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1.
Circulation ; 149(10): 734-743, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-37874908

RESUMO

BACKGROUND: Atrial fibrillation (AF) is common in patients undergoing transcatheter aortic valve replacement (TAVR) and is associated with increased risk of bleeding and stroke. While left atrial appendage occlusion (LAAO) is approved as an alternative to anticoagulants for stroke prevention in patients with AF, placement of these devices in patients with severe aortic stenosis, or when performed at the same time as TAVR, has not been extensively studied. METHODS: WATCH-TAVR (WATCHMAN for Patients with AF Undergoing TAVR) was a multicenter, randomized trial evaluating the safety and effectiveness of concomitant TAVR and LAAO with WATCHMAN in AF patients. Patients were randomized 1:1 to TAVR + LAAO or TAVR + medical therapy. WATCHMAN patients received anticoagulation for 45 days followed by dual antiplatelet therapy until 6 months. Anticoagulation was per treating physician preference for patients randomized to TAVR + medical therapy. The primary noninferiority end point was all-cause mortality, stroke, and major bleeding at 2 years between the 2 strategies. RESULTS: The study enrolled 349 patients (177 TAVR + LAAO and 172 TAVR + medical therapy) between December 2017 and November 2020 at 34 US centers. The mean age of patients was 81 years, and the mean scores for CHA2DS2-VASc and HAS-BLED (Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile INR, Elderly, Drugs/alcohol concomitantly) were 4.9 and 3.0, respectively. At baseline, 85.4% of patients were taking anticoagulants and 71.3% patients were on antiplatelet therapy. The cohorts were well-balanced for baseline characteristics. The incremental LAAO procedure time was 38 minutes, and the median contrast volume used for combined procedures was 119 mL versus 70 mL with TAVR alone. At the 24-month follow-up, 82.5% compared with 50.8% of patients were on any antiplatelet therapy, and 13.9% compared with 66.7% of patients were on any anticoagulation therapy in TAVR + LAAO compared with TAVR + medical therapy group, respectively. For the composite primary end point, TAVR + LAAO was noninferior to TAVR + medical therapy (22.7 versus 27.3 events per 100 patient-years for TAVR + LAAO and TAVR + medical therapy, respectively; hazard ratio, 0.86 [95% CI, 0.60-1.22]; Pnoninferiority<0.001). CONCLUSIONS: Concomitant WATCHMAN LAAO and TAVR is noninferior to TAVR with medical therapy in severe aortic stenosis patients with AF. The increased complexity and risks of the combined procedure should be considered when concomitant LAAO is viewed as an alternative to medical therapy for patients with AF undergoing TAVR. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03173534.


Assuntos
Estenose da Valva Aórtica , Apêndice Atrial , Fibrilação Atrial , Acidente Vascular Cerebral , Substituição da Valva Aórtica Transcateter , Humanos , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Substituição da Valva Aórtica Transcateter/efeitos adversos , Inibidores da Agregação Plaquetária/efeitos adversos , Apêndice Atrial/cirurgia , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Hemorragia/induzido quimicamente , Anticoagulantes/efeitos adversos , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/cirurgia , Resultado do Tratamento
2.
Mutagenesis ; 39(2): 96-118, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38183622

RESUMO

The N-nitrosamine, N-nitrosodimethylamine (NDMA), is an environmental mutagen and rodent carcinogen. Small levels of NDMA have been identified as an impurity in some commonly used drugs, resulting in several product recalls. In this study, NDMA was evaluated in an OECD TG-488 compliant Muta™Mouse gene mutation assay (28-day oral dosing across seven daily doses of 0.02-4 mg/kg/day) using an integrated design that assessed mutation at the transgenic lacZ locus in various tissues and at the endogenous Pig-a gene-locus, along with micronucleus frequencies in peripheral blood. Liver pathology was determined together with NDMA exposure in blood and liver. The additivity of mutation induction was assessed by including two acute single-dose treatment groups (i.e. 5 and 10 mg/kg dose on Day 1), which represented the same total dose as two of the repeat dose treatment groups. NDMA did not induce statistically significant increases in mean lacZ mutant frequency (MF) in bone marrow, spleen, bladder, or stomach, nor in peripheral blood (Pig-a mutation or micronucleus induction) when tested up to 4 mg/kg/day. There were dose-dependent increases in mean lacZ MF in the liver, lung, and kidney following 28-day repeat dosing or in the liver and kidney after a single dose (10 mg/kg). No observed genotoxic effect levels (NOGEL) were determined for the positive repeat dose-response relationships. Mutagenicity did not exhibit simple additivity in the liver since there was a reduction in MF following NDMA repeat dosing compared with acute dosing for the same total dose. Benchmark dose modelling was used to estimate point of departure doses for NDMA mutagenicity in Muta™Mouse and rank order target organ tissue sensitivity (liver > kidney or lung). The BMD50 value for liver was 0.32 mg/kg/day following repeat dosing (confidence interval 0.21-0.46 mg/kg/day). In addition, liver toxicity was observed at doses of ≥ 1.1 mg/kg/day NDMA and correlated with systemic and target organ exposure. The integration of these results and their implications for risk assessment are discussed.


