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1.
Angew Chem Int Ed Engl ; 61(29): e202203067, 2022 07 18.
Article in English | MEDLINE | ID: mdl-35445525

ABSTRACT

The synthesis of complementary strands is the reaction underlying the replication of genetic information. It is likely that the earliest self-replicating systems used RNA as genetic material. How RNA was copied in the absence of enzymes and what sequences were most likely to have supported replication is not clear. Here we show that mixtures of dinucleotides with C and G as bases copy an RNA sequence of up to 12 nucleotides in dilute aqueous solution. Successful enzyme-free copying occurred with in situ activation at 4 °C and pH 6.0. Dimers were incorporated in favor of monomers when both competed as reactants, and little misincorporation was detectable in mass spectra. Simulations using experimental rate constants confirmed that mixed C/G sequences are good candidates for successful replication with dimers. Because dimers are intermediates in the synthesis of longer strands, our results support evolutionary scenarios encompassing formation and copying of RNA strands in enzyme-free fashion.


Subject(s)
Nucleotides , RNA , Dinucleoside Phosphates , Mass Spectrometry , RNA/genetics
2.
Nucleic Acids Res ; 47(8): 3836-3845, 2019 05 07.
Article in English | MEDLINE | ID: mdl-30869145

ABSTRACT

The template-directed formation of phosphodiester bonds between two nucleic acid components is a pivotal process in biology. To induce such a reaction in the absence of enzymes is a challenge. This challenge has been met for the extension of a primer with mononucleotides, but the ligation of short oligonucleotides (dimers or trimers) has proven difficult. Here we report a method for ligating dimers and trimers of ribonucleotides using in situ activation in aqueous buffer. All 16 different dimers and two trimers were tested. Binding studies by NMR showed low millimolar dissociation constants for complexes between representative dimers and hairpins mimicking primer-template duplexes, confirming that a weak template effect is not the cause of the poor ligating properties of these short oligomers. Rather, cyclization was found to compete with ligation, with up to 90% of dimer being converted to the cyclic form during the course of an assay. This side reaction is strongly sequence dependent and more pronounced for dimers than for trimers. Under optimized reaction conditions, high yields were observed with strongly pairing purines at the 3'-terminus. These results show that short oligomers of ribonucleotides are competent reactants in enzyme-free copying.


Subject(s)
RNA/chemistry , Ribonucleotides/chemistry , Base Pairing , Base Sequence , Binding Sites , Binding, Competitive , Cyclization , Dinucleotide Repeats , Kinetics , Nucleic Acid Conformation , Solutions
4.
PLoS Med ; 17(5): e1003084, 2020 05.
Article in English | MEDLINE | ID: mdl-32407380

ABSTRACT

BACKGROUND: The radical cure of Plasmodium vivax and P. ovale requires treatment with primaquine or tafenoquine to clear dormant liver stages. Either drug can induce haemolysis in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency, necessitating screening. The reference diagnostic method for G6PD activity is ultraviolet (UV) spectrophotometry; however, a universal G6PD activity threshold above which these drugs can be safely administered is not yet defined. Our study aimed to quantify assay-based variation in G6PD spectrophotometry and to explore the diagnostic implications of applying a universal threshold. METHODS AND FINDINGS: Individual-level data were pooled from studies that used G6PD spectrophotometry. Studies were identified via PubMed search (25 April 2018) and unpublished contributions from contacted authors (PROSPERO: CRD42019121414). Studies were excluded if they assessed only individuals with known haematological conditions, were family studies, or had insufficient details. Studies of malaria patients were included but analysed separately. Included studies were assessed for risk of bias using an adapted form of the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Repeatability and intra- and interlaboratory variability in G6PD activity measurements were compared between studies and pooled across the dataset. A universal threshold for G6PD deficiency was derived, and its diagnostic performance was compared to site-specific thresholds. Study participants (n = 15,811) were aged between 0 and 86 years, and 44.4% (7,083) were women. Median (range) activity of G6PD normal (G6PDn) control samples was 10.0 U/g Hb (6.3-14.0) for the Trinity assay and 8.3 U/g Hb (6.8-15.6) for the Randox assay. G6PD activity distributions varied significantly between studies. For the 13 studies that used the Trinity assay, the adjusted male median (AMM; a standardised metric of 100% G6PD activity) varied from 5.7 to 12.6 U/g Hb (p < 0.001). Assay precision varied between laboratories, as assessed by variance in control measurements (from 0.1 to 1.5 U/g Hb; p < 0.001) and study-wise mean coefficient of variation (CV) of replicate measures (from 1.6% to 14.9%; p < 0.001). A universal threshold of 100% G6PD activity was defined as 9.4 U/g Hb, yielding diagnostic thresholds of 6.6 U/g Hb (70% activity) and 2.8 U/g Hb (30% activity). These thresholds diagnosed individuals with less than 30% G6PD activity with study-wise sensitivity from 89% (95% CI: 81%-94%) to 100% (95% CI: 96%-100%) and specificity from 96% (95% CI: 89%-99%) to 100% (100%-100%). However, when considering intermediate deficiency (<70% G6PD activity), sensitivity fell to a minimum of 64% (95% CI: 52%-75%) and specificity to 35% (95% CI: 24%-46%). Our ability to identify underlying factors associated with study-level heterogeneity was limited by the lack of availability of covariate data and diverse study contexts and methodologies. CONCLUSIONS: Our findings indicate that there is substantial variation in G6PD measurements by spectrophotometry between sites. This is likely due to variability in laboratory methods, with possible contribution of unmeasured population factors. While an assay-specific, universal quantitative threshold offers robust diagnosis at the 30% level, inter-study variability impedes performance of universal thresholds at the 70% level. Caution is advised in comparing findings based on absolute G6PD activity measurements across studies. Novel handheld quantitative G6PD diagnostics may allow greater standardisation in the future.


