Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros

Base de dados
País como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Nano Lett ; 20(7): 5383-5390, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32463679

RESUMO

Single cell manipulation is important in biosensing, biorobotics, and quantitative cell analysis. Although microbeads, droplets, and microrobots have been developed previously, it is still challenging to simultaneously excise, capture, and manipulate single cells in a biocompatible manner. Here, we describe untethered single cell grippers, that can be remotely guided and actuated on-demand to actively capture or excise individual or few cells. We describe a novel molding method to micropattern a thermally responsive wax layer for biocompatible motion actuation. The multifingered grippers derive their energy from the triggered release of residual differential stress in bilayer hinges composed of silicon oxides. A magnetic layer enables remote guidance through narrow conduits and fixed tissue sections ex vivo. Our results provide an important advance in high-throughput single cell scale biopsy tools important to lab-on-a-chip devices, microrobotics, and minimally invasive surgery.


Assuntos
Robótica , Biópsia , Magnetismo , Movimento (Física) , Dióxido de Silício
2.
Ann Bot ; 124(4): 591-604, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-30596965

RESUMO

BACKGROUND AND AIMS: Germplasm with diverse, agronomically relevant traits forms the foundation of a successful plant breeding programme. Since 1993, the United Nations has been advocating the implementation of the Convention on Biological Diversity (CBD) and the subsequent 2002 Bonn Guidelines as international best practice on germplasm collection and use. In 2006, a European team made an expedition to Asia to collect wild germplasm of Miscanthus, a C4 perennial rhizomatous grass, for breeding an environmentally adaptable, resilient and high-yielding bioenergy crop. We outline general aspects of germplasm collection, conservation, breeding and biomass production evaluation while following the CBD's guidelines, respecting biodiversity and conservation needs, and the ethical use of genetic resources. METHODS: Effective protocols, quarantine, methods for collecting seed and rhizomes, and a genebank for conservation were established. Versatile informatics and database architecture were used to assist in selection, flowering synchronization, crossing, evaluation, phenotyping and data integration. Approaches were formulated to comply with the CBD guidelines. KEY RESULTS: A total of 303 accessions of M. sinensis, M. sacchariflorus and M. floridulus were collected from 158 geographically and environmentally diverse locations. These species were shown to accumulate different amounts of aerial biomass due to combinations of stem count, height and thickness. Progeny from one interspecies cross accumulated more biomass in early trials and has shown double the yield performance in years 3-4 compared with the existing commercial cultivar M. × giganteus. An example of an F1 hybrid has already demonstrated the long-term potential of exploiting this collection for a breeding programme. CONCLUSIONS: By conforming to the CBD principles, the authors' international collaboration provides a practical example of implementing the CBD. The collection widened the genetic diversity of Miscanthus available to allow for breeding of novel hybrids that exhibit more diverse traits to increase yield and resilience for growth on marginal land and in climate-challenged environments.


Assuntos
Biodiversidade , Poaceae , Ásia , Europa (Continente) , Nações Unidas
3.
Microbiology (Reading) ; 163(3): 289-296, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28086069

RESUMO

Working with genetic resources and associated data requires greater attention since the Nagoya Protocol on Access and Benefit Sharing (ABS) came into force in October 2014. Biologists must ensure that they have legal clarity in how they can and cannot use the genetic resources on which they carry out research. Not only must they work within the spirit in the Convention on Biological Diversity (https://www.cbd.int/convention/articles/default.shtml?a=cbd-02) but also they may have regulatory requirements to meet. Although the Nagoya Protocol was negotiated and agreed globally, it is the responsibility of each country that ratifies it to introduce their individual implementing procedures and practices. Many countries in Europe, such as the UK, have chosen not to put access controls in place at this time, but others already have laws enacted providing ABS measures under the Convention on Biological Diversity or specifically to implement the Nagoya Protocol. Access legislation is in place in many countries and information on this can be found at the ABS Clearing House (https://absch.cbd.int/). For example, Brazil, although not a Party to the Nagoya Protocol at the time of writing, has Law 13.123 which entered into force on 17 November 2015, regulated by Decree 8.772 which was published on 11 May 2016. In this case, export of Brazilian genetic resources is not allowed unless the collector is registered in the National System for Genetic Heritage and Associated Traditional Knowledge Management (SisGen). The process entails that a foreign scientist must first of all be registered working with someone in Brazil and have authorization to collect. The enactment of European Union Regulation po. 511/2014 implements Nagoya Protocol elements that govern compliance measures for users and offers the opportunity to demonstrate due diligence in sourcing their organisms by selecting from holdings of 'registered collections'. The UK has introduced a Statutory Instrument that puts in place enforcement measures within the UK to implement this European Union Regulation; this is regulated by Regulatory Delivery, Department for Business, Energy and Industrial Strategies. Scientific communities, including the private sector, individual institutions and organizations, have begun to design policy and best practices for compliance. Microbiologists and culture collections alike need to be aware of the legislation of the source country of the materials they use and put in place best practices for compliance; such best practice has been drafted by the Microbial Resource Research Infrastructure, and other research communities such as the Consortium of European Taxonomic Facilities, the Global Genome Biodiversity Network and the International Organisation for Biological Control have published best practice and/or codes of conduct to ensure legitimate exchange and use of genetic resources.


