RESUMEN
Human clinical trials suggest that inhibition of enzymes in the DNA base excision repair (BER) pathway, such as PARP1 and APE1, can be useful in anticancer strategies when combined with certain DNA-damaging agents or tumor-specific genetic deficiencies. There is also evidence suggesting that inhibition of the BER enzyme 8-oxoguanine DNA glycosylase-1 (OGG1), which initiates repair of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG) and 2,6-diamino-4-hydroxy-5-formamidopyrimidine (Fapy-dG), could be useful in treating certain cancers. Specifically, in acute myeloid leukemia (AML), both the RUNX1-RUNX1T1 fusion and the CBFB-MYH11 subtypes have lower levels of OGG1 expression, which correlate with increased therapeutic-induced cell cytotoxicity and good prognosis for improved, relapse-free survival compared with other AML patients. Here we present data demonstrating that AML cell lines deficient in OGG1 have enhanced sensitivity to cytarabine (cytosine arabinoside [Ara-C]) relative to OGG1-proficient cells. This enhanced cytotoxicity correlated with endogenous oxidatively-induced DNA damage and Ara-C-induced DNA strand breaks, with a large proportion of these breaks occurring at common fragile sites. This lethality was highly specific for Ara-C treatment of AML cells deficient in OGG1, with no other replication stress-inducing agents showing a correlation between cell killing and low OGG1 levels. The mechanism for this preferential toxicity was addressed using in vitro replication assays in which DNA polymerase δ was shown to insert Ara-C opposite 8-oxo-dG, resulting in termination of DNA synthesis. Overall, these data suggest that incorporation of Ara-C opposite unrepaired 8-oxo-dG may be the fundamental mechanism conferring selective toxicity and therapeutic effectiveness in OGG1-deficient AML cells.
Asunto(s)
Antimetabolitos Antineoplásicos/farmacología , Citarabina/farmacología , ADN Glicosilasas/genética , Leucemia Mieloide Aguda/patología , 8-Hidroxi-2'-Desoxicoguanosina/genética , Línea Celular Tumoral , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Reparación del ADN , Humanos , Leucemia Mieloide Aguda/enzimología , ARN Mensajero/genéticaRESUMEN
ABSTRACT: Traditional clinical experiences offer opportunities for nursing students to practice critical thinking. However, there are many limitations to planning these clinical experiences. The purpose of this educational activity is to incorporate post-conference simulation with traditional clinical to allow undergraduate nursing students expanded opportunities for enhancing critical thinking. The faculty created high-acuity simulation scenarios, which included a child experiencing respiratory, hematologic, neurological, or cardiovascular complications. After participating in the activity, students completed evaluation and reported increased confidence and preparedness to identify, think critically, and intervene in high-acuity situations.
RESUMEN
Dietary exposure to aflatoxins is a significant risk factor in the development of hepatocellular carcinomas. Following bioactivation by microsomal P450s, the reaction of aflatoxin B1 (AFB1) with guanine (Gua) in DNA leads to the formation of stable, imidazole ring-opened 8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxyaflatoxin B1 (AFB1-FapyGua) adducts. In contrast to most base modifications that result in destabilization of the DNA duplex, the AFB1-FapyGua adduct increases the thermal stability of DNA via 5'-interface intercalation and base-stacking interactions. Although it was anticipated that this stabilization might make these lesions difficult to repair relative to helix distorting modifications, prior studies have shown that both the nucleotide and base excision repair pathways participate in the removal of the AFB1-FapyGua adduct. Specifically for base excision repair, we previously showed that the DNA glycosylase NEIL1 excises AFB1-FapyGua and catalyzes strand scission in both synthetic oligodeoxynucleotides and liver DNA of exposed mice. Since it is anticipated that error-prone replication bypass of unrepaired AFB1-FapyGua adducts contributes to cellular transformation and carcinogenesis, the structural and thermodynamic parameters that modulate the efficiencies of these repair pathways are of considerable interest. We hypothesized that the DNA sequence context in which the AFB1-FapyGua adduct is formed might modulate duplex stability and consequently alter the efficiencies of NEIL1-initiated repair. To address this hypothesis, site-specific AFB1-FapyGua adducts were synthesized in three sequence contexts, with the 5' neighbor nucleotide being varied. DNA structural stability analyses were conducted using UV absorbance- and NMR-based melting experiments. These data revealed differentials in thermal stabilities associated with the 5'-neighbor base pair. Single turnover kinetic analyses using the NEIL1 glycosylase demonstrated corresponding sequence-dependent differences in the repair of this adduct, such that there was an inverse correlation between the stabilization of the duplex and the efficiency of NEIL1-mediated catalysis.
Asunto(s)
Aflatoxina B1/metabolismo , Aductos de ADN/metabolismo , ADN Glicosilasas/metabolismo , ADN/metabolismo , Guanina/metabolismo , Pirimidinas/metabolismo , Aflatoxina B1/química , Secuencia de Bases , Biocatálisis , ADN/química , Aductos de ADN/química , ADN Glicosilasas/química , Guanina/química , Humanos , Estructura Molecular , Pirimidinas/químicaRESUMEN
Global distribution of hepatocellular carcinomas (HCCs) is dominated by its incidence in developing countries, accounting for >700,000 estimated deaths per year, with dietary exposures to aflatoxin (AFB1) and subsequent DNA adduct formation being a significant driver. Genetic variants that increase individual susceptibility to AFB1-induced HCCs are poorly understood. Herein, it is shown that the DNA base excision repair (BER) enzyme, DNA glycosylase NEIL1, efficiently recognizes and excises the highly mutagenic imidazole ring-opened AFB1-deoxyguanosine adduct (AFB1-Fapy-dG). Consistent with this in vitro result, newborn mice injected with AFB1 show significant increases in the levels of AFB1-Fapy-dG in Neil1-/- vs. wild-type liver DNA. Further, Neil1-/- mice are highly susceptible to AFB1-induced HCCs relative to WT controls, with both the frequency and average size of hepatocellular carcinomas being elevated in Neil1-/- The magnitude of this effect in Neil1-/- mice is greater than that previously measured in Xeroderma pigmentosum complementation group A (XPA) mice that are deficient in nucleotide excision repair (NER). Given that several human polymorphic variants of NEIL1 are catalytically inactive for their DNA glycosylase activity, these deficiencies may increase susceptibility to AFB1-associated HCCs.
Asunto(s)
Aflatoxinas/toxicidad , Carcinoma Hepatocelular/prevención & control , Aductos de ADN/efectos de los fármacos , ADN Glicosilasas/fisiología , Neoplasias Hepáticas Experimentales/prevención & control , Sustancias Protectoras/farmacología , Animales , Carcinoma Hepatocelular/inducido químicamente , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Femenino , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/metabolismo , Neoplasias Hepáticas Experimentales/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Venenos/toxicidadRESUMEN
BACKGROUND: Macrolide antibiotics (macrolides) are among the most commonly prescribed antibiotics worldwide and are used for a wide range of infections. However, macrolides also expose people to the risk of adverse events. The current understanding of adverse events is mostly derived from observational studies, which are subject to bias because it is hard to distinguish events caused by antibiotics from events caused by the diseases being treated. Because adverse events are treatment-specific, rather than disease-specific, it is possible to increase the number of adverse events available for analysis by combining randomised controlled trials (RCTs) of the same treatment across different diseases. OBJECTIVES: To quantify the incidences of reported adverse events in people taking macrolide antibiotics compared to placebo for any indication. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), which includes the Cochrane Acute Respiratory Infections Group Specialised Register (2018, Issue 4); MEDLINE (Ovid, from 1946 to 8 May 2018); Embase (from 2010 to 8 May 2018); CINAHL (from 1981 to 8 May 2018); LILACS (from 1982 to 8 May 2018); and Web of Science (from 1955 to 8 May 2018). We searched clinical trial registries for current and completed trials (9 May 2018) and checked the reference lists of included studies and of previous Cochrane Reviews on macrolides. SELECTION CRITERIA: We included RCTs that compared a macrolide antibiotic to placebo for any indication. We included trials using any of the four most commonly used macrolide antibiotics: azithromycin, clarithromycin, erythromycin, or roxithromycin. Macrolides could be administered by any route. Concomitant medications were permitted provided they were equally available to both treatment and comparison groups. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted and collected data. We assessed the risk of bias of all included studies and the quality of evidence for each outcome of interest. We analysed specific adverse events, deaths, and subsequent carriage of macrolide-resistant bacteria separately. The study participant was the unit of analysis for each adverse event. Any specific adverse events that occurred in 5% or more of any group were reported. We undertook a meta-analysis when three or more included studies reported a specific adverse event. MAIN RESULTS: We included 183 studies with a total of 252,886 participants (range 40 to 190,238). The indications for macrolide antibiotics varied greatly, with most studies using macrolides for the treatment or prevention of either acute respiratory tract infections, cardiovascular diseases, chronic respiratory diseases, gastrointestinal conditions, or urogynaecological problems. Most trials were conducted in secondary care settings. Azithromycin and erythromycin were more commonly studied than clarithromycin and roxithromycin.Most studies (89%) reported some adverse events or at least stated that no adverse events were observed.Gastrointestinal adverse events were the most commonly reported type of adverse event. Compared to placebo, macrolides caused more diarrhoea (odds ratio (OR) 1.70, 95% confidence interval (CI) 1.34 to 2.16; low-quality evidence); more abdominal pain (OR 1.66, 95% CI 1.22 to 2.26; low-quality evidence); and more nausea (OR 1.61, 95% CI 1.37 to 1.90; moderate-quality evidence). Vomiting (OR 1.27, 95% CI 1.04 to 1.56; moderate-quality evidence) and gastrointestinal disorders not otherwise specified (NOS) (OR 2.16, 95% CI 1.56 to 3.00; moderate-quality evidence) were also reported more often in participants taking macrolides compared to placebo.The number of additional people (absolute difference in risk) who experienced adverse events from macrolides was: gastrointestinal disorders NOS 85/1000; diarrhoea 72/1000; abdominal pain 62/1000; nausea 47/1000; and vomiting 23/1000.The number needed to treat for an additional harmful outcome (NNTH) ranged from 12 (95% CI 8 to 23) for gastrointestinal disorders NOS to 17 (9 to 47) for abdominal pain; 19 (12 to 33) for diarrhoea; 19 (13 to 30) for nausea; and 45 (22 to 295) for vomiting.There was no clear consistent difference in gastrointestinal adverse events between different types of macrolides or route of administration.Taste disturbances were reported more often by participants taking macrolide antibiotics, although there were wide confidence intervals and moderate heterogeneity (OR 4.95, 95% CI 1.64 to 14.93; I² = 46%; low-quality evidence).Compared with participants taking placebo, those taking macrolides experienced hearing loss more often, however only four studies reported this outcome (OR 1.30, 95% CI 1.00 to 1.70; I² = 0%; low-quality evidence).We did not find any evidence that macrolides caused more cardiac disorders (OR 0.87, 95% CI 0.54 to 1.40; very low-quality evidence); hepatobiliary disorders (OR 1.04, 95% CI 0.27 to 4.09; very low-quality evidence); or changes in liver enzymes (OR 1.56, 95% CI 0.73 to 3.37; very low-quality evidence) compared to placebo.We did not find any evidence that appetite loss, dizziness, headache, respiratory symptoms, blood infections, skin and soft tissue infections, itching, or rashes were reported more often by participants treated with macrolides compared to placebo.Macrolides caused less cough (OR 0.57, 95% CI 0.40 to 0.80; moderate-quality evidence) and fewer respiratory tract infections (OR 0.70, 95% CI 0.62 to 0.80; moderate-quality evidence) compared to placebo, probably because these are not adverse events, but rather characteristics of the indications for the antibiotics. Less fever (OR 0.73, 95% 0.54 to 1.00; moderate-quality evidence) was also reported by participants taking macrolides compared to placebo, although these findings were non-significant.There was no increase in mortality in participants taking macrolides compared with placebo (OR 0.96, 95% 0.87 to 1.06; I² = 11%; low-quality evidence).Only 24 studies (13%) provided useful data on macrolide-resistant bacteria. Macrolide-resistant bacteria were more commonly identified among participants immediately after exposure to the antibiotic. However, differences in resistance thereafter were inconsistent.Pharmaceutical companies supplied the trial medication or funding, or both, for 91 trials. AUTHORS' CONCLUSIONS: The macrolides as a group clearly increased rates of gastrointestinal adverse events. Most trials made at least some statement about adverse events, such as "none were observed". However, few trials clearly listed adverse events as outcomes, reported on the methods used for eliciting adverse events, or even detailed the numbers of people who experienced adverse events in both the intervention and placebo group. This was especially true for the adverse event of bacterial resistance.