Subject(s)
Glucosephosphate Dehydrogenase Deficiency/diagnosis , Glucosephosphate Dehydrogenase Deficiency/metabolism , Glucosephosphate Dehydrogenase/metabolism , Spectrophotometry , Adolescent , Adult , Aged , Aged, 80 and over , Antimalarials/therapeutic use , Child , Child, Preschool , Female , Glucosephosphate Dehydrogenase Deficiency/drug therapy , Humans , Infant , Infant, Newborn , Malaria/epidemiology , Male , Middle Aged , Young Adult
5.
Lancet ; 394(10195): 332-343, 2019 07 27.
Article in English | MEDLINE | ID: mdl-31229233

ABSTRACT

BACKGROUND: Plasmodium vivax exacts a significant toll on health worldwide, yet few efforts to date have quantified the extent and temporal trends of its global distribution. Given the challenges associated with the proper diagnosis and treatment of P vivax, national malaria programmes-particularly those pursuing malaria elimination strategies-require up to date assessments of P vivax endemicity and disease impact. This study presents the first global maps of P vivax clinical burden from 2000 to 2017. METHODS: In this spatial and temporal modelling study, we adjusted routine malariometric surveillance data for known biases and used socioeconomic indicators to generate time series of the clinical burden of P vivax. These data informed Bayesian geospatial models, which produced fine-scale predictions of P vivax clinical incidence and infection prevalence over time. Within sub-Saharan Africa, where routine surveillance for P vivax is not standard practice, we combined predicted surfaces of Plasmodium falciparum with country-specific ratios of P vivax to P falciparum. These results were combined with surveillance-based outputs outside of Africa to generate global maps. FINDINGS: We present the first high-resolution maps of P vivax burden. These results are combined with those for P falciparum (published separately) to form the malaria estimates for the Global Burden of Disease 2017 study. The burden of P vivax malaria decreased by 41·6%, from 24·5 million cases (95% uncertainty interval 22·5-27·0) in 2000 to 14·3 million cases (13·7-15·0) in 2017. The Americas had a reduction of 56·8% (47·6-67·0) in total cases since 2000, while South-East Asia recorded declines of 50·5% (50·3-50·6) and the Western Pacific regions recorded declines of 51·3% (48·0-55·4). Europe achieved zero P vivax cases during the study period. Nonetheless, rates of decline have stalled in the past five years for many countries, with particular increases noted in regions affected by political and economic instability. INTERPRETATION: Our study highlights important spatial and temporal patterns in the clinical burden and prevalence of P vivax. Amid substantial progress worldwide, plateauing gains and areas of increased burden signal the potential for challenges that are greater than expected on the road to malaria elimination. These results support global monitoring systems and can inform the optimisation of diagnosis and treatment where P vivax has most impact. FUNDING: Bill & Melinda Gates Foundation and the Wellcome Trust.