Assuntos
Dimetilnitrosamina , Mutagênicos , Dimetilnitrosamina/toxicidade , Mutação , Mutagênicos/toxicidade , Dano ao DNA , Mutagênese
3.
Clin Radiol ; 79(11): e1288-e1295, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39174422

RESUMO

INTRODUCTION: Localisation methods for surgical excision of impalpable breast lesions have advanced in recent years, with increasing utilization of new wire-free technologies. The Hologic LOCalizer™ radiofrequency identification (RFID) tag is one such device; however, as is the case when new technologies are first introduced, little is known about clinical experiences, potential complications, and learning used to overcome perioperative challenges when changing from guidewires to RFID tags. This study reports shared learning experiences of clinicians using the LOCalizer™ as part of the national iBRA-NET localisation study. METHODS: This mixed-methods study captured shared-learning themes relating to LOCalizer™ usage as part of a multicentre prospective registry study, which collected data on each LOCalizer™ placement. Prospective, anonymized clinical and demographic data were collected and managed using a Research Electronic Data Capture (REDCap) database. Shared learning was captured prospectively as part of the registry study between January 2021 and July 2022, combined with a virtual qualitative webinar-style focus group. Learning events were then coded, grouped by theme, and suggestions for practice were produced. RESULTS: Twenty-four UK breast units submitted data on 1188 patient records pertaining to RFID-guided localisation between January 2021 and July 2022, of which 59 (5.0%) included a shared-learning event. The virtual webinar was attended by 108 healthcare professionals, including oncoplastic breast surgeons and breast radiologists. Shared-learning themes were categorized into preoperative, intraoperative, and postoperative events. CONCLUSIONS: By sharing learning outcomes associated with localisation techniques in this paper, the aim is to shorten the learning curve and potential for adverse events for users new to the LOCalizer™ technique.


Assuntos
Neoplasias da Mama , Dispositivo de Identificação por Radiofrequência , Sistema de Registros , Humanos , Neoplasias da Mama/cirurgia , Neoplasias da Mama/diagnóstico por imagem , Feminino , Estudos Prospectivos , Reino Unido , Pessoa de Meia-Idade , Adulto , Idoso , Mama/cirurgia , Mama/diagnóstico por imagem
4.
Regul Toxicol Pharmacol ; 150: 105647, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38777301

RESUMO

Multiple international guidelines exist that describe both quality and safety considerations for the control of the broad spectrum of impurities inherent to drug substance and product manufacturing processes. However, regarding non-mutagenic impurities (NMI) the most relevant ICH Q3A/B guidelines are not applicable during early phases of drug development leading to confusion about acceptable limits at this stage. Thus, there is need for more flexible approaches that ensure that patient safety remains paramount, while taking into consideration the limited duration of exposure. An EFPIA survey, which collected quantitative data from different types of studies applied to qualify impurities in accordance with ICH Q3A, shows that no toxicities could be attributed to any of the 467 impurities at any tested level in vivo. This data combined with earlier published toxicological datasets encompassing drug substances and intermediates, food related substances and chemicals provide convincing evidence that for NMIs, the application of a generic 5 mg/day limit for an exposure duration <6 months, and a 1 mg/day generic limit for life-long exposure, provides sufficient margins to ensure patient safety. Hence, application of these absolute limits to trigger qualification studies (instead of the relative limits described in Q3A/B), is considered warranted. This approach will prevent conduct of unnecessary dedicated impurity qualification studies and the resulting use of animals.