Asunto(s)
Antibacterianos/efectos adversos , Macrólidos/efectos adversos , Dolor Abdominal/inducido químicamente , Enfermedades de los Conductos Biliares/inducido químicamente , Diarrea/inducido químicamente , Pérdida Auditiva/inducido químicamente , Cardiopatías/inducido químicamente , Humanos , Macrólidos/uso terapéutico , Náusea/inducido químicamente , Números Necesarios a Tratar , Placebos , Ensayos Clínicos Controlados Aleatorios como Asunto , Trastornos del Gusto/inducido químicamente , Vómitos/inducido químicamenteRESUMEN
Routine dietary consumption of foods that contain aflatoxins is the second leading cause of environmental carcinogenesis worldwide. Aflatoxin-driven mutagenesis is initiated through metabolic activation of aflatoxin B1 (AFB1) to its epoxide form that reacts with N7 guanine in DNA. The resulting AFB1-N7-dG adduct undergoes either spontaneous depurination or imidazole-ring opening yielding formamidopyrimidine AFB1 (AFB1-Fapy-dG). Because this latter adduct is known to persist in human tissues and contributes to the high frequency G-to-T mutation signature associated with many hepatocellular carcinomas, we sought to establish the identity of the polymerase(s) involved in processing this lesion. Although our previous biochemical analyses demonstrated the ability of polymerase ζ (pol ζ) to incorporate an A opposite AFB1-Fapy-dG and extend from this mismatch, biological evidence supporting a unique role for this polymerase in cellular tolerance following aflatoxin exposure has not been established. Following challenge with AFB1, survival of mouse cells deficient in pol ζ (Rev3L-/-) was significantly reduced relative to Rev3L+/- cells or Rev3L-/- cells complemented through expression of the wild-type human REV3L. Furthermore, cell-cycle progression of Rev3L-/- mouse embryo fibroblasts was arrested in late S/G2 following AFB1 exposure. These Rev3L-/- cells showed an increase in replication-dependent formation of γ-H2AX foci, micronuclei, and chromosomal aberrations (chromatid breaks and radials) relative to Rev3L+/- cells. These data suggest that pol ζ is essential for processing AFB1-induced DNA adducts and that, in its absence, cells do not have an efficient backup polymerase or a repair/tolerance mechanism facilitating survival.
Asunto(s)
Carcinoma Hepatocelular/genética , Proteínas de Unión al ADN/genética , ADN Polimerasa Dirigida por ADN/genética , Neoplasias Hepáticas/genética , Aflatoxina B1/análogos & derivados , Aflatoxina B1/genética , Aflatoxina B1/toxicidad , Aflatoxinas/toxicidad , Animales , Carcinoma Hepatocelular/inducido químicamente , Carcinoma Hepatocelular/patología , Supervivencia Celular/efectos de los fármacos , Aberraciones Cromosómicas/efectos de los fármacos , Citidina/análogos & derivados , Citidina/genética , Citidina/toxicidad , Aductos de ADN/efectos de los fármacos , Aductos de ADN/genética , Daño del ADN/efectos de los fármacos , Reparación del ADN/genética , ADN Polimerasa Dirigida por ADN/química , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Neoplasias Hepáticas/inducido químicamente , Neoplasias Hepáticas/patología , Ratones , Mutagénesis/efectos de los fármacos , Mutagénesis/genética , MutaciónRESUMEN
BACKGROUND: Effectiveness of interventions in pragmatic trials may not translate directly into population impact, because of limited uptake by clinicians and/or the public. Uptake of an intervention is influenced by a number of factors. METHODS: We propose a method for calculating population impact of clinical interventions that accounts for the intervention uptake. We suggest that population impact may be estimated by multiplying the two key components: (1) the effectiveness of the intervention in pragmatic trials (trial effect); and, (2) its uptake in clinical practice. We argue that participation rates in trials may be a valid proxy for uptake in clinical practice and, in combination with trial effectiveness estimates, be used to rank interventions by their likely population impact. We illustrate the method using the example of four interventions to decrease antibiotic prescription for acute respiratory infections in primary care: delayed prescribing, procalcitonin test, C-Reactive Protein, shared decision making. RESULTS: In order to estimate uptake of interventions from trial data we need detailed reporting on the recruitment processes used for clinician participation in the trials. In the antibiotic prescribing example, between 75 and 91% of the population would still be prescribed or consume antibiotics because effective interventions were not taken up. Of the four interventions considered, we found that delayed prescribing would have the highest population impact and shared decision making the lowest. CONCLUSION: Estimates of uptake and population impact of an intervention may be possible from pragmatic RCTs, provided the recruitment processes for these trials are adequately reported (which currently few of them are). Further validation of this method using empirical data on intervention uptake in the real world would support use of this method to decide on public funding of interventions.
Asunto(s)
Evaluación de Resultado en la Atención de Salud/métodos , Participación del Paciente , Pautas de la Práctica en Medicina , Ensayos Clínicos Pragmáticos como Asunto/métodos , Enfermedad Aguda , Antibacterianos/uso terapéutico , Proteína C-Reactiva/análisis , Calcitonina/análisis , Comunicación , Toma de Decisiones , Humanos , Atención Primaria de Salud/métodos , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones del Sistema Respiratorio/patología , Factores de TiempoRESUMEN
OBJECTIVE: To compare the current rate of antibiotic prescribing for acute respiratory infections (ARIs) in Australian general practice with the recommendations in the most widely consulted therapeutic guidelines in Australia (Therapeutic Guidelines). DESIGN AND SETTING: Comparison of general practice activity data for April 2010 - March 2015 (derived from Bettering the Evaluation and Care of Health [BEACH] study) with estimated rates of prescribing recommended by Therapeutic Guidelines. MAIN OUTCOME MEASURES: Antibiotic prescribing rates and estimated guideline-recommended rates per 100 encounters and per full-time equivalent (FTE) GP per year for eight ARIs; number of prescriptions nationally per year. RESULTS: An estimated mean 5.97 million (95% CI, 5.69-6.24 million) ARI cases per year were managed in Australian general practice with at least one antibiotic, equivalent to an estimated 230 cases per FTE GP/year (95% CI, 219-240 cases/FTE/year). Antibiotics are not recommended by the guidelines for acute bronchitis/bronchiolitis (current prescribing rate, 85%) or influenza (11%); they are always recommended for community-acquired pneumonia (current prescribing rate, 72%) and pertussis (71%); and they are recommended for 0.5-8% of cases of acute rhinosinusitis (current prescribing rate, 41%), 20-31% of cases of acute otitis media (89%), and 19-40% cases of acute pharyngitis or tonsillitis (94%). Had GPs adhered to the guidelines, they would have prescribed antibiotics for 0.65-1.36 million ARIs per year nationally, or at 11-23% of the current prescribing rate. Antibiotics were prescribed more frequently than recommended for acute rhinosinusitis, acute bronchitis/bronchiolitis, acute otitis media, and acute pharyngitis/tonsillitis. CONCLUSIONS: Antibiotics are prescribed for ARIs at rates 4-9 times as high as those recommended by Therapeutic Guidelines. Our data provide the basis for setting absolute targets for reducing antibiotic prescribing in Australian general practice.
Asunto(s)
Antibacterianos/uso terapéutico , Medicina General/estadística & datos numéricos , Prescripción Inadecuada/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Enfermedad Aguda , Australia , Adhesión a Directriz , Humanos , Guías de Práctica Clínica como Asunto , Atención Primaria de Salud , Derivación y Consulta , Infecciones del Sistema Respiratorio/clasificaciónRESUMEN
BACKGROUND: Antibiotic resistance is a worldwide health threat. Interventions that reduce antibiotic prescribing by clinicians are expected to reduce antibiotic resistance. Disparate interventions to change antibiotic prescribing behaviour for acute respiratory infections (ARIs) have been trialled and meta-analysed, but not yet synthesised in an overview. This overview synthesises evidence from systematic reviews, rather than individual trials. OBJECTIVES: To systematically review the existing evidence from systematic reviews on the effects of interventions aimed at influencing clinician antibiotic prescribing behaviour for ARIs in primary care. METHODS: We searched the Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects (DARE), MEDLINE, Embase, CINAHL, PsycINFO, and Science Citation Index to June 2016. We also searched the reference lists of all included reviews. We ran a pre-publication search in May 2017 and placed additional studies in 'awaiting classification'.We included both Cochrane and non-Cochrane reviews of randomised controlled trials evaluating the effect of any clinician-focussed intervention on antibiotic prescribing behaviour in primary care. Two overview authors independently extracted data and assessed the methodological quality of included reviews using the ROBIS tool, with disagreements reached by consensus or by discussion with a third overview author. We used the GRADE system to assess the quality of evidence in included reviews. The results are presented as a narrative overview. MAIN RESULTS: We included eight reviews in this overview: five Cochrane Reviews (33 included trials) and three non-Cochrane reviews (11 included trials). Three reviews (all Cochrane Reviews) scored low risk across all the ROBIS domains in Phase 2 and low risk of bias overall. The remaining five reviews scored high risk on Domain 4 of Phase 2 because the 'Risk of bias' assessment had not been specifically considered and discussed in the review Results and Conclusions. The trials included in the reviews varied in both size and risk of bias. Interventions were compared to usual care.Moderate-quality evidence indicated that C-reactive protein (CRP) point-of-care testing (risk ratio (RR) 0.78, 95% confidence interval (CI) 0.66 to 0.92, 3284 participants, 6 trials), shared decision making (odds ratio (OR) 0.44, 95% CI 0.26 to 0.75, 3274 participants, 3 trials; RR 0.64, 95% CI 0.49 to 0.84, 4623 participants, 2 trials; risk difference -18.44, 95% CI -27.24 to -9.65, 481,807 participants, 4 trials), and procalcitonin-guided management (adjusted OR 0.10, 95% CI 0.07 to 0.14, 1008 participants, 2 trials) probably reduce antibiotic prescribing in general practice. We found moderate-quality evidence that procalcitonin-guided management probably reduces antibiotic prescribing in emergency departments (adjusted OR 0.34, 95% CI 0.28 to 0.43, 2605 participants, 7 trials). The overall effect of these interventions was small (few achieving greater than 50% reduction in antibiotic prescribing, most about a quarter or less), but likely to be clinically important.Compared to usual care, shared decision making probably makes little or no difference to reconsultation for the same illness (RR 0.87, 95% CI 0.74 to 1.03, 1860 participants, 4 trials, moderate-quality evidence), and may make little or no difference to patient satisfaction (RR 0.86, 95% CI 0.57 to 1.30, 1110 participants, 2 trials, low-quality evidence). Similarly, CRP testing probably has little or no effect on patient satisfaction (RR 0.79, 95% CI 0.57 to 1.08, 689 participants, 2 trials, moderate-quality evidence) or reconsultation (RR 1.08, 95% CI 0.93 to 1.27, 5132 participants, 4 trials, moderate-quality evidence). Procalcitonin-guided management probably results in little or no difference in treatment failure in general practice compared to normal care (adjusted OR 0.95, 95% CI 0.73 to 1.24, 1008 participants, 2 trials, moderate-quality evidence), however it probably reduces treatment failure in the emergency department compared to usual care (adjusted OR 0.76, 95% CI 0.61 to 0.95, 2605 participants, 7 trials, moderate-quality evidence).The quality of evidence for interventions focused on clinician educational materials and decision support in reducing antibiotic prescribing in general practice was either low or very low (no pooled result reported) and trial results were highly heterogeneous, therefore we were unable draw conclusions about the effects of these interventions. The use of rapid viral diagnostics in emergency departments may have little or no effect on antibiotic prescribing (RR 0.86, 95% CI 0.61 to 1.22, 891 participants, 3 trials, low-quality evidence) and may result in little to no difference in reconsultation (RR 0.86, 95% CI 0.59 to 1.25, 200 participants, 1 trial, low-quality evidence).None of the trials in the included reviews reported on management costs for the treatment of an ARI or any associated complications. AUTHORS' CONCLUSIONS: We found evidence that CRP testing, shared decision making, and procalcitonin-guided management reduce antibiotic prescribing for patients with ARIs in primary care. These interventions may therefore reduce overall antibiotic consumption and consequently antibiotic resistance. There do not appear to be negative effects of these interventions on the outcomes of patient satisfaction and reconsultation, although there was limited measurement of these outcomes in the trials. This should be rectified in future trials.We could gather no information about the costs of management, and this along with the paucity of measurements meant that it was difficult to weigh the benefits and costs of implementing these interventions in practice.Most of this research was undertaken in high-income countries, and it may not generalise to other settings. The quality of evidence for the interventions of educational materials and tools for patients and clinicians was either low or very low, which prevented us from drawing any conclusions. High-quality trials are needed to further investigate these interventions.
