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1.
Ecol Appl ; 31(3): e02290, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33426701

RESUMO

Soil organic carbon (SOC) regulates terrestrial ecosystem functioning, provides diverse energy sources for soil microorganisms, governs soil structure, and regulates the availability of organically bound nutrients. Investigators in increasingly diverse disciplines recognize how quantifying SOC attributes can provide insight about ecological states and processes. Today, multiple research networks collect and provide SOC data, and robust, new technologies are available for managing, sharing, and analyzing large data sets. We advocate that the scientific community capitalize on these developments to augment SOC data sets via standardized protocols. We describe why such efforts are important and the breadth of disciplines for which it will be helpful, and outline a tiered approach for standardized sampling of SOC and ancillary variables that ranges from simple to more complex. We target scientists ranging from those with little to no background in soil science to those with more soil-related expertise, and offer examples of the ways in which the resulting data can be organized, shared, and discoverable.


Assuntos
Carbono , Solo , Sequestro de Carbono , Ecossistema , Nutrientes
2.
Oecologia ; 194(4): 659-672, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33141324

RESUMO

The impacts of invasive species on biodiversity may be mitigated or exacerbated by abiotic environmental changes. Invasive plants can restructure soil fungal communities with important implications for native biodiversity and nutrient cycling, yet fungal responses to invasion may depend on numerous anthropogenic stressors. In this study, we experimentally invaded a long-term soil warming and simulated nitrogen deposition experiment with the widespread invasive plant Alliaria petiolata (garlic mustard) and tested the responses of soil fungal communities to invasion, abiotic factors, and their interaction. We focused on the phytotoxic garlic mustard because it suppresses native mycorrhizae across forests of North America. We found that invasion in combination with warming, but not under ambient conditions or elevated nitrogen, significantly reduced soil fungal biomass and ectomycorrhizal relative abundances and increased relative abundances of general soil saprotrophs and fungal genes encoding for hydrolytic enzymes. These results suggest that warming potentially exacerbates fungal responses to plant invasion. Soils collected from uninvaded and invaded plots across eight forests spanning a 4 °C temperature gradient further demonstrated that the magnitude of fungal responses to invasion was positively correlated with mean annual temperature. Our study is one of the first empirical tests to show that the impacts of invasion on fungal communities depends on additional anthropogenic pressures and were greater in concert with warming than under elevated nitrogen or ambient conditions.


Assuntos
Micobioma , Micorrizas , Nitrogênio/análise , América do Norte , Solo , Microbiologia do Solo
3.
J Appl Microbiol ; 126(1): 79-86, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30160334

RESUMO

AIMS: Disulfiram (Antabuse™) and its metabolites formed in vivo were evaluated as antibacterial agents against thirty species of Gram-positive and Gram-negative bacteria. The synergistic potential of disulfiram (DSF) and metabolite diethyldithiocarbamate (DDTC) with approved antibiotics were also compared by isobologram (checkerboard) analysis. METHODS AND RESULTS: Standard microdilution susceptibility testing showed that most DSF metabolites did not possess appreciable antibacterial activity except for DDTC in Bacillus anthracis. Checkerboard studies revealed similarities between the combination drug effects of DSF and DDTC with standard antibiotics. CONCLUSIONS: It was concluded from the susceptibility data that the metabolites would not extend the antibacterial spectrum of DSF in vivo. The data also suggest that the DDTC by-product of DSF metabolism potentiates the antibacterial activity of DSF as both a standalone and combination agent. SIGNIFICANCE AND IMPACT OF THE STUDY: The study provides a greater understanding of the antibacterial effects of Antabuse and its metabolites. This research also demonstrates the potential application of DSF as an antibiotic adjuvant for the treatment of resistant staph infections.