Assuntos
Contaminação de Medicamentos , Contaminação de Medicamentos/prevenção & controle , Humanos , Animais , Medição de Risco , Guias como Assunto
5.
Regul Toxicol Pharmacol ; 150: 105644, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38761968

RESUMO

ICH Q3A/B guidelines are not intended for application during the clinical research phase of development and durationally adjusted qualification thresholds are not included. A central tenet of ICH Q3A is that lifetime exposure to 1 mg/day of an unqualified non-mutagenic impurity (NMI) is not a safety concern. An analysis of in vivo toxicology data from 4878 unique chemicals with established NO(A)ELs was conducted to determine whether durationally adjusted qualification limits can be supported. Although not recommended in ICH Q3A/B, a conservative approach was taken by using allometric scaling in the analysis. Following allometric scaling of the 5th percentile of the distribution of NO(A)ELs from available chronic toxicology studies, it was reconfirmed that there is a safety basis for the 1 mg/day qualification threshold in ICH Q3A. Additionally, allometric scaling of the 5th percentile of the distribution of NO(A)ELs from sub-acute and sub-chronic toxicology studies could support acceptable limits of 20 and 5 mg/day for an unqualified NMI for dosing durations of less than or greater than one month, respectively. This analysis supports durationally adjusted NMI qualification thresholds for pharmaceuticals that protect patient safety and contribute to 3Rs efforts for qualifying impurities using new approach methods.


Assuntos
Contaminação de Medicamentos , Humanos , Animais , Medição de Risco , Nível de Efeito Adverso não Observado , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/normas
6.
Regul Toxicol Pharmacol ; 154: 105704, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39326488

RESUMO

The carcinogenicity potency categorization approach (CPCA) derived and harmonized by Health Authorities was a significant milestone, as it defined molecular properties that allowed for the rapid evaluation of the chemical structures of N-nitrosamine drug substance related impurities (NDSRIs) and the assignment of associated lifetime Acceptable Intake (AI) limits to inform on appropriate impurity control strategies in certain drug products. Nonetheless, it is important to continue to refine and improve on the CPCA based upon data-derived evidence. Herein, we focus on the default CPCA AI for NDSRIs, which is largely based on the small molecule N-nitrosamines (NAs). Considering the carcinogenic potency of NAs with a molecular weight >200 Da (NDSRIs molecular weight is typically 200-600 Da), we propose that in the absence of any compound specific data, the lowest lifetime Acceptable Intake for NAs, such as NDSRIs, should be 10x less (i.e., 150 ng/day) than the ICH M7 Threshold of Toxicological Concern of 1500 ng/day, (even for NDSRIs that are considered CPCA Category 1 and 2) which would conservatively result in a theoretical cancer risk of <1 in 100,000.

7.
Toxicol Appl Pharmacol ; 459: 116342, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36502871

RESUMO

Functional changes to cardiomyocytes are undesirable during drug discovery and identifying the inotropic effects of compounds is hence necessary to decrease the risk of cardiovascular adverse effects in the clinic. Recently, approaches leveraging calcium transients in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have been developed to detect contractility changes, induced by a variety of mechanisms early during drug discovery projects. Although these approaches have been able to provide some predictive ability, we hypothesised that using additional waveform parameters could offer improved insights, as well as predictivity. In this study, we derived 25 parameters from each calcium transient waveform and developed a modified Random Forest method to predict the inotropic effects of the compounds. In total annotated data for 48 compounds were available for modelling, out of which 31 were inotropes. The results show that the Random Forest model with a modified purity criterion performed slightly better than an unmodified algorithm in terms of the Area Under the Curve, giving values of 0.84 vs 0.81 in a cross-validation, and outperformed the ToxCast Pipeline model, for which the highest value was 0.76 when using the best-performing parameter, PW10. Our study hence demonstrates that more advanced parameters derived from waveforms, in combination with additional machine learning methods, provide improved predictivity of cardiovascular risk associated with inotropic effects.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Células-Tronco Pluripotentes Induzidas , Humanos , Miócitos Cardíacos , Cálcio , Aprendizado de Máquina
8.
J Med Genet ; 59(2): 133-140, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33568438

RESUMO

BACKGROUND: Women testing positive for BRCA1/2 pathogenic variants have high lifetime risks of breast cancer (BC) and ovarian cancer. The effectiveness of risk reducing surgery (RRS) has been demonstrated in numerous previous studies. We evaluated long-term uptake, timing and effectiveness of risk reducing mastectomy (RRM) and bilateral salpingo-oophorectomy (RRSO) in healthy BRCA1/2 carriers. METHODS: Women were prospectively followed up from positive genetic test (GT) result to censor date. χ² testing compared categorical variables; Cox regression model estimated HRs and 95% CI for BC/ovarian cancer cases associated with RRS, and impact on all-cause mortality; Kaplan-Meier curves estimated cumulative RRS uptake. The annual cancer incidence was estimated by women-years at risk. RESULTS: In total, 887 women were included in this analysis. Mean follow-up was 6.26 years (range=0.01-24.3; total=4685.4 women-years). RRS was performed in 512 women, 73 before GT. Overall RRM uptake was 57.9% and RRSO uptake was 78.6%. The median time from GT to RRM was 18.4 months, and from GT to RRSO-10.0 months. Annual BC incidence in the study population was 1.28%. Relative BC risk reduction (RRM versus non-RRM) was 94%. Risk reduction of ovarian cancer (RRSO versus non-RRSO) was 100%. CONCLUSION: Over a 24-year period, we observed an increasing number of women opting for RRS. We showed that the timing of RRS remains suboptimal, especially in women undergoing RRSO. Both RRM and RRSO showed a significant effect on relevant cancer risk reduction. However, there was no statistically significant RRSO protective effect on BC.


Assuntos
Neoplasias da Mama/prevenção & controle , Genes BRCA1 , Genes BRCA2 , Neoplasias Ovarianas/prevenção & controle , Procedimentos Cirúrgicos Profiláticos , Salpingo-Ooforectomia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/genética , Feminino , Seguimentos , Heterozigoto , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/genética , Mastectomia Profilática , Estudos Prospectivos , Medição de Risco , Adulto Jovem
9.
Surgeon ; 21(2): 128-134, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35551871

RESUMO

BACKGROUND & OBJECTIVES: Sentinel lymph node biopsy (SLNB) is an accurate and reliable method for staging the axilla in early breast cancer. The gold standard technique for localizing the sentinel lymph node (SLN) is the use of radioisotope with or without blue dye. However, this technique has its limitations. Various alternatives have been explored to overcome the disadvantages of the standard SLNB technique and superparamagnetic iron oxide mapping agents have garnered significant attention. The SMART study aims to compare the magnetic technique using the superparamagnetic iron oxide particles (SPIO, Sienna+®) to the radioisotope technique (Tc99) +/- blue dye, for SLN identification in patients with early breast cancer. METHODS: A prospective, multicenter study was done that recruited 109 clinically node-negative early-stage breast cancer patients from five centres in the United Kingdom (UK). The patients received radioisotope ± blue dye injections, followed by intraoperative injection of magnetic tracer prior to SLNB. The sentinel node identification rate was compared between the magnetic and standard techniques to evaluate detection rate (per patient and per node), non-inferiority and concordance. RESULTS: Data was analysed for 107 patients. The per patient detection rate was 98.13% (105/107) when using the magnetic tracer and 92.26% (103/107) when using the standard technique. The nodal detection rate was 93.07% (188/202 nodes) when using the magnetic tracer and 96.53% (195/202) when using the standard technique. Of the 31 patients with positive sentinel lymph nodes (SLNs), all 31 (100%) were detected by both techniques. CONCLUSION: Our study demonstrates that the magnetic technique is a feasible method for SLNB, with an identification rate that is not inferior to the standard technique. The magnetic technique offers a suitable alternative to the standard technique thereby avoiding the need for the complexities of nuclear medicine, the hazards of radiation and the anaphylaxis risk of blue dye.


Assuntos
Neoplasias da Mama , Linfonodo Sentinela , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Linfonodo Sentinela/diagnóstico por imagem , Linfonodo Sentinela/cirurgia , Linfonodo Sentinela/patologia , Axila/patologia , Estudos Prospectivos , Linfonodos/patologia , Biópsia de Linfonodo Sentinela/métodos , Radioisótopos , Nanopartículas Magnéticas de Óxido de Ferro
10.
Ecol Indic ; 154: 1-15, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38274645