Asunto(s)
Antibacterianos/uso terapéutico , Prescripción Inadecuada/prevención & control , Atención Primaria de Salud , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Literatura de Revisión como Asunto , Enfermedad Aguda , Proteína C-Reactiva/análisis , Calcitonina/sangre , Farmacorresistencia Bacteriana , Humanos , Sesgo de Publicación , Ensayos Clínicos Controlados Aleatorios como Asunto , Infecciones del Sistema Respiratorio/sangre , Infecciones del Sistema Respiratorio/virología , Virosis/diagnósticoRESUMEN
BACKGROUND: Delayed antibiotic prescribing reduces antibiotic use for acute respiratory infections in trials in general practice, but the uptake in clinical practice is low. The aim of the study was to identify facilitators and barriers to general practitioners' (GPs') use of delayed prescribing and to gain pharmacists' and the public's views about delayed prescribing in Australia. METHODS: This study used the Theoretical Domains Framework and the Behaviour Change Wheel to explore facilitators and barriers to delayed prescribing in Australia. Forty-three semi-structured, face-to-face interviews with general practitioners, pharmacists and patients were conducted. Responses were coded into domains of the Theoretical Domains Framework, and specific criteria from the Behaviour Change Wheel were used to identify which domains were relevant to increasing the use of delayed prescribing by GPs. RESULTS: The interviews revealed nine key domains that influence GPs' use of delayed prescribing: knowledge; cognitive and interpersonal skills; memory, attention and decision-making processes; optimism; beliefs about consequences; intentions; goals; emotion; and social influences: GPs knew about delayed prescribing; however, they did not use it consistently, preferring to bring patients back for review and only using it with patients in a highly selective way. Pharmacists would support GPs and the public in delayed prescribing but would fill the prescription if people insisted. The public said they would delay taking their antibiotics if asked by their GP and given the right information on managing symptoms and when to take antibiotics. CONCLUSIONS: Using a theory-driven approach, we identified nine key domains that influence GPs' willingness to provide a delayed prescription to patients with an acute respiratory infection presenting to general practice. These data can be used to develop a structured intervention to change this behaviour and thus reduce antibiotic use for acute respiratory infections in general practice.
Asunto(s)
Antibacterianos/uso terapéutico , Competencia Clínica , Toma de Decisiones Clínicas , Médicos Generales , Relaciones Médico-Paciente , Pautas de la Práctica en Medicina , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Espera Vigilante , Enfermedad Aguda , Adulto , Atención , Australia , Emociones , Femenino , Humanos , Intención , Masculino , Persona de Mediana Edad , Optimismo , Farmacéuticos , Teoría Psicológica , Investigación Cualitativa , Queensland , Factores de Tiempo , Adulto JovenRESUMEN
BACKGROUND: Acute upper respiratory tract infections (URTIs) are frequently managed in primary care settings. Although many are viral, and there is an increasing problem with antibiotic resistance, antibiotics continue to be prescribed for URTIs. Written patient information may be a simple way to reduce antibiotic use for acute URTIs. OBJECTIVES: To assess if written information for patients (or parents of child patients) reduces the use of antibiotics for acute URTIs in primary care. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, CINAHL, LILACS, Web of Science, clinical trials.gov, and the World Health Organization (WHO) trials registry up to July 2016 without language or publication restrictions. SELECTION CRITERIA: We included randomised controlled trials (RCTs) involving patients (or parents of child patients) with acute URTIs, that compared written patient information delivered immediately before or during prescribing, with no information. RCTs needed to have measured our primary outcome (antibiotic use) to be included. DATA COLLECTION AND ANALYSIS: Two review authors screened studies, extracted data, and assessed study quality. We could not meta-analyse included studies due to significant methodological and statistical heterogeneity; we summarised the data narratively. MAIN RESULTS: Two RCTs met our inclusion criteria, involving a total of 827 participants. Both studies only recruited children with acute URTIs (adults were not involved in either study): 558 children from 61 general practices in England and Wales; and 269 primary care doctors who provided data on 33,792 patient-doctor consultations in Kentucky, USA. The UK study had a high risk of bias due to lack of blinding and the US cluster-randomised study had a high risk of bias because the methods to allocate participants to treatment groups was not clear, and there was evidence of baseline imbalance.In both studies, clinicians provided written information to parents of child patients during primary care consultations: one trained general practitioners (GPs) to discuss an eight-page booklet with parents; the other conducted a factorial trial with two comparison groups (written information compared to usual care and written information plus prescribing feedback to clinicians compared to prescribing feedback alone). Doctors in the written information arms received 25 copies of two-page government-sponsored pamphlets to distribute to parents.Compared to usual care, we found moderate quality evidence (one study) that written information significantly reduced the number of antibiotics used by patients (RR 0.53, 95% CI 0.35 to 0.80; absolute risk reduction (ARR) 20% (22% versus 42%)) and had no significant effect on reconsultation rates (RR 0.79, 95% CI 0.47 to 1.32), or parent satisfaction with consultation (RR 0.95, 95% CI 0.87 to 1.03). Low quality evidence (two studies) demonstrated that written information also reduced antibiotics prescribed by clinicians (RR 0.47, 95% CI 0.28 to 0.78; ARR 21% (20% versus 41%); and RR 0.84, 95% CI 0.81 to 0.86; 9% ARR (45% versus 54%)). Neither study measured resolution of symptoms, patient knowledge about antibiotics for acute URTIs, or complications for this comparison.Compared to prescribing feedback, we found low quality evidence that written information plus prescribing feedback significantly increased the number of antibiotics prescribed by clinicians (RR 1.13, 95% CI 1.09 to 1.17; absolute risk increase 6% (50% versus 44%)). Neither study measured reconsultation rate, resolution of symptoms, patient knowledge about antibiotics for acute URTIs, patient satisfaction with consultation or complications for this comparison. AUTHORS' CONCLUSIONS: Compared to usual care, moderate quality evidence from one study showed that trained GPs providing written information to parents of children with acute URTIs in primary care can reduce the number of antibiotics used by patients without any negative impact on reconsultation rates or parental satisfaction with consultation. Low quality evidence from two studies shows that, compared to usual care, GPs prescribe fewer antibiotics for acute URTIs but prescribe more antibiotics when written information is provided alongside prescribing feedback (compared to prescribing feedback alone). There was no evidence addressing resolution of patients' symptoms, patient knowledge about antibiotics for acute URTIs, or frequency of complications.To fill evidence gaps, future studies should consider testing written information on antibiotic use for adults with acute URTIs in high- and low-income settings provided without clinician training and presented in different formats (such as electronic). Future study designs should endeavour to ensure blinded outcome assessors. Study aims should include measurement of the effect of written information on the number of antibiotics used by patients and prescribed by clinicians, patient satisfaction, reconsultation, patients' knowledge about antibiotics, resolution of symptoms, and complications.