Assuntos
Antibacterianos/farmacologia , Dissulfiram/farmacologia , Ditiocarb/farmacologia , Antibacterianos/química , Antibacterianos/metabolismo , Dissulfiram/química , Dissulfiram/metabolismo , Ditiocarb/química , Ditiocarb/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento
5.
Anaesthesia ; 72(3): 317-327, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28054356

RESUMO

Postoperative pulmonary complications are common, with a reported incidence of 2-40%, and are associated with adverse outcomes that include death, longer hospital stay and reduced long-term survival. Enhanced recovery is now a standard of care for patients undergoing elective major surgery. Despite the high prevalence of pulmonary complications in this population, few elements of enhanced recovery specifically address reducing these complications. In 2013, a prevalence audit confirmed a postoperative pulmonary complication rate of 16/83 (19.3%) in patients undergoing elective major surgery who were admitted to critical care postoperatively. A quality improvement team developed and implemented ERAS+, an innovative model of peri-operative care combining elements of enhanced recovery with specific measures aimed at reducing pulmonary complications. ERAS+ was introduced in June 2014, with full implementation in September 2014. Patients were screened during full ERAS+ implementation and again one year following implementation. Following ERAS+ implementation, postoperative pulmonary complications reduced to 24/228 (10.5%). Sustained improvement was evident one year after implementation, with a pulmonary complication rate of 16/183 (8.7%). Median (IQR [range]) length of hospital stay one year after implementation of ERAS+ also improved from 12 (9-15 [4-101]) to 9 (5.5-10.5 [3-81]) days. The ERAS+ pathway is applicable to patients undergoing elective major surgery and appears effective in reducing postoperative pulmonary complications.


Assuntos
Pneumopatias/prevenção & controle , Assistência Perioperatória/normas , Complicações Pós-Operatórias/prevenção & controle , Melhoria de Qualidade/organização & administração , Adulto , Idoso , Procedimentos Clínicos/organização & administração , Procedimentos Clínicos/normas , Inglaterra/epidemiologia , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Pneumopatias/diagnóstico , Pneumopatias/epidemiologia , Pneumopatias/etiologia , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Assistência Perioperatória/métodos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Prevalência , Avaliação de Programas e Projetos de Saúde
6.
Anaesthesia ; 70(11): 1274-80, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26348646

RESUMO

Ventilator-associated pneumonia is a common healthcare-associated infection with significant mortality, morbidity and healthcare cost, and rates have been proposed as a potential quality indicator. We examined ventilator-associated pneumonia rates as determined by different diagnostic scoring systems across four adult intensive care units in the North West of England. We also collected clinical opinions as to whether patients had ventilator-associated pneumonia, and whether patients were receiving antibiotics as treatment. Pooled ventilator-associated pneumonia rates were 36.3, 22.2, 15.2 and 1.1 per 1000 ventilator-bed days depending on the scoring system used. There was significant within-unit heterogeneity for ventilator-associated pneumonia rates calculated by the various scoring systems (all p < 0.001). Clinical opinion and antibiotic use did not correlate well with the scoring systems (k = 0.23 and k = 0.17, respectively). We therefore question whether the ventilator-associated pneumonia rate as measured by existing tools is either useful or desirable as a quality indicator.


Assuntos
Unidades de Terapia Intensiva/estatística & dados numéricos , Pneumonia Associada à Ventilação Mecânica/diagnóstico , Pneumonia Associada à Ventilação Mecânica/epidemiologia , Adulto , Inglaterra/epidemiologia , Mortalidade Hospitalar , Humanos , Tempo de Internação/estatística & dados numéricos , Estudos Prospectivos
7.
Anaesthesia ; 67(9): 1025-41, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22731935

RESUMO

Adult tracheostomy and laryngectomy airway emergencies are uncommon, but do lead to significant morbidity and mortality. The National Tracheostomy Safety Project incorporates key stakeholder groups with multi-disciplinary expertise in airway management. , the Intensive Care Society, the Royal College of Anaesthetists, ENT UK, the British Association of Oral and Maxillofacial Surgeons, the College of Emergency Medicine, the Resuscitation Council (UK) the Royal College of Nursing, the Royal College of Speech and Language Therapists, the Association of Chartered Physiotherapists in Respiratory Care and the National Patient Safety Agency. Resources and emergency algorithms were developed by consensus, taking into account existing guidelines, evidence and experiences. The stakeholder groups reviewed draft emergency algorithms and feedback was also received from open peer review. The final algorithms describe a universal approach to managing such emergencies and are designed to be followed by first responders. The project aims to improve the management of tracheostomy and laryngectomy critical incidents.