Subject(s)
Endemic Diseases/statistics & numerical data , Malaria, Vivax/epidemiology , Africa/epidemiology , Americas/epidemiology , Asia, Southeastern/epidemiology , Bayes Theorem , Global Health , Humans , Oceania/epidemiology , Population Surveillance , Spatio-Temporal Analysis
6.
Lancet ; 394(10195): 322-331, 2019 07 27.
Article in English | MEDLINE | ID: mdl-31229234

ABSTRACT

BACKGROUND: Since 2000, the scale-up of malaria control interventions has substantially reduced morbidity and mortality caused by the disease globally, fuelling bold aims for disease elimination. In tandem with increased availability of geospatially resolved data, malaria control programmes increasingly use high-resolution maps to characterise spatially heterogeneous patterns of disease risk and thus efficiently target areas of high burden. METHODS: We updated and refined the Plasmodium falciparum parasite rate and clinical incidence models for sub-Saharan Africa, which rely on cross-sectional survey data for parasite rate and intervention coverage. For malaria endemic countries outside of sub-Saharan Africa, we produced estimates of parasite rate and incidence by applying an ecological downscaling approach to malaria incidence data acquired via routine surveillance. Mortality estimates were derived by linking incidence to systematically derived vital registration and verbal autopsy data. Informed by high-resolution covariate surfaces, we estimated P falciparum parasite rate, clinical incidence, and mortality at national, subnational, and 5 × 5 km pixel scales with corresponding uncertainty metrics. FINDINGS: We present the first global, high-resolution map of P falciparum malaria mortality and the first global prevalence and incidence maps since 2010. These results are combined with those for Plasmodium vivax (published separately) to form the malaria estimates for the Global Burden of Disease 2017 study. The P falciparum estimates span the period 2000-17, and illustrate the rapid decline in burden between 2005 and 2017, with incidence declining by 27·9% and mortality declining by 42·5%. Despite a growing population in endemic regions, P falciparum cases declined between 2005 and 2017, from 232·3 million (95% uncertainty interval 198·8-277·7) to 193·9 million (156·6-240·2) and deaths declined from 925 800 (596 900-1 341 100) to 618 700 (368 600-952 200). Despite the declines in burden, 90·1% of people within sub-Saharan Africa continue to reside in endemic areas, and this region accounted for 79·4% of cases and 87·6% of deaths in 2017. INTERPRETATION: High-resolution maps of P falciparum provide a contemporary resource for informing global policy and malaria control planning, programme implementation, and monitoring initiatives. Amid progress in reducing global malaria burden, areas where incidence trends have plateaued or increased in the past 5 years underscore the fragility of hard-won gains against malaria. Efforts towards elimination should be strengthened in such areas, and those where burden remained high throughout the study period. FUNDING: Bill & Melinda Gates Foundation.


Subject(s)
Malaria, Falciparum/epidemiology , Mortality/trends , Africa South of the Sahara/epidemiology , Cross-Sectional Studies , Global Health , Humans , Incidence , Malaria, Falciparum/mortality , Organizational Objectives , Prevalence , Spatio-Temporal Analysis
7.
Chembiochem ; 21(14): 2013-2018, 2020 07 16.
Article in English | MEDLINE | ID: mdl-32017335

ABSTRACT

The RNA-templated extension of oligoribonucleotides by nucleotides produces either a 3',5' or a 2',5'-phosphodiester. Nature controls the regioselectivity during RNA chain growth with polymerases, but enzyme-free versions of genetic copying have modest specificity. Thus far, enzymatic degradation of products, combined with chromatography or electrophoresis, has been the preferred mode of detecting 2',5'-diesters produced in enzyme-free reactions. This approach hinges on the substrate specificity of nucleases, and is not suitable for in situ monitoring. Here we report how 1 H NMR spectroscopy can be used to detect the extension of self-templating RNA hairpins and that this reveals the regioisomeric nature of the newly formed phosphodiesters. We studied several modes of activating nucleotides, including imidazolides, a pyridinium phosphate, an active ester, and in situ activation with carbodiimide and organocatalyst. Conversion into the desired extension product ranged from 20 to 90 %, depending on the leaving group. Integration of the resonances of H1' protons of riboses and H5 protons of pyrimidines gave regioselectivities ranging from 40:60 to 85:15 (3',5' to 2',5' diester), but no simple correlation between 3',5' selectivity and yield. Our results show how monitoring with a high-resolution technique sheds a new light on a process that may have played an important role during the emergence of life.


Subject(s)
Organophosphates/analysis , RNA/chemistry , Nucleic Acid Conformation , Nucleotides/chemistry , Proton Magnetic Resonance Spectroscopy , Stereoisomerism
8.
J Am Chem Soc ; 141(30): 12029-12043, 2019 07 31.
Article in English | MEDLINE | ID: mdl-31268701

ABSTRACT

Enzymes are Nature's polyfunctional catalysts tailor-made for specific biochemical synthetic transformations, which often proceed with almost perfect stereocontrol. From a synthetic point of view, artificial catalysts usually offer the advantage of much broader substrate scopes, but stereocontrol is often inferior to that possible with natural enzymes. A particularly difficult synthetic task in asymmetric catalysis is to overwrite a pronounced preference for the formation of an inherently favored diastereomer; this requires a high level of stereocontrol. In this Article, the development of a novel artificial polyfunctional catalyst type is described, in which an imidazolium-aryloxide betaine moiety cooperates with a Lewis acidic metal center (here Cu(II)) within a chiral catalyst framework. This strategy permits for the first time a general, highly enantioselective access to the otherwise rare diastereomer in the direct 1,4-addition of various 1,3-dicarbonyl substrates to ß-substituted nitroolefins. The unique stereocontrol by the polyfunctional catalyst system is also demonstrated with the highly stereoselective formation of a third contiguous stereocenter making use of a diastereoselective nitronate protonation employing α,ß-disubstituted nitroolefin substrates. Asymmetric 1,4-additions of ß-ketoesters to α,ß-disubstituted nitroolefins have never been reported before in literature. Combined mechanistic investigations including detailed spectroscopic and density functional theory (DFT) studies suggest that the aryloxide acts as a base to form a Cu(II)-bound enolate, whereas the nitroolefin is activated by H-bonds to the imidazolium unit and the phenolic OH generated during the proton transfer. Detailed kinetic analyses (RPKA, VTNA) suggest that (a) the catalyst is stable during the catalytic reaction, (b) not inhibited by product and (c) the rate-limiting step is most likely the C-C bond formation in agreement with the DFT calculations of the catalytic cycle. The robust catalyst is readily synthesized and recyclable and could also be applied to a cascade cyclization.

9.
PLoS Med ; 16(12): e1002992, 2019 12.
Article in English | MEDLINE | ID: mdl-31834890

ABSTRACT

BACKGROUND: To reduce the risk of drug-induced haemolysis, all patients should be tested for glucose-6-phosphate dehydrogenase (G6PD) deficiency (G6PDd) prior to prescribing primaquine (PQ)-based radical cure for the treatment of vivax malaria. This systematic review and individual patient meta-analysis assessed the utility of a qualitative lateral flow assay from Access Bio/CareStart (Somerset, NJ) (CareStart Screening test for G6PD deficiency) for the diagnosis of G6PDd compared to the gold standard spectrophotometry (International Prospective Register of Systematic Reviews [PROSPERO]: CRD42019110994). METHODS AND FINDINGS: Articles published on PubMed between 1 January 2011 and 27 September 2019 were screened. Articles reporting performance of the standard CSG from venous or capillary blood samples collected prospectively and considering spectrophotometry as gold standard (using kits from Trinity Biotech PLC, Wicklow, Ireland) were included. Authors of articles fulfilling the inclusion criteria were contacted to contribute anonymized individual data. Minimal data requested were sex of the participant, CSG result, spectrophotometry result in U/gHb, and haemoglobin (Hb) reading. The adjusted male median (AMM) was calculated per site and defined as 100% G6PD activity. G6PDd was defined as an enzyme activity of less than 30%. Pooled estimates for sensitivity and specificity, unconditional negative predictive value (NPV), positive likelihood ratio (LR+), and negative likelihood ratio (LR-) were calculated comparing CSG results to spectrophotometry using a random-effects bivariate model. Of 11 eligible published articles, individual data were available from 8 studies, 6 from Southeast Asia, 1 from Africa, and 1 from the Americas. A total of 5,815 individual participant data (IPD) were available, of which 5,777 results (99.3%) were considered for analysis, including data from 3,095 (53.6%) females. Overall, the CSG had a pooled sensitivity of 0.96 (95% CI 0.90-0.99) and a specificity of 0.95 (95% CI 0.92-0.96). When the prevalence of G6PDd was varied from 5% to 30%, the unconditional NPV was 0.99 (95% CI 0.94-1.00), with an LR+ and an LR- of 18.23 (95% CI 13.04-25.48) and 0.05 (95% CI 0.02-0.12), respectively. Performance was significantly better in males compared to females (p = 0.027) but did not differ significantly between samples collected from capillary or venous blood (p = 0.547). Limitations of the study include the lack of wide geographical representation of the included data and that the CSG results were generated under research conditions, and therefore may not reflect performance in routine settings. CONCLUSIONS: The CSG performed well at the 30% threshold. Its high NPV suggests that the test is suitable to guide PQ treatment, and the high LR+ and low LR- render the test suitable to confirm and exclude G6PDd. Further operational studies are needed to confirm the utility of the test in remote endemic settings.