Asunto(s)
Antibacterianos/uso terapéutico , Prescripción Inadecuada/prevención & control , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Enfermedad Aguda , Niño , Medicina General , Humanos , Prescripción Inadecuada/estadística & datos numéricos , Folletos , Padres , Educación del Paciente como Asunto/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto , Infecciones del Sistema Respiratorio/virología , Virosis/tratamiento farmacológicoRESUMEN
BACKGROUND: Antibiotic resistance is a major global public health threat. Most antibiotic prescriptions for human consumption in primary care are for acute respiratory tract infections (ARTIs). Australia continues to be a high prescriber of antibiotics, compared with other Organisation for Economic Cooperation and Development (OECD) countries. Implementation of evidence-based strategies to reduce antibiotic use in primary care is needed. Delayed prescribing is one evidence-based strategy that is underused. OBJECTIVE: This article describes delayed prescribing, the evidence for its effectiveness, how it works, how it could be implemented in Australia and what individual general practitioners (GPs) can do. DISCUSSION: Delayed prescribing, also called 'wait-and-see prescribing', is the process whereby a GP makes an antibiotic prescription available during the consultation, but asks the patient to delay its use to see if symptoms will resolve first. Evidence indicates that delayed prescribing is an effective strategy for reducing antibiotic use but requires implementation. Individual GPs can begin to use this strategy as a method of treating patients with ARTIs.
Asunto(s)
Antibacterianos/uso terapéutico , Prescripciones de Medicamentos , Medicina General/métodos , Atención Primaria de Salud/métodos , Espera Vigilante/métodos , Australia , Humanos , Infecciones del Sistema Respiratorio/tratamiento farmacológicoRESUMEN
BACKGROUND: Bronchiectasis is characterised by a widening of the airways, leading to excess mucus production and recurrent infection. It is more prevalent in women and those in middle age. Many patients with bronchiectasis do not adhere to treatments (medications, exercise and airway clearance) prescribed for their condition. The best methods to change these adherence behaviours have not been identified. OBJECTIVES: To assess the effects of interventions to enhance adherence to any aspect of treatment in adults with bronchiectasis in terms of adherence and health outcomes, such as pulmonary exacerbations, health-related quality of life and healthcare costs. SEARCH METHODS: We searched the Cochrane Airways Group Specialised Register (CAGR), which contains trial reports identified through systematic searches of CENTRAL, MEDLINE, EMBASE, CINAHL, AMED and PsycINFO, from inception to October 2015. SELECTION CRITERIA: We planned to include randomised controlled trials (RCTs) of adults with bronchiectasis that compared any intervention aimed at enhancing adherence versus no intervention, usual care or another adherence intervention. We excluded studies of those who had bronchiectasis due to cystic fibrosis. DATA COLLECTION AND ANALYSIS: Two review authors (AMcC and ET) independently screened titles, abstracts and full-texts of identified studies. MAIN RESULTS: Searches retrieved 36 studies reported in 37 articles; no eligible studies were identified. AUTHORS' CONCLUSIONS: We did not identify any studies that assessed the effect of interventions to enhance adherence to treatment in bronchiectasis. Adequately powered, well-designed trials of adherence interventions for bronchiectasis are needed.
Asunto(s)
Bronquiectasia/terapia , Cooperación del Paciente/psicología , Adulto , HumanosRESUMEN
BACKGROUND: Adherence to treatment is low in bronchiectasis and is associated with poorer health outcomes. Factors affecting adherence decisions have not been explored in patients with bronchiectasis. OBJECTIVE: We aimed to explore patients' perspectives on adherence, factors affecting adherence decision making and to develop a conceptual model explaining this decision-making process in adults with bronchiectasis. METHODS: Adults with bronchiectasis participated in one-to-one semi-structured interviews. Interviews were audio-recorded, transcribed verbatim and analysed independently by two researchers using thematic analysis. Data from core themes were extracted, categorized into factors affecting adherence decision making and used to develop the conceptual model. RESULTS: Participants' beliefs about treatment, the practical aspects of managing treatment, their trust in health-care professionals and acceptance of disease and treatment were important aspects of treatment adherence. The conceptual model demonstrated that adherence decisions were influenced by participants' individual balance of barriers and motivating factors (treatment-related, disease-related, health-care-related, personal and social factors). CONCLUSION: Adherence decision-making in bronchiectasis is complex, but there is the potential to enhance adherence by understanding patients' specific barriers and motivators to adherence and using this to tailor adherence strategies to individual patients and treatments.