RESUMO

Ecosystem management requires a systematic, holistic approach that considers ecological and social outcomes. Effective restoration practices promote a balance of ecological and social goals by addressing ecological integrity, efficiently maximizing benefits while minimizing investment, and encompassing collaborative stakeholder engagement. Socio-ecological assessments can inform adaptive management and be utilized to prioritize restoration activities and monitor restoration effectiveness. In estuarine systems, socio-ecological assessments should evaluate the ability of habitats to support both ecologically and locally important species. The composite measure presented utilizes a combination of ecological and social measures to characterize ecological suitability for individual and multiple Gulf of Mexico estuarine species. The ecological suitability value (ES) for a given spatial unit is based on a suite of biophysical measures of the quality and extent of suitable habitat for each species, the species' trophic importance in a food web context, and the importance of each species in relation to stakeholder values and benefits. ES values for individual spatial units can be aggregated to estimate the distribution of ecological suitability at the estuarine scale. The ES values are calculated using examples for each step in the process. The information provided by ecological suitability characterizations can support restoration prioritization decisions for Gulf of Mexico estuaries and can provide a baseline measure to gauge restoration effectiveness over time to inform cumulative restoration assessments.

11.
Br J Surg ; 109(3): 274-282, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-35089321

RESUMO

BACKGROUND: Wire localization is historically the most common method for guiding excision of non-palpable breast lesions, but there are limitations to the technique. Newer technologies such as magnetic seeds may allow some of these challenges to be overcome. The aim was to compare safety and effectiveness of wire and magnetic seed localization techniques. METHODS: Women undergoing standard wire or magnetic seed localization for non-palpable lesions between August 2018 and August 2020 were recruited prospectively to this IDEAL stage 2a/2b platform cohort study. The primary outcome was effectiveness defined as accurate localization and removal of the index lesion. Secondary endpoints included safety, specimen weight and reoperation rate for positive margins. RESULTS: Data were accrued from 2300 patients in 35 units; 2116 having unifocal, unilateral breast lesion localization. Identification of the index lesion in magnetic-seed-guided (946 patients) and wire-guided excisions (1170 patients) was 99.8 versus 99.1 per cent (P = 0.048). There was no difference in overall complication rate. For a subset of patients having a single lumpectomy only for lesions less than 50 mm (1746 patients), there was no difference in median closest margin (2 mm versus 2 mm, P = 0.342), re-excision rate (12 versus 13 per cent, P = 0.574) and specimen weight in relation to lesion size (0.15 g/mm2versus 0.138 g/mm2, P = 0.453). CONCLUSION: Magnetic seed localization demonstrated similar safety and effectiveness to those of wire localization. This study has established a robust platform for the comparative evaluation of new localization devices.


Assuntos
Neoplasias da Mama/cirurgia , Imãs , Mastectomia Segmentar/métodos , Idoso , Neoplasias da Mama/patologia , Feminino , Marcadores Fiduciais , Humanos , Imãs/efeitos adversos , Margens de Excisão , Mastectomia Segmentar/efeitos adversos , Mastectomia Segmentar/instrumentação , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Complicações Pós-Operatórias , Estudos Prospectivos
12.
Regul Toxicol Pharmacol ; 135: 105247, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35998738

RESUMO

Under ICH M7, impurities are assessed using the bacterial reverse mutation assay (i.e., Ames test) when predicted positive using in silico methodologies followed by expert review. N-Nitrosamines (NAs) have been of recent concern as impurities in pharmaceuticals, mainly because of their potential to be highly potent mutagenic carcinogens in rodent bioassays. The purpose of this analysis was to determine the sensitivity of the Ames assay to predict the carcinogenic outcome with curated proprietary Vitic (n = 131) and Leadscope (n = 70) databases. NAs were selected if they had corresponding rodent carcinogenicity assays. Overall, the sensitivity/specificity of the Ames assay was 93-97% and 55-86%, respectively. The sensitivity of the Ames assay was not significantly impacted by plate incorporation (84-89%) versus preincubation (82-89%). Sensitivity was not significantly different between use of rat and hamster liver induced S9 (80-93% versus 77-96%). The sensitivity of the Ames is high when using DMSO as a solvent (87-88%). Based on the analysis of these databases, the Ames assay conducted under OECD 471 guidelines is highly sensitive for detecting the carcinogenic hazards of NAs.