Assuntos
Manuseio das Vias Aéreas/normas , Serviços Médicos de Emergência/normas , Laringectomia/normas , Traqueostomia/normas , Adulto , Algoritmos , Criança , Remoção de Dispositivo , Desenho de Equipamento , Humanos , Laringectomia/instrumentação , Oxigenoterapia , Segurança do Paciente , Respiração , Sociedades Médicas , Sucção , Traqueostomia/instrumentação , Reino Unido
8.
Postgrad Med J ; 87(1032): 694-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21788232

RESUMO

BACKGROUND: The incidence and prevalence of obesity are increasing world wide. In the UK, obesity governmental strategy has primarily focused on prevention measures, with less focus on the demands of treating obese patients in hospital. Increasing service demand by obese patients coupled with a lack of adequate provision for care of these patients may lead to an increase in patient safety incidents. By classifying patient safety incidents associated with obesity reported to the National Patient Safety Agency, this report aims to identify areas for improvement in the quality and safety of care of the obese patient. METHODS: A search of the National Reporting and Learning System database was conducted for all incidents caused by or relating to obesity for the period 1 January 2005 to 31 August 2008. The keywords 'obesity', 'overweight', 'BMI' (body mass index), and 'bariatric' were used. The relevant free text fields of the resulting set of incidents were then searched for the terms designed to isolate incidents occurring in anaesthesia, critical care, and surgery. Reported incidents were analysed and subsequently categorised to identify incident themes. Levels of harm were also established. RESULTS: 555 patient safety incidents were identified; 388 met inclusion criteria for analysis. 148 incidents were related to assessment, diagnosis or treatment, 213 related to infrastructure and 27 related to staffing. The majority of incidents were classified as no or low harm. Three deaths were reported, all within the domain of anaesthesia. CONCLUSIONS: This report identifies that the majority of safety incidents associated with obesity were related to infrastructure, suggesting that there is inadequate provision in place for the care of obese patients. While levels of harm were mostly low, the occurrence of incidents resulting in severe harm or death highlights the specific dangers associated with the care of the obese patient. A global approach to improving the safety of care delivery for obese patients is recommended, including obesity specific training, management structures, care pathways, and equipment provisioning.Further planning and development of operation policies is needed to ensure the safe delivery of healthcare to obese patients in the future.


Assuntos
Bases de Dados Factuais/estatística & dados numéricos , Obesidade/complicações , Segurança do Paciente/estatística & dados numéricos , Guias de Prática Clínica como Assunto/normas , Gestão da Segurança/organização & administração , Atenção à Saúde/normas , Atenção à Saúde/estatística & dados numéricos , Humanos , Medicina Estatal , Reino Unido/epidemiologia
9.
Perioper Med (Lond) ; 10(1): 20, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34127080

RESUMO

BACKGROUND: Group education is increasing in popularity as a means of preparing patients for surgery. In recent years, these 'surgery schools' have evolved from primarily informing patients of what to expect before and after surgery, to providing support and encouragement for patients to 'prehabilitate' prior to surgery, through improving physical fitness, nutrition and emotional wellbeing. METHOD: A survey aimed at clinicians delivering surgery schools was employed to capture a national overview of activity to establish research and practice priorities in this area. The survey was circulated online via the Enhanced Recovery after Surgery UK Society and the Centre for Perioperative Care mailing lists as well as social media. RESULTS: There were 80 responses describing 28 active and 4 planned surgery schools across the UK and Ireland. Schools were designed and delivered by multidisciplinary teams, contained broadly similar content and were well attended. Most were funded by the National Health Service. The majority included aspects of prehabilitation most commonly the importance of physical fitness. Seventy five percent of teams collected patient outcome data, but less than half collected data to establish the clinical effectiveness of the school. Few describe explicit inclusion of evidence-based behavior change techniques, but collaboration and partnerships with community teams, gyms and local charities were considered important in supporting patients to make changes in health behaviors prior to surgery. CONCLUSION: It is recommended that teams work with patients when designing surgery schools and use evidence-based behavior change frameworks and techniques to inform their content. There is a need for high-quality research studies to determine the clinical effectiveness of this type of education intervention.