Subject(s)
Diagnostic Tests, Routine , Glucosephosphate Dehydrogenase Deficiency/diagnosis , Glucosephosphate Dehydrogenase/genetics , Primaquine/therapeutic use , Diagnostic Tests, Routine/methods , Endemic Diseases , Female , Glucosephosphate Dehydrogenase Deficiency/drug therapy , Humans , Malaria/drug therapy , Malaria/epidemiology , Malaria, Vivax/epidemiology , Male , Point-of-Care Systems , Primaquine/adverse effects , Sensitivity and Specificity
11.
Malar J ; 18(1): 195, 2019 Jun 11.
Article in English | MEDLINE | ID: mdl-31186004

ABSTRACT

BACKGROUND: The disease burden of Plasmodium falciparum malaria illness is generally estimated using one of two distinct approaches: either by transforming P. falciparum infection prevalence estimates into incidence estimates using conversion formulae; or through adjustment of counts of recorded P. falciparum-positive fever cases from clinics. Whilst both ostensibly seek to evaluate P. falciparum disease burden, there is an implicit and problematic difference in the metric being estimated. The first enumerates only symptomatic malaria cases, while the second enumerates all febrile episodes coincident with a P. falciparum infection, regardless of the fever's underlying cause. METHODS: Here, a novel approach was used to triangulate community-based data sources capturing P. falciparum infection, fever, and care-seeking to estimate the fraction of P. falciparum-positive fevers amongst children under 5 years of age presenting at health facilities that are attributable to P. falciparum infection versus other non-malarial causes. A Bayesian hierarchical model was used to assign probabilities of malaria-attributable fever (MAF) and non-malarial febrile illness (NMFI) to children under five from a dataset of 41 surveys from 21 countries in sub-Saharan Africa conducted between 2006 and 2016. Using subsequent treatment-seeking outcomes, the proportion of MAF and NMFI amongst P. falciparum-positive febrile children presenting at public clinics was estimated. RESULTS: Across all surveyed malaria-positive febrile children who sought care at public clinics across 41 country-years in sub-Saharan Africa, P. falciparum infection was estimated to be the underlying cause of only 37.7% (31.1-45.4, 95% CrI) of P. falciparum-positive fevers, with significant geographical and temporal heterogeneity between surveys. CONCLUSIONS: These findings highlight the complex nature of the P. falciparum burden amongst children under 5 years of age and indicate that for many children presenting at health clinics, a positive P. falciparum diagnosis and a fever does not necessarily mean P. falciparum is the underlying cause of the child's symptoms, and thus other causes of illness should always be investigated, in addition to prescribing an effective anti-malarial medication. In addition to providing new large-scale estimates of malaria-attributable fever prevalence, the results presented here improve comparability between different methods for calculating P. falciparum disease burden, with significant implications for national and global estimation of malaria burden.


Subject(s)
Coinfection/epidemiology , Cost of Illness , Fever/epidemiology , Malaria, Falciparum/complications , Africa South of the Sahara/epidemiology , Child, Preschool , Epidemiologic Methods , Health Facilities , Humans , Infant , Infant, Newborn , Prevalence
12.
Malar J ; 17(1): 352, 2018 Oct 05.
Article in English | MEDLINE | ID: mdl-30290815

ABSTRACT

BACKGROUND: The Malaria Atlas Project (MAP) has worked to assemble and maintain a global open-access database of spatial malariometric data for over a decade. This data spans various formats and topics, including: geo-located surveys of malaria parasite rate; global administrative boundary shapefiles; and global and regional rasters representing the distribution of malaria and associated illnesses, blood disorders, and intervention coverage. MAP has recently released malariaAtlas, an R package providing a direct interface to MAP's routinely-updated malariometric databases and research outputs. METHODS AND RESULTS: The current paper reviews the functionality available in malariaAtlas and highlights its utility for spatial epidemiological analysis of malaria. malariaAtlas enables users to freely download, visualise and analyse global malariometric data within R. Currently available data types include: malaria parasite rate and vector occurrence point data; subnational administrative boundary shapefiles; and a large suite of rasters covering a diverse range of metrics related to malaria research. malariaAtlas is here used in two mock analyses to illustrate how this data may be incorporated into a standard R workflow for spatial analysis. CONCLUSIONS: malariaAtlas is the first open-access R-interface to malariometric data, providing a new and reproducible means of accessing such data within a freely available and commonly used statistical software environment. In this way, the malariaAtlas package aims to contribute to the environment of data-sharing within the malaria research community.


