports the Institute of Medicine's recommendation to regulate the promotion, advertising, and labeling of PREP tobacco products and light cigarettes. Effective regulation may need to focus on consumer perceptions resulting from advertisements rather than the explicit content of advertising text.
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Skeer M, George S, Hamilton WL, Cheng DM, Siegel M. Town-level characteristics and smoking policy adoption in Massachusetts: are local restaurant smoking regulations fostering disparities in health protection? Am J Public Health 2004; 94:286-92. [PMID: 14759944 PMCID: PMC1448245 DOI: 10.2105/ajph.94.2.286] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/24/2003] [Indexed: 11/04/2022]
Abstract
OBJECTIVES We identified and quantified differences in sociodemographic characteristics of communities relative to the strength of local restaurant smoking regulations in Massachusetts. METHODS We examined the relationship between the strength of the 351 local restaurant smoking regulations in Massachusetts and a number of town-level characteristics, using a multinomial logistic regression model. RESULTS Characteristics important to the adoption of stronger restaurant smoking regulations included higher education and per capita income, geographic region, voter support for a state cigarette tax initiative, board of health funding to promote clean indoor air policy making, and the presence of a bordering town with a strong regulation. CONCLUSIONS The current pattern of smoke-free restaurant policy enactment fosters socioeconomic and geographic disparities in health protection, undermining an important national health goal.
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Hamilton WL, Turner-Bowker DM, Celebucki CC, Connolly GN. Cigarette advertising in magazines: the tobacco industry response to the Master Settlement Agreement and to public pressure. Tob Control 2002; 11 Suppl 2:ii54-8. [PMID: 12034983 PMCID: PMC1766075 DOI: 10.1136/tc.11.suppl_2.ii54] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE The Master Settlement Agreement (MSA) of November 1998 prohibited participating tobacco companies from directly or indirectly targeting youth in marketing. Widely publicised information in May 2000 showed increased cigarette advertising in magazines with substantial youth readership and companies were pressed to change their practices. The responses of the tobacco industry to the MSA and to the public pressure are examined. DESIGN Expenditures on cigarette advertisements in national magazines in the USA are compared for three periods: January to November 1998, December 1998 to June 2000, and July 2000 to November 2001. Magazines in which at least 15% of readers are youth under age 18 are focused upon. Regression models test for the significance of period differences after controlling for seasonal and long term patterns. DATA SOURCES Commercially maintained data on advertising in US magazines and on magazine readership by age. KEY MEASURES Monthly cigarette ad expenditures in magazines with 15%+ youth readership, and monthly proportion of ad expenditures in 15%+ youth magazines. RESULTS Cigarette advertising expenditures in magazines with 15%+ youth readership increased dramatically after MSA implementation and fell dramatically after public pressure. The percentage allocation of expenditures to 15%+ magazines fell significantly in both periods. Results differ somewhat by company. CONCLUSIONS The tobacco industry response to the MSA was at best modest, reducing proportional allocations of advertising to youth magazines but increasing the absolute amount of such advertising. The value of public pressure was seen in substantial reductions in both absolute and proportional spending on youth magazines, although not by all companies.