10.
Phytopathology ; 100(3): 279-89, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20128702

RESUMO

Features shared by host-specific phytophagous insects and biotrophic plant pathogens include gene-for-gene interactions and the ability to induce susceptibility in plants. The Hessian fly shows both. To protect against Hessian fly, grasses have H genes. Avirulent larvae die on H-gene-containing resistant plants but the cause of death is not known. Imaging techniques were used to examine epidermal cells at larval attack sites, comparing four resistant wheat genotypes (H6, H9, H13, and H26) to a susceptible genotype. Present in both resistant and susceptible plants attacked by larvae were small holes in the tangential cell wall, with the size of the holes (0.1 microm in diameter) matching that of the larval mandible. Absent from attacked resistant plants were signs of induced susceptibility, including nutritive tissue and ruptured cell walls. Present in attacked resistant plants were signs of induced resistance, including cell death and fortification of the cell wall. Both presumably limit larval access to food, because the larva feeds on the leaf surface by sucking up liquids released from ruptured cells. Resistance was associated with several subcellular responses, including elaboration of the endoplasmic reticulum-Golgi complex and associated vesicles. Similar responses are observed in plant resistance to fungi, suggesting that "vesicle-associated penetration resistance" also functions against insects.


Assuntos
Dípteros/fisiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Triticum/genética , Triticum/parasitologia , Animais , Genótipo , Larva/fisiologia , Doenças das Plantas/genética , Folhas de Planta/parasitologia , Folhas de Planta/ultraestrutura
11.
J Dairy Sci ; 93(7): 3365-76, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20630253

RESUMO

In this study, animal or dairy sciences faculty from doctoral/research universities were surveyed to clarify teaching performance expectations for the purpose of promotion and tenure of assistant professors. A survey tool including 15 evaluation criteria was available online and at the registration desk of the 2005 Joint Annual Meeting of the American Dairy Science Association and the American Society of Animal Science. The analyzed data set included 47 faculty (41 tenured and 6 tenure-track) with a substantial teaching responsibility from 27 different departments in 25 states. Four criteria were perceived as currently overemphasized: student evaluation of the instructor, student evaluation of the course, authoring peer-reviewed publications, and authoring an undergraduate textbook or book chapter. Nevertheless, more than 50% of respondents reported that these criteria should be used. One criterion emerged as being currently underemphasized: documentation of personal assessment of one's own teaching by preparing a portfolio. The lack of consensus for the remaining 10 items may have reflected substantial differences in institutional practices. The significance of overemphasis or underemphasis of certain criteria varied substantially depending on the respondent's perceived institutional mission. When asked about recognition within their department, 68% of respondents indicated that efforts in teaching improvement were properly rewarded. Respondents doubted the meaningfulness and appropriateness of student ratings tools as currently used. Results also suggested that animal and dairy science faculty placed a higher value on criteria recognizing excellence in teaching based on intradepartmental recognition (e.g., interactions with close-up peers and students) rather than recognition within a broader community of scholars as evidenced by authorship or success in generating funding for teaching. Proposed improvements in the evaluation of teaching for promotion and tenure include 1) providing tenure-track faculty with written guidelines at the time of hiring; 2) ensuring that student ratings tools are reliable and valid; 3) carefully mentoring new faculty within the departmental and institutional culture; and 4) encouraging self-reflection and documentation of attempts to address pedagogical issues in one's own teaching. Educational leaders in doctoral/research universities should promote changes to enhance teaching performance of future faculty graduating from their institutions.