Subject(s)
Anopheles/physiology , Anopheles/parasitology , Databases, Factual , Malaria/epidemiology , Mosquito Vectors/physiology , Mosquito Vectors/parasitology , Software , Animal Distribution , Animals , Humans , Incidence , Malaria/parasitology , Prevalence
13.
Nicotine Tob Res ; 20(9): 1038-1046, 2018 08 14.
Article in English | MEDLINE | ID: mdl-29059355

ABSTRACT

Background: Despite the centrality of addiction in academic accounts of smoking, there is little research on smokers' beliefs about addiction to smoking, and the role of nicotine in tobacco dependence. Smokers' perspectives on nicotine's role in addiction are important given the increasing prevalence of nontobacco nicotine products such as e-cigarettes. We conducted a systematic review of studies investigating smokers' understandings and lay beliefs about addiction to smoking and nicotine. Method: We searched PubMed, Embase, CINAHL, and PsycINFO for studies investigating lay beliefs about addiction to smoking. Twenty-two quantitative and 24 qualitative studies met inclusion criteria. Critical interpretive synthesis was used to analyze the results. Results: Very few studies asked about addiction to nicotine. Quantitative studies that asked about addiction to smoking showed that most smokers believe that cigarettes are an addictive product, and that they are addicted to smoking. Across qualitative studies, nicotine was not often mentioned by participants. Addiction to smoking was most often characterized as a feeling of "need" for cigarettes resulting from an interplay between physical, mental, and social processes. Overall, we found that understandings of smoking were more consistent with the biopsychosocial model of addiction than with more recent models that emphasize the biological aspects of addiction. Conclusion: Researchers should not treat perceptions of addiction to smoking interchangeably with perceptions of addiction to nicotine. More research on lay beliefs about nicotine is required, particularly considering the increasing use of e-cigarettes and their potential for long-term nicotine maintenance for harm reduction. Implications: Quantitative studies show that most smokers believe that smoking is addictive and that they are addicted. A feeling of "need" for cigarettes was central to qualitative accounts of addiction, but nicotine was not often discussed. Overall, smokers' understandings of addiction reflect a biopsychosocial model rather than a neurobiological one. Given the growing market for e-cigarettes and therapeutic nicotine, more research is required on lay beliefs about nicotine and addiction.


Subject(s)
Comprehension , Qualitative Research , Smokers/psychology , Smoking Cessation/psychology , Tobacco Smoking/psychology , Tobacco Use Disorder/psychology , Adolescent , Adult , Behavior, Addictive/psychology , Electronic Nicotine Delivery Systems/methods , Female , Humans , Male , Nicotine/administration & dosage , Nicotine/adverse effects , Smoking Cessation/methods , Smoking Prevention/methods , Nicotiana/adverse effects , Tobacco Smoking/therapy , Tobacco Use Cessation Devices , Tobacco Use Disorder/diagnosis , Tobacco Use Disorder/therapy
14.
BMC Oral Health ; 18(1): 120, 2018 07 04.
Article in English | MEDLINE | ID: mdl-29973186

ABSTRACT

BACKGROUND: Incisor loss constitutes a strong aesthetic and psychologic traumatism for the patient and it remains a challenging situation for the dental practitioner because of the necessity to rapidly replace the lacking tooth. Various therapeutic procedures have been proposed to replace the incisor concerned, for example by using a removable partial denture. However, the manufacturing of such a denture with classical procedures is often subject to processing errors and inaccuracies. The computer-aided design and computer-aided manufacturing (CAD-CAM) technology could represent a good alternative, but it is currently difficult because of the lack of dental softwares able to design easily immediate removable partial dentures. CASE PRESENTATION: A 30-year- patient complained about pain caused by a horizontally and vertically mobile maxillary right central incisor. After all options were presented, extraction of the traumatized incisor was decided due to its very poor prognosis, and the patient selected the realization of a removable denture for economic reasons. The present paper proposes an innovative procedure for immediate removable denture, based on the use of an intraoral scanner, CAD with two different softwares used sequentially, and CAM with a 5-axis machine. CONCLUSIONS: We show in this report that associating an intraoral scanner and CAD-CAM technology can be extended to immediate dentures manufacturing, which could be a valuable procedure for dental practitioners and laboratories, and also for patients.