Assuntos
Dimetil Sulfóxido , Nitrosaminas , Animais , Bactérias , Bioensaio , Carcinógenos/toxicidade , Cricetinae , Mutação , Nitrosaminas/metabolismo , Nitrosaminas/toxicidade , Preparações Farmacêuticas , Ratos , Roedores/metabolismo , Solventes
13.
Ecol Indic ; 143: 1-11, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36504635

RESUMO

A combination of ecological and socio-economic outcome indicators is essential for understanding and assessing the effectiveness of the remediation and restoration of degraded ecosystems and revitalizing communities that could benefit from these ecosystem management activities. In this paper, we propose and develop a conceptual approach to characterize ecological suitability that incorporates ecological attributes that support ecosystem structural diversity and functionality, stakeholder values and perceptions, and the benefits derived from ecosystem goods and services. A structured literature review was used to identify existing restoration frameworks and indicators to inform the conceptual foundation for characterizing ecological suitability. The structure of the conceptual approach primarily builds from ecological and social attributes in the International Principles and Standards for the Practice of Ecological Restoration (Gann et al., 2019). We provide a conceptual example of the ecological suitability approach in estuaries. This example is based on habitat suitability and food web characterizations in combination with the provisioning of ecosystem services and desired social benefits to prioritize and evaluate restoration effectiveness. This foundational work sets the stage for developing a composite measure of ecological suitability. The holistic conceptual approach presented complements existing information regarding restoration effectiveness evaluations. Characterizing ecological suitability is a novel way to incorporate ecological and social information and communicate potential restoration outcomes to ecosystem managers and stakeholders.

14.
J Indian Assoc Pediatr Surg ; 27(3): 340-344, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35733589

RESUMO

Purpose: The purpose of this study was to study the presentation of patients who underwent Meckel's diverticulectomy (MD) and utility of pertechnetate Meckel's scan in the diagnosis of MD. Methods: The clinical presentation of a retrospective cohort of patients who underwent MD from January 2007 to December 2019 was studied. The modes of presentation, treatment, and the diagnostic utility of pertechnetate Meckel's scans were evaluated. False-positive and false-negative scans were reviewed. The presence of gastric mucosa on histology of Meckel's was correlated with presentation as gastrointestinal bleeding and positive scan results. Results: Ninety-nine patients underwent MD. Thirty-five out of 263 (13.3%) Meckel's scans done were positive. There was a male preponderance (86.9%). The peak age of presentation was 0-4 years (rectal bleeding or intestinal obstruction). Only a third of the patients with Meckel's diverticulum Meckel's had a preoperative diagnosis of Meckel's. The sensitivity/specificity of Meckel's scan was higher in patients presenting with painless rectal bleeding. Seven patients were false positive (weak tracer uptake or ectopic uptake) and five were false negative. Two patients with false-negative Meckel's scan, having gastrointestinal bleeding had gastric mucosa on histology of Meckel's. Conclusion: Meckel's diverticulum has a male predominance. Meckel's scan has a high sensitivity in the children presenting with fresh painless rectal bleeding but is of limited use in the diagnosis of Meckel's diverticulum in other forms of presentations. False-positive scans can be anticipated in the presence of weak or ectopic uptake. False-negative scans can occur even in the presence of bleeding and in spite of the presence of gastric mucosa in the Meckel's diverticulum. Laparoscopy is a useful tool in diagnosis and treatment.

15.
Breast Cancer Res Treat ; 185(1): 13-20, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32914355

RESUMO

INTRODUCTION: Breast conserving surgery of impalpable breast lesions requires safe and effective localisation techniques. Wire localisation has traditionally been used, but has limitations. Newer techniques are now being introduced to mitigate this. The iBRA-NET group aims to robustly evaluate these new techniques in well-designed prospective studies. We report the first phase of this evaluation, a survey to establish current practice and service provision of breast localisation techniques in the UK. METHODS: A national practice questionnaire was designed using 'SurveyMonkey®' and was circulated to UK breast surgeons via the Association of Breast Surgery and the Mammary Fold. The questionnaire was live from 6th October 2018 to 6th April 2019. Only one response per unit was requested to reflect the unit's practice. RESULTS: Complete responses were received from 98 breast units across the UK. Wires were the mostly commonly used localisation technique (n = 82) with fewer units using Magseed® (n = 9), Radioguided Occult Lesion Localisation (n = 5) and Radioiodine Seed Localisation (n = 2). There was significant variation in practice and logistics involved. Frequent delays and theatre overruns were reported in 39 and 16 units, respectively. The median satisfaction score of the current technique was 7 out of 10. The main perceived limitation of existing localisation methods was logistics affecting theatre scheduling and the main barrier to introducing a new technique was cost. CONCLUSION: Wires are currently the most commonly used localisation technique but are associated with significant logistical issues. Newer techniques may offer a better solution but will need robust evaluation before they are adopted to ensure safety and efficacy.