Assuntos
Indústria de Laticínios/educação , Docentes/normas , Ensino/normas , Universidades/normas , Indústria de Laticínios/normas , Demografia , Estudos de Avaliação como Assunto , Humanos , Pesquisa , Recompensa
12.
Anal Chem ; 81(15): 6186-94, 2009 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20337395

RESUMO

A library of molecular analogues to the selective displacer, N'1'-(4-methylquinolin-2-yl)ethane-1,2-diamine dinitrate, was employed to study the effects of changes in displacer chemistry on their efficacy for selective separations. High throughput screens were carried out using a robotic liquid handling system to examine the ability of these compounds to selectively displace proteins in batch adsorption systems. Experiments were conducted using the model protein pairs ribonuclease A/alpha-chymotrypsinogen A and cytochrome C/lysozyme on a strong cation exchanger. Selectivity pathway and DC-50 plots were constructed from the analogue screen data, and results indicated that minor changes in the molecular design of the displacer can have a significant impact on the separation behavior. Specifically, charge density and spacing of resin and protein interaction moieties were found to be important. The screen also identified a new displacer, 4-methyl-2-piperazin-1-yl-quinoline, which produced a more selective displacement than previously reported with the original compound. A steric mass action dynamic affinity plot was constructed to validate that this new displacer was acting as a chemically selective, rather than a steric mass action selective displacer. Finally, saturation transfer difference NMR experiments were conducted to examine protein-displacer interactions with these displacers and protein pairs. These results demonstrate how subtle changes in displacer design can be employed to fine-tune the separation performance of chemically selective displacers.


Assuntos
Cromatografia de Afinidade , Cromatografia por Troca Iônica , Quimotripsinogênio/isolamento & purificação , Citocromos c/isolamento & purificação , Muramidase/isolamento & purificação , Ribonuclease Pancreático/isolamento & purificação , Animais , Quimotripsinogênio/metabolismo , Citocromos c/metabolismo , Enzimas Imobilizadas , Espectroscopia de Ressonância Magnética , Muramidase/metabolismo , Ribonuclease Pancreático/metabolismo
13.
Mol Ecol ; 18(18): 3792-802, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19732338

RESUMO

Reduced genetic diversity can result in short-term decreases in fitness and reduced adaptive potential, which may lead to an increased extinction risk. Therefore, maintaining genetic variation is important for the short- and long-term success of reintroduced populations. Here, we evaluate how founder group size and variance in male reproductive success influence the long-term maintenance of genetic diversity after reintroduction. We used microsatellite data to quantify the loss of heterozygosity and allelic diversity in the founder groups from three reintroductions of tuatara (Sphenodon), the sole living representatives of the reptilian order Rhynchocephalia. We then estimated the maintenance of genetic diversity over 400 years (approximately 10 generations) using population viability analyses. Reproduction of tuatara is highly skewed, with as few as 30% of males mating across years. Predicted losses of heterozygosity over 10 generations were low (1-14%), and populations founded with more animals retained a greater proportion of the heterozygosity and allelic diversity of their source populations and founder groups. Greater male reproductive skew led to greater predicted losses of genetic diversity over 10 generations, but only accelerated the loss of genetic diversity at small population size (<250 animals). A reduction in reproductive skew at low density may facilitate the maintenance of genetic diversity in small reintroduced populations. If reproductive skew is high and density-independent, larger founder groups could be released to achieve genetic goals for management.


Assuntos
Efeito Fundador , Variação Genética , Genética Populacional , Lagartos/genética , Alelos , Animais , Conservação dos Recursos Naturais , Perda de Heterozigosidade , Masculino , Repetições de Microssatélites , Modelos Genéticos , Nova Zelândia , Reprodução/genética , Análise de Sequência de DNA
15.
J Am Chem Soc ; 130(50): 17029-37, 2008 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-19053488

RESUMO

One of the major impediments to the implementation of displacement chromatography for the purification of biomolecules is the need to collect fractions from the column effluent for time-consuming offline analysis. The ability to employ direct online monitoring of displacement chromatography would have significant implications for applications ranging from analytical to preparative bioseparations. To this end, a set of novel fluorescent displacers were rationally designed using known chemically selective displacers as a template. Fluorescent cores were functionalized with different charge moieties, creating a homologous library of displacers. These compounds were then tested on two protein pairs, alpha-chymotrypsinogen A/ribonuclease A and cytochrome c/lysozyme, using batch and column displacement experiments. Of the synthesized displacers, two were found to be highly selective while one was determined to be a high-affinity displacer. Column displacements using one of the selective displacers yielded complete separation of both protein pairs while facilitating direct online detection using UV and fluorescence detection. Saturation transfer difference NMR was also carried out to investigate the binding of the fluorescent displacers to proteins. The results indicated a selective binding between the selective displacers and alpha-chymotrypsinogen A, while no binding was observed for ribonuclease A, confirming that protein-displacer binding is responsible for the selectivity in these systems. This work demonstrates the utility of fluorescent displacers to enable online monitoring of displacer breakthroughs while also acting as efficient displacers for protein purification.