Subject(s)
Computer-Aided Design , Denture Design/methods , Denture, Partial, Removable , Adult , Humans , Imaging, Three-Dimensional/instrumentation , Imaging, Three-Dimensional/methods , Incisor/injuries , Male , Tooth Avulsion/surgery , Tooth Extraction
15.
Aust N Z J Psychiatry ; 51(11): 1106-1120, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28859486

ABSTRACT

OBJECTIVE: To review the quality of current smoking cessation guidelines that include recommendations for people with severe mental illness. METHODS: A systematic search of scientific databases, central government health authority websites, psychiatry peak bodies, guideline clearing houses and Google was undertaken for relevant smoking cessation guidelines. Three reviewers independently assessed guideline quality using the AGREE II (Appraisal of Guidelines for REsearch and Evaluation II) instrument. Two reviewers extracted recommendations specific to smokers with severe mental illness. RESULTS: Thirteen guidelines met the inclusion criteria. Seven guidelines scored ⩾60% in at least four domains. Median scores for 'Editorial independence', 'Rigour of development', 'Stakeholder Involvement' and 'Applicability' were less than 60%. The highest median scores were for 'Scope and purpose' (87%, 69-96%) and 'Clarity of presentation' (87%, 56-98%). 'Editorial independence' (33.3%, 0-86%) and 'Rigour of development' (54%, 11-92%) had the lowest median domain scores. The guidelines varied greatly in their recommendations but the majority recommended nicotine replacement therapy, bupropion or varenicline as first-line pharmacotherapy, along with behavioural support. CONCLUSION: Many guidelines did not adequately report their methods or the competing interests of the authors. Future guidelines development may benefit from more specifically addressing AGREE II criteria and the needs of smokers with severe mental illness.


Subject(s)
Mental Disorders , Practice Guidelines as Topic/standards , Smoking Cessation/methods , Smoking/therapy , Comorbidity , Humans , Mental Disorders/epidemiology , Smoking/drug therapy , Smoking/epidemiology
17.
Echo Res Pract ; 11(1): 3, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38321564

ABSTRACT

BACKGROUND: Ultrasound enhancing agents (UEAs) are an invaluable adjunct to stress and transthoracic echocardiography (STE) to improve left ventricular visualization. Despite multiple single center studies evaluating UEA use, investigation into the rates, sources of variation, and outcomes of UEA use on a national level in the United States (US) has been limited by lack of validation of UEA codes for claims analyses. METHODS: We conducted a retrospective cross-sectional study, 2019-2022, using linked multicenter electronic medical record (EMR) data from > 30 health systems linked to all-payor claims data representing > 90% of the US population. Individuals receiving STE in both EMR and claims data on the same day during the study window were included. UEA receipt as identified by presence of a Current Procedural Terminology (CPT) or National Drug Code (NDC) for UEA use within 1-day of the index STE event. We evaluated the performance of claims to identify UEA use, using EMR data as the gold standard, stratified by inpatient and outpatient status. RESULTS: Amongst 54,525 individuals receiving STE in both EMR and claims data, 12,853 (23.6%) had a UEA claim in EMR, 10,461 (19.2%) had a UEA claim in claims, and 9140 (16.8%) had a UEA claim in both within the 1-day window. The sensitivity, specificity, accuracy, positive, and negative predictive values for UEA claims were 71.1%, 96.8%, 90.8%, 87.4%. and 91.6% respectively. However, amongst inpatients, the sensitivity of UEA claims was substantially lower (6.8%) compared to outpatients (79.7%). CONCLUSIONS: While the overall accuracy of claims to identify UEA use was high, there was substantial under-capture of UEA use by claims amongst inpatients. These results call into question published rates of UEA use amongst inpatients in studies using administrative claims, and highlight ongoing need to improve inpatient coding for UEA use.

18.
Nutrients ; 15(17)2023 Aug 30.
Article in English | MEDLINE | ID: mdl-37686821

ABSTRACT

Due to multifactorial reasons, such as decreased thirst and decreased total body water, elderly patients are vulnerable to dehydration. The study aims to investigate whether moderate dehydration or hyperhydration affects the blood proteome. Blood samples, medication, and bioelectrical impedance analysis (BIA) details were collected from 131 geriatric patients (77 women and 54 men aged 81.1 ± 7.2 years). Based on an evaluation by Bioelectrical Impedance Vector Analyses (BIVAs) of this cohort, for each hydration status (dehydrated, hyperhydrated, and control), five appropriate blood plasma samples for both males and females were analyzed by liquid chromatography-mass spectrometry (LC-MS). Overall, 262 proteins for female patients and 293 proteins for male patients could be quantified. A total of 38 proteins had significantly different abundance, showing that hydration status does indeed affect the plasma proteome. Protein enrichment analysis of the affected proteins revealed "Wound Healing" and "Keratinization" as the two main biological processes being dysregulated. Proteins involved in clot formation are especially affected by hydration status.