Asunto(s)
Bronquiectasia/tratamiento farmacológico , Toma de Decisiones , Cumplimiento de la Medicación/psicología , Anciano , Femenino , Conocimientos, Actitudes y Práctica en Salud , Personal de Salud , Humanos , Masculino , Persona de Mediana Edad , Motivación , Investigación CualitativaRESUMEN
BACKGROUND: Low patient adherence to treatment is associated with poorer health outcomes in bronchiectasis. We sought to use the Theoretical Domains Framework (TDF) (a framework derived from 33 psychological theories) and behavioural change techniques (BCTs) to define the content of an intervention to change patients' adherence in bronchiectasis (Stage 1 and 2) and stakeholder expert panels to define its delivery (Stage 3). METHODS: We conducted semi-structured interviews with patients with bronchiectasis about barriers and motivators to adherence to treatment and focus groups or interviews with bronchiectasis healthcare professionals (HCPs) about their ability to change patients' adherence to treatment. We coded these data to the 12 domain TDF to identify relevant domains for patients and HCPs (Stage 1). Three researchers independently mapped relevant domains for patients and HCPs to a list of 35 BCTs to identify two lists (patient and HCP) of potential BCTs for inclusion (Stage 2). We presented these lists to three expert panels (two with patients and one with HCPs/academics from across the UK). We asked panels who the intervention should target, who should deliver it, at what intensity, in what format and setting, and using which outcome measures (Stage 3). RESULTS: Eight TDF domains were perceived to influence patients' and HCPs' behaviours: Knowledge, Skills, Beliefs about capability, Beliefs about consequences, Motivation, Social influences, Behavioural regulation and Nature of behaviours (Stage 1). Twelve BCTs common to patients and HCPs were included in the intervention: Monitoring, Self-monitoring, Feedback, Action planning, Problem solving, Persuasive communication, Goal/target specified:behaviour/outcome, Information regarding behaviour/outcome, Role play, Social support and Cognitive restructuring (Stage 2). Participants thought that an individualised combination of these BCTs should be delivered to all patients, by a member of staff, over several one-to-one and/or group visits in secondary care. Efficacy should be measured using pulmonary exacerbations, hospital admissions and quality of life (Stage 3). CONCLUSIONS: Twelve BCTs form the intervention content. An individualised selection from these 12 BCTs will be delivered to all patients over several face-to-face visits in secondary care. Future research should focus on developing physical materials to aid delivery of the intervention prior to feasibility and pilot testing. If effective, this intervention may improve adherence and health outcomes for those with bronchiectasis in the future.
Asunto(s)
Terapia Conductista/métodos , Cumplimiento de la Medicación , Teoría Psicológica , Anciano , Bronquiectasia/tratamiento farmacológico , Parto Obstétrico , Femenino , Grupos Focales , Personal de Salud/psicología , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Motivación , Embarazo , Investigación Cualitativa , Calidad de VidaRESUMEN
BACKGROUND: We aimed to determine adherence to inhaled antibiotics, other respiratory medicines and airway clearance and to determine the association between adherence to these treatments and health outcomes (pulmonary exacerbations, lung function and Quality of Life Questionnaire-Bronchiectasis [QOL-B]) in bronchiectasis after 12 months. METHODS: Patients with bronchiectasis prescribed inhaled antibiotics for Pseudomonas aeruginosa infection were recruited into a one-year study. Participants were categorised as "adherent" to medication (medication possession ratio ≥80% using prescription data) or airway clearance (score ≥80% in the Modified Self-Reported Medication-Taking Scale). Pulmonary exacerbations were defined as treatment with a new course of oral or intravenous antibiotics over the one-year study. Spirometry and QOL-B were completed at baseline and 12 months. Associations between adherence to treatment and pulmonary exacerbations, lung function and QOL-B were determined by regression analyses. RESULTS: Seventy-five participants were recruited. Thirty-five (53%), 39 (53%) and 31 (41%) participants were adherent to inhaled antibiotics, other respiratory medicines, and airway clearance, respectively. Twelve (16%) participants were adherent to all treatments. Participants who were adherent to inhaled antibiotics had significantly fewer exacerbations compared to non-adherent participants (2.6 vs 4, p = 0.00) and adherence to inhaled antibiotics was independently associated with having fewer pulmonary exacerbations (regression co-efficient = -0.51, 95% CI [-0.81,-0.21], p < 0.001). Adherence to airway clearance was associated with lower QOL-B Treatment Burden (regression co-efficient = -15.46, 95% CI [-26.54, -4.37], p < 0.01) and Respiratory Symptoms domain scores (regression co-efficient = -10.77, 95% CI [-21.45; -0.09], p < 0.05). There were no associations between adherence to other respiratory medicines and any of the outcomes tested. Adherence to treatment was not associated with FEV1 % predicted. CONCLUSIONS: Treatment adherence is low in bronchiectasis and affects important health outcomes including pulmonary exacerbations. Adherence should be measured as part of bronchiectasis management and future research should evaluate bronchiectasis-specific adherence strategies.
Asunto(s)
Antibacterianos/uso terapéutico , Bronquiectasia/terapia , Cooperación del Paciente/estadística & datos numéricos , Infecciones por Pseudomonas/tratamiento farmacológico , Terapia Respiratoria/métodos , Administración por Inhalación , Administración Oral , Anciano , Bronquiectasia/diagnóstico , Bronquiectasia/microbiología , Estudios de Cohortes , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Modelos Lineales , Masculino , Cumplimiento de la Medicación/estadística & datos numéricos , Persona de Mediana Edad , Distribución de Poisson , Estudios Prospectivos , Infecciones por Pseudomonas/diagnóstico , Calidad de Vida , Medición de Riesgo , Índice de Severidad de la Enfermedad , Esteroides/uso terapéutico , Resultado del TratamientoRESUMEN
OBJECTIVE: The objective of this review is to determine the prevalence and incidence of Mycoplasma genitalium infection. INTRODUCTION: Mycoplasma genitalium is a sexually transmitted pathogen that can cause reproductive health issues in men and women. Recent US Food and Drug Administration (FDA)-approved testing has improved the capability to more readily diagnose and treat this infection. Determining the incidence and prevalence of this sexually transmitted infection is imperative to better understand the epidemiologic implications and long-term consequences of this disease process. INCLUSION CRITERIA: Studies involving males and females of any age, race, or cultural background will be eligible. Studies conducted in any setting or geographical location that report on prevalence or incidence of Mycoplasma genitalium infection diagnosed by the FDA-approved Aptima Mycoplasma genitalium assay will be included. METHODS: The proposed systematic review will be conducted in accordance with JBI methodology for systematic reviews of prevalence and incidence, and in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. MEDLINE (PubMed), CINAHL (EBSCOhost), Embase, Web of Science, and Global Infectious Diseases and Epidemiology Network (GIDEON) databases will be searched, with no date limits. Prevalence and incidence data, experimental, quasi-experimental, observational, and descriptive studies will be included, and critically appraised by 2 independent reviewers. Data will be extracted using standardized JBI data extraction tools. If sufficient data are available, a meta-analysis will be conducted; otherwise, the findings will be presented in narrative format, including tables and figures to aid in data presentation, where appropriate. REVIEW REGISTRATION: PROSPERO CRD42023415457.
Asunto(s)
Infecciones por Mycoplasma , Mycoplasma genitalium , Masculino , Humanos , Femenino , Infecciones por Mycoplasma/diagnóstico , Infecciones por Mycoplasma/epidemiología , Infecciones por Mycoplasma/tratamiento farmacológico , Prevalencia , Incidencia , Revisiones Sistemáticas como Asunto , Metaanálisis como Asunto , Literatura de Revisión como AsuntoRESUMEN
Pixantrone and mitoxantrone are structurally related anticancer drugs which have been shown to generate covalent conjugates at apurinic/apyrimidinic (AP) sites in DNA. Mitoxantrone binding to AP sites induces DNA strand cleavage and inhibits the endonuclease activity of human AP endonuclease 1 (APE1). Here, pixantrone was demonstrated to have similar properties, but relative to mitoxantrone, it was significantly less potent in both DNA incision and APE1 inhibition. Consistent with these observations, pixantrone had ~ 15-fold lower affinity for DNA containing an AP site analogue, tetrahydrofuran, as measured by a Thiazole Orange (ThO) displacement assay.
RESUMEN
Mitoxantrone (1,4-dihydroxy-5,8-bis[2-(2-hydroxyethylamino)ethylamino]-anthracene-9,10-dione) is a clinically-relevant synthetic anthracenedione that functions as a topoisomerase II poison by trapping DNA double-strand break intermediates. Mitoxantrone binds to DNA via both stacking interactions with DNA bases and hydrogen bonding with the sugar-phosphate backbone. It has been shown that mitoxantrone inhibits apurinic/apyrimidinic (AP) endonuclease 1 (APE1)-catalyzed incision of DNA containing a tetrahydrofuran (THF) moiety and more recently, that mitoxantrone forms Schiff base conjugates at AP sites in DNA. In this study, mitoxantrone-mediated inhibition of APE1 at THF sites was shown to be consistent with preferential binding to, and thermal stabilization of DNA containing a THF site as compared to non-damaged DNA. Investigations into the properties of mitoxantrone at AP and 3' α,ß-unsaturated aldehyde sites demonstrated that in addition to being a potent inhibitor of APE1 at these biologically-relevant substrates (â¼ 0.5 µM IC50 on AP site-containing DNA), mitoxantrone also incised AP site-containing DNA by catalyzing ß- and ß/δ-elimination reactions. The efficiency of these reactions to generate the 3' α,ß-unsaturated aldehyde and 3' phosphate products was modulated by DNA structure. Although these cell-free reactions revealed that mitoxantrone can generate 3' phosphates, cells lacking polynucleotide kinase phosphatase did not show increased sensitivity to mitoxantrone treatment. Consistent with its ability to inhibit APE1 activity on DNAs containing either an AP site or a 3' α,ß-unsaturated aldehyde, combined exposures to clinically-relevant concentrations of mitoxantrone and a small molecule APE1 inhibitor revealed additive cytotoxicity. These data suggest that in a cellular context, mitoxantrone may interfere with APE1 DNA repair functions.
Asunto(s)
ADN , Mitoxantrona , Mitoxantrona/farmacología , ADN/metabolismo , Reparación del ADN , Aldehídos , Fosfatos , Endonucleasas/metabolismo , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismoRESUMEN
The base excision repair (BER) pathway is a precise and versatile mechanism of DNA repair that is initiated by DNA glycosylases. Endonuclease VIII-like 1 (NEIL1) is a bifunctional glycosylase/abasic site (AP) lyase that excises a damaged base and subsequently cleaves the phosphodiester backbone. NEIL1 is able to recognize and hydrolyze a broad range of oxidatively-induced base lesions and substituted ring-fragmented guanines, including aflatoxin-induced 8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxyaflatoxin B1 (AFB1-FapyGua). Due to NEIL1's protective role against these and other pro-mutagenic lesions, it was hypothesized that naturally occurring single nucleotide polymorphic (SNP) variants of NEIL1 could increase human risk for aflatoxin-induced hepatocellular carcinoma (HCC). Given that populations in South Asia experience high levels of dietary aflatoxin exposures and hepatitis B viral infections that induce oxidative stress, investigations on SNP variants of NEIL1 that occur in this region may have clinical implications. In this study, the most common South Asian variants of NEIL1 were expressed, purified, and functionally characterized. All tested variants exhibited activities and substrate specificities similar to wild type (wt)-NEIL1 on high-molecular weight DNA containing an array of oxidatively-induced base lesions. On short oligodeoxynucleotides (17-mers) containing either a site-specific apurinic/apyrimidinic (AP) site, thymine glycol (ThyGly), or AFB1-FapyGua, P206L-NEIL1 was catalytically comparable to wt-NEIL1, while the activities of NEIL1 variants Q67K and T278I on these substrates were ≈2-fold reduced. Variant T103A had a greatly diminished ability to bind to 17-mer DNAs, limiting the subsequent glycosylase and lyase reactions. Consistent with this observation, the rate of excision by T103A on 17-mer oligodeoxynucleotides containing ThyGly or AFB1-FapyGua could not be measured. However, the ability of T103A to excise ThyGly was improved on longer oligodeoxynucleotides (51-mers), with ≈7-fold reduced activity compared to wt-NEIL1. Our studies suggest that NEIL1 variant T103A may present a pathogenic phenotype that is limited in damage recognition, potentially increasing human risk for HCC.