Assuntos
Corantes Fluorescentes/análise , Corantes Fluorescentes/síntese química , Internet , Cromatografia , Quimotripsina/metabolismo , Corantes Fluorescentes/química , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Ribonuclease Pancreático/metabolismo
16.
Mol Ecol ; 17(21): 4630-41, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19140986

RESUMO

Anthropogenic habitat fragmentation--ubiquitous in modern ecosystems--has strong impacts on gene flow and genetic population structure. Reptiles may be particularly susceptible to the effects of fragmentation because of their extreme sensitivity to environmental conditions and limited dispersal. We investigate fine-scale spatial genetic structure, individual relatedness, and sex-biased dispersal in a large population of a long-lived reptile (tuatara, Sphenodon punctatus) on a recently fragmented island. We genotyped individuals from remnant forest, regenerating forest, and grassland pasture sites at seven microsatellite loci and found significant genetic structuring (R(ST)=0.012) across small distances (<500 m). Isolation by distance was not evident, but rather, genetic distance was weakly correlated with habitat similarity. Only individuals in forest fragments were correctly assignable to their site of origin, and individual pairwise relatedness in one fragment was significantly higher than expected. We did not detect sex-biased dispersal, but natural dispersal patterns may be confounded by fragmentation. Assignment tests showed that reforestation appears to have provided refuges for tuatara from disturbed areas. Our results suggest that fine-scale genetic structuring is driven by recent habitat modification and compounded by the sedentary lifestyle of these long-lived reptiles. Extreme longevity, large population size, simple social structure and random dispersal are not strong enough to counteract the genetic structure caused by a sedentary lifestyle. We suspect that fine-scale spatial genetic structuring could occur in any sedentary species with limited dispersal, making them more susceptible to the effects of fragmentation.


Assuntos
Ecossistema , Genética Populacional , Répteis/genética , Alelos , Animais , Conservação dos Recursos Naturais , Feminino , Fluxo Gênico , Variação Genética , Genótipo , Geografia , Masculino , Repetições de Microssatélites , Densidade Demográfica , Dinâmica Populacional , Fatores Sexuais
20.
Biomicrofluidics ; 11(1): 014110, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28191268

RESUMO

This paper reports on the use of a digital microfluidic platform to perform multiplex automated genetic engineering (MAGE) cycles on droplets containing Escherichia coli cells. Bioactivated magnetic beads were employed for cell binding, washing, and media exchange in the preparation of electrocompetent cells in the electrowetting-on-dieletric (EWoD) platform. On-cartridge electroporation was used to deliver oligonucleotides into the cells. In addition to the optimization of a magnetic bead-based benchtop protocol for generating and transforming electrocompetent E. coli cells, we report on the implementation of this protocol in a fully automated digital microfluidic platform. Bead-based media exchange and electroporation pulse conditions were optimized on benchtop for transformation frequency to provide initial parameters for microfluidic device trials. Benchtop experiments comparing electrotransformation of free and bead-bound cells are presented. Our results suggest that dielectric shielding intrinsic to bead-bound cells significantly reduces electroporation field exposure efficiency. However, high transformation frequency can be maintained in the presence of magnetic beads through the application of more intense electroporation pulses. As a proof of concept, MAGE cycles were successfully performed on a commercial EWoD cartridge using variations of the optimal magnetic bead-based preparation procedure and pulse conditions determined by the benchtop results. Transformation frequencies up to 22% were achieved on benchtop; this frequency was matched within 1% (21%) by MAGE cycles on the microfluidic device. However, typical frequencies on the device remain lower, averaging 9% with a standard deviation of 9%. The presented results demonstrate the potential of digital microfluidics to perform complex and automated genetic engineering protocols.

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