Subject(s)
Dehydration , Proteome , Aged , Humans , Female , Male , Blood Coagulation , Plasma , Wound Healing
19.
JPEN J Parenter Enteral Nutr ; 46(7): 1614-1622, 2022 09.
Article in English | MEDLINE | ID: mdl-35726729

ABSTRACT

BACKGROUND: This study investigated the prevalence, characteristics, and management of patients with chronic intestinal failure (CIF) in the United States in 2012-2020, based on parenteral support (PS) prescription claims and healthcare utilization. METHODS: Patients with CIF were identified from the Integrated DataVerse® claims database if they had at least two PS prescriptions within 6 months and a relevant diagnosis. Analysis included prevalence and characteristics of patients with CIF, their travel distance to receive PS prescriptions, and the distribution of PS providers and their prescribing history. RESULTS: Up to 24,048 patients with CIF were identified, equivalent to 75 patients per million. CIF affected people of all ages, being more prevalent in women than in men. Many providers signed PS orders for small patient groups over short time periods, whereas few providers signed PS orders for large patient groups long term, indicating a lack of centralization. The distribution of PS providers suggested a disparity in healthcare coverage in rural vs urban areas, leading to patients traveling considerable distances to receive PS prescriptions. This may be exacerbated by a decline of providers with expertise in CIF and nutrition. CONCLUSIONS: Healthcare disparities for patients with CIF have likely been obscured by the lack of CIF-specific diagnostic and procedure codes, obliging providers to code for their patients under other codes. Effective policy changes, including centralized care, revision of reimbursement models, and expansion of nutrition-focused education in addition to the newly introduced International Classification of Diseases codes, are needed to provide the best care for patients.


Subject(s)
Intestinal Diseases , Intestinal Failure , Chronic Disease , Female , Humans , Intestinal Diseases/epidemiology , Intestinal Diseases/therapy , Male , Parenteral Nutrition , Prevalence , United States/epidemiology
20.
Pathogens ; 11(9)2022 Sep 14.
Article in English | MEDLINE | ID: mdl-36145477

ABSTRACT

Low glucose-6-phosphate dehydrogenase enzyme (G6PD) activity is a key determinant of drug-induced haemolysis. More than 230 clinically relevant genetic variants have been described. We investigated the variation in G6PD activity within and between different genetic variants. In this systematic review, individual patient data from studies reporting G6PD activity measured by spectrophotometry and corresponding the G6PD genotype were pooled (PROSPERO: CRD42020207448). G6PD activity was converted into percent normal activity applying study-specific definitions of 100%. In total, 4320 individuals from 17 studies across 10 countries were included, where 1738 (40.2%) had one of the 24 confirmed G6PD mutations, and 61 observations (3.5%) were identified as outliers. The median activity of the hemi-/homozygotes with A-(c.202G>A/c.376A>G) was 29.0% (range: 1.7% to 76.6%), 10.2% (range: 0.0% to 32.5%) for Mahidol, 16.9% (range 3.3% to 21.3%) for Mediterranean, 9.0% (range: 2.9% to 23.2%) for Vanua Lava, and 7.5% (range: 0.0% to 18.3%) for Viangchan. The median activity in heterozygotes was 72.1% (range: 16.4% to 127.1%) for A-(c.202G>A/c.376A>G), 54.5% (range: 0.0% to 112.8%) for Mahidol, 37.9% (range: 20.7% to 80.5%) for Mediterranean, 53.8% (range: 10.9% to 82.5%) for Vanua Lava, and 52.3% (range: 4.8% to 78.6%) for Viangchan. A total of 99.5% of hemi/homozygotes with the Mahidol mutation and 100% of those with the Mediterranean, Vanua Lava, and Viangchan mutations had <30% activity. For A-(c.202G>A/c.376A>G), 55% of hemi/homozygotes had <30% activity. The G6PD activity for each variant spanned the current classification thresholds used to define clinically relevant categories of enzymatic deficiency.

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