Assuntos
Neoplasias da Mama , Radioisótopos do Iodo , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Feminino , Humanos , Estudos Prospectivos , Inquéritos e Questionários , Reino Unido
16.
Breast Cancer Res Treat ; 189(3): 677-687, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34312777

RESUMO

PURPOSE: Women at increased familial breast cancer risk have been offered screening starting at an earlier age and increased frequency than national Screening Programmes for over 30 years. There are limited data on longer-term largescale implementation of this approach on cancer diagnosis. METHODS: Women at our institution at ≥ 17% lifetime breast cancer risk have been offered enhanced screening with annual mammography starting at age 35 or 5-years younger than youngest affected relative, with upper age limit 50 for moderate and 60 for high-risk. Breast cancer pathology, stage and receptor status were assessed as well as survival from cancer diagnosis by Kaplan-Meier analysis. RESULTS: Overall 14,311 women were seen and assessed for breast cancer risk, with 649 breast cancers occurring in 129,119 years follow up (post-prevalent annual incidence = 4.55/1000). Of 323/394 invasive breast cancers occurring whilst on enhanced screening, most were lymph-node negative (72.9%), T1 (≤ 20 mm, 73.2%) and stage-1 (61.4%), 126/394 stage2-4 (32%). 10-year breast cancer specific survival was 91.3% (95% CI 87.4-94.0) better than the 75.9% (95% CI 74.9-77.0) published for England in 2013-2017. As expected, survival was significantly better for women with screen detected cancers (p < 0.001). Ten-year survival was particularly good for those diagnosed ≤ 40 at 93.8% (n = 75; 95% CI 84.2-97.6). Women with lobular breast cancers had worse 10-year survival at 85.9% (95% CI 66.7-94.5). Breast cancer specific survival was good for 119 BRCA1/2 carriers with 20-year survival in BRCA1:91.2% (95% CI 77.8-96.6) and 83.8% (62.6-93.5) for BRCA2. CONCLUSIONS: Targeted breast screening in women aged 30-60 years at increased familial risk is associated with good long-term survival that is substantially better than expected from population data.


Assuntos
Neoplasias da Mama , Adulto , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Detecção Precoce de Câncer , Feminino , Humanos , Incidência , Imageamento por Ressonância Magnética , Mamografia , Programas de Rastreamento , Mutação
17.
Regul Toxicol Pharmacol ; 126: 105023, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34363920

RESUMO

The presence of impurities in drugs is unavoidable. As impurities offer no direct benefit to the patient, it is critical that impurities do not compromise patient safety. Current guidelines on the derivation of acceptable impurity levels leave aspects of calculations open for interpretation, resulting in inconsistencies across industry and regulators. To understand current impurity qualification practices from a safety standpoint, regulatory expectations and the safety risk that impurities pose, the IQ DruSafe Impurities Working Group (WG) conducted a pharmaceutical industry-wide survey. Survey results highlighted areas that could benefit from harmonization, including nonclinical species/sex selection and the application of adjustment factors (i.e., body surface area). Recommendations for alignment on these topics is included in this publication. Additionally, the WG collated repeat-dose toxicity information for 181 starting materials and intermediates, reflective of pharmaceutical impurities, to understand the toxicological risks they generally pose in relation to the drug substance (DS) and the assumptions surrounding the calculation of qualified impurity levels. An evaluation of this dataset and the survey were used to harmonize how to calculate a safe limit for an impurity based on toxicology testing of the impurity when present within the DS.


Assuntos
Contaminação de Medicamentos , Indústria Farmacêutica/normas , Guias como Assunto/normas , Internacionalidade , Bases de Dados Factuais , Relação Dose-Resposta a Droga , Humanos , Modelos Animais , Segurança do Paciente , Medição de Risco , Testes de Toxicidade/normas
18.
Syst Biol ; 68(6): 859-875, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31140573

RESUMO

Theory predicts that sexually dimorphic traits under strong sexual selection, particularly those involved with intersexual signaling, can accelerate speciation and produce bursts of diversification. Sexual dichromatism (sexual dimorphism in color) is widely used as a proxy for sexual selection and is associated with rapid diversification in several animal groups, yet studies using phylogenetic comparative methods to explicitly test for an association between sexual dichromatism and diversification have produced conflicting results. Sexual dichromatism is rare in frogs, but it is both striking and prevalent in African reed frogs, a major component of the diverse frog radiation termed Afrobatrachia. In contrast to most other vertebrates, reed frogs display female-biased dichromatism in which females undergo color transformation, often resulting in more ornate coloration in females than in males. We produce a robust phylogeny of Afrobatrachia to investigate the evolutionary origins of sexual dichromatism in this radiation and examine whether the presence of dichromatism is associated with increased rates of net diversification. We find that sexual dichromatism evolved once within hyperoliids and was followed by numerous independent reversals to monochromatism. We detect significant diversification rate heterogeneity in Afrobatrachia and find that sexually dichromatic lineages have double the average net diversification rate of monochromatic lineages. By conducting trait simulations on our empirical phylogeny, we demonstrate that our inference of trait-dependent diversification is robust. Although sexual dichromatism in hyperoliid frogs is linked to their rapid diversification and supports macroevolutionary predictions of speciation by sexual selection, the function of dichromatism in reed frogs remains unclear. We propose that reed frogs are a compelling system for studying the roles of natural and sexual selection on the evolution of sexual dichromatism across micro- and macroevolutionary timescales.


Assuntos
Anuros/classificação , Filogenia , Pigmentação , África , Animais , Anuros/fisiologia , Evolução Biológica , Feminino , Masculino , Caracteres Sexuais
19.
Ecol Appl ; 30(4): e02085, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31991504

RESUMO

Mangrove forests are among the world's most productive and carbon-rich ecosystems. Despite growing understanding of factors controlling mangrove forest soil carbon stocks, there is a need to advance understanding of the speed of peat development beneath maturing mangrove forests, especially in created and restored mangrove forests that are intended to compensate for ecosystem functions lost during mangrove forest conversion to other land uses. To better quantify the rate of soil organic matter development beneath created, maturing mangrove forests, we measured ecosystem changes across a 25-yr chronosequence. We compared ecosystem properties in created, maturing mangrove forests to adjacent natural mangrove forests. We also quantified site-specific changes that occurred between 2010 and 2016. Soil organic matter accumulated rapidly beneath maturing mangrove forests as sandy soils transitioned to organic-rich soils (peat). Within 25 yr, a 20-cm deep peat layer developed. The time required for created mangrove forests to reach equivalency with natural mangrove forests was estimated as (1) <15 yr for herbaceous and juvenile vegetation, (2) ~55 yr for adult trees, (3) ~25 yr for the upper soil layer (0-10 cm), and (4) ~45-80 yr for the lower soil layer (10-30 cm). For soil elevation change, the created mangrove forests were equivalent to or surpassed natural mangrove forests within the first 5 yr. A comparison to chronosequence studies from other ecosystems indicates that the rate of soil organic matter accumulation beneath maturing mangrove forests may be among the fastest globally. In most peatland ecosystems, soil organic matter formation occurs slowly (over centuries, millennia); however, these results show that mangrove peat formation can occur within decades. Peat development, primarily due to subsurface root accumulation, enables mangrove forests to sequester carbon, adjust their elevation relative to sea level, and adapt to changing conditions at the dynamic land-ocean interface. In the face of climate change and rising sea levels, coastal managers are increasingly concerned with the longevity and functionality of coastal restoration efforts. Our results advance understanding of the pace of ecosystem development in created, maturing mangrove forests, which can improve predictions of mangrove forest responses to global change and ecosystem restoration.


Assuntos
Ecossistema , Áreas Alagadas , Carbono , Mudança Climática , Florestas , Solo
20.
Appl Opt ; 59(22): G185-G203, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32749332

RESUMO

In April of 1972, Professor Roland Shack presented a series of four colloquium talks at the Optical Sciences Center at the University of Arizona in which he reformulated scalar diffraction theory in terms of the direction cosines of the propagation vectors of the angular spectrum of plane waves described by the Fourier integral transform of the diffracting aperture. The fourth lecture, entitled Radiometry and Lambert's Law, described diffuse reflectance and surface scatter phenomena as merely a diffraction phenomenon caused by random phase variations in the system pupil function. In 1974, he elegantly condensed these four lectures into a single colloquium talk entitled A Global View of Diffraction. This paper is intended to provide a compilation showing the further development of that work over the last 46 years.

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