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Truitt L, Hamilton WL, Johnston PR, Bacani CP, Crawford SO, Hozik L, Celebucki C. Recall of health warnings in smokeless tobacco ads. Tob Control 2002; 11 Suppl 2:ii59-63. [PMID: 12034984 PMCID: PMC1766072 DOI: 10.1136/tc.11.suppl_2.ii59] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To determine the effects of health warning characteristics in smokeless tobacco magazine print ads on warning recall, and the implications for current US Federal regulations. DESIGN Subjects examined two distracter ads and one of nine randomly assigned smokeless tobacco ads varying in health warning presence, size (8 to 18 point font), and contrast (low versus high)-including no health warning. They were then interviewed about ad content using recall and recognition questions. SUBJECTS A convenience sample of 895 English speaking males aged 16-24 years old who were intercepted at seven shopping malls throughout Massachusetts during May 2000. MAIN OUTCOME MEASURES Proven aided recall, or recall of a health warning and correct recognition of the warning message among distracters, and false recall. RESULTS Controlling for covariates such as education, employment/student status, and Hispanic background, proven aided recall increased significantly with font size; doubling size from 10 to 20 point font would increase recall from 63% to 76%. Although not statistically significant, recall was somewhat better for high contrast warnings. Ten per cent of the sample mistakenly recalled the warning where none existed. CONCLUSIONS As demonstrated by substantially greater recall among ads that included health warnings over ads that had none, health warnings retained their value to consumers despite years of exposure (that can produce false recall). Larger health warnings would enhance recall, and the proposed model can be used to estimate potential recall that affects communication, perceived health risk, and behaviour modification.
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Weintraub JM, Hamilton WL. Trends in prevalence of current smoking, Massachusetts and states without tobacco control programmes, 1990 to 1999. Tob Control 2002; 11 Suppl 2:ii8-13. [PMID: 12034974 PMCID: PMC1766078 DOI: 10.1136/tc.11.suppl_2.ii8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To assess the effect of a comprehensive tobacco control programme initiated in Massachusetts in 1993, and to compare the 1990 to 1999 trend in smoking prevalence to that in 41 states without tobacco control programmes, controlling for demographic shifts over time. DESIGN Data from the Behavioral Risk Factor Surveillance System for the years 1990 to 1999 were used to examine changes and trends in prevalence of smoking using multivariate logistic regression models. MAIN OUTCOME MEASURES Trend in prevalence of current smoking for the years 1990 to 1999. RESULTS In 1990, the prevalence of current smoking in Massachusetts was 23.5% (95% confidence interval (CI) 21.0% to 26.1%), and 24.2% in the rest of the USA (95% CI 23.7% to 24.7%). By 1999, the prevalence had declined in Massachusetts to 19.4%, and to 23.3% in 41 other US states. Controlling for sex, age, race, and education, there was a greater decline in current smoking between 1990 and 1999 among Massachusetts men than among Massachusetts women, and the decline was greater in Massachusetts than in the rest of the USA for men and for both sexes combined. CONCLUSIONS These results suggest that the Massachusetts Tobacco Control Program is having a beneficial impact, but suggest a need for additional targeted efforts to achieve similar declines among Massachusetts women.
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Blumberg SJ, Bialostosky K, Hamilton WL, Briefel RR. The effectiveness of a short form of the Household Food Security Scale. Am J Public Health 1999; 89:1231-4. [PMID: 10432912 PMCID: PMC1508674 DOI: 10.2105/ajph.89.8.1231] [Citation(s) in RCA: 584] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES On the basis of an 18-item Household Food Security Scale, a short form was developed to assess financially based food insecurity and hunger in surveys of households with and without children. METHODS To maximize the probability that households would be correctly classified with respect to food insecurity and hunger, 6 items from the full scale were selected on the basis of April 1995 Current Population Survey data. RESULTS The short form classified 97.7% of households correctly and underestimated the prevalence of overall food insecurity and of hunger by 0.3 percentage points. CONCLUSIONS The short form of the Household Food Security Scale is a brief but potentially useful tool for national surveys and some state/local applications.
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Matsumura KN, Guevara GR, Huston H, Hamilton WL, Rikimaru M, Yamasaki G, Matsumura MS. Hybrid bioartificial liver in hepatic failure: preliminary clinical report. Surgery 1987; 101:99-103. [PMID: 3798332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A hybrid bioartificial liver has been developed on the principle of hemodialysis against a suspension of functioning hepatocytes. The new chimeric device of synthetics and living parts was used successfully to treat a patient in hepatic failure due to an inoperable bile duct carcinoma that involved the bifurcation of the common duct.
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