Assuntos
Pesquisa em Genética/legislação & jurisprudência , Troca de Informação em Saúde/legislação & jurisprudência , Cooperação Internacional , Alocação de Recursos/legislação & jurisprudência , Conservação dos Recursos Naturais
4.
J Vasc Surg Venous Lymphat Disord ; : 101936, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945363

RESUMO

INTRODUCTION: We evaluated the impact of completion intraoperative venography on clinical outcomes for axillosubclavian vein (AxSCV) thrombosis due to venous thoracic outlet syndrome (vTOS). METHODS: We performed a retrospective, single-center review of all patients with vTOS treated with First Rib Resection and intraoperative venography from 2011 - 2023. We reviewed intraoperative venographic films to classify findings, collected demographics, clinical and perioperative variables, and clinical outcomes. Primary endpoints were symptomatic relief and primary patency at 3 months and 1 year. Secondary endpoints were time free from symptoms, reintervention rate, perioperative complications, and mortality. RESULTS: Fifty-one AxSCVs (49 patients, mean age of 31.3 ± 12.6, 52.9% female) were treated for vTOS with first rib resection and external venolysis followed by completion intraoperative venography with a mean follow up of 15.5 ± 13.5 months. Prior to FRR, 32 underwent catheter-directed thrombolysis (62.7%). Completion intraoperative venography identified 16 patients with No Stenosis (Group 1, 31.3%), 17 with No Stenosis after Angioplasty (Group 2, 33.3%), 10 with Residual Stenosis after Angioplasty (Group 3, 19.7%), and 8 with Complete Occlusion (Group 4, 15.7%). The overall symptomatic relief was 44 of 51 (86.3%) and did not differ between venographic classifications (Group 1: 14 of 16, Group 2: 13 of 17, Group 3: 10 of 10, and Group 4: 7 of 8; Log-Rank Test, p = 0.5). The overall 3-month and 1-year primary patency was 42 of 43 (97.7%) and 32 of 33 (97.0%), respectively (Group 1: 16 of 16 and 9 of 9; Group 2: 16 of 17 and 12 of 13; Group 3: 10 of 10, 5 of 5; Group 4: primary patency not obtained). There was one asymptomatic re-thrombosis that resolved with anticoagulation, and three patients underwent reintervention with venous angioplasty for significant symptom recurrence an average 2.89 ± 1.7 months after FRR. CONCLUSION: Our single-center retrospective study demonstrates that FRR with completion intraoperative venography has excellent symptomatic relief, short- and mid-term patency despite residual venous stenosis and complete occlusion. While completion intraoperative venographic classification did not correlate with adverse outcomes, this protocol yielded excellent results and provides important clinical data for postoperative management. Our results also support a conservative approach to AxSCV occlusion identified after FRR.

5.
Gen Thorac Cardiovasc Surg ; 71(12): 723-729, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37310563

RESUMO

OBJECTIVE: Although an ultrasonic harmonic scalpel (HS) has been used to harvest the internal mammary artery (IMA) for coronary artery bypass grafting, the benefits and risks compared to conventional electrocautery (EC) are not clear. We aimed to compare the outcomes of HS versus EC for IMA harvesting. METHODS: An electronic search was performed to identify all relevant studies. Baseline characteristics, perioperative variables, and clinical outcomes were extracted and pooled for meta-analysis. RESULTS: This meta-analysis included 12 studies. Pooled analyses demonstrated that both groups had comparable preoperative baseline characteristics including age, gender, and left ventricular ejection fraction. HS included more diabetic patients [33% (95% CI 30, 35) vs. 27% (23, 31), p = 0.01]. Harvest time for unilateral IMA was significantly longer with HS than EC [39 (31, 47) minutes vs. 25 (17, 33) minutes, p < 0.01]. However, the rate of pedicled unilateral IMA was significantly higher for EC compared with HS [20% (17, 24) vs. 8% (7, 9), p < 0.01]. The rate of intact endothelium was significantly higher with HS than EC [95% (88, 98) vs. 81% (68, 89), p < 0.01). There was no significant difference in postoperative outcomes including bleeding [3% (2, 4)], sternal infection [3% (2, 4)], and operative/30-day mortality [3% (2, 4)]. CONCLUSIONS: HS required longer IMA harvest times which could be partially attributed to a higher skeletonization rate in this category. HS may cause less endothelial injury than EC; however, no significant differences in postoperative outcomes were seen between the groups.


Assuntos
Artéria Torácica Interna , Ultrassom , Humanos , Volume Sistólico , Função Ventricular Esquerda , Eletrocoagulação/efeitos adversos
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa