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1.
BMC Nurs ; 23(1): 408, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886722

RESUMO

This letter to the editor is a commentary on the scoping review by Skudlik et al. (2023) on the relocation of older people to nursing homes in Germany. In this commentary, we question certain methodological decisions that, in our view, particularly affect transferability of the results and give a partial picture of the phenomena studied by limiting the inclusion to German studies. We also have questions about the choice of knowledge synthesis method and why the concept of "nursing home" was not defined. We hope that this letter will open a constructive scientific discussion on an important topic that is understudied as the world's population ages.

2.
Small ; 18(15): e2107381, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35218608

RESUMO

Using DNA as a durable, high-density storage medium with eternal format relevance can address a future data storage deficiency. The proposed storage format incorporates dehydrated particle spots on glass, at a theoretical capacity of more than 20 TB per spot, which can be efficiently retrieved without significant loss of DNA. The authors measure the rapid decay of dried DNA at room temperature and present the synthesis of encapsulated DNA in silica nanoparticles as a possible solution. In this form, the protected DNA can be readily applied to digital microfluidics (DMF) used to handle retrieval operations amenable to full automation. A storage architecture is demonstrated, which can increase the storage capacity of today's archival storage systems by more than three orders of magnitude: A DNA library containing 7373 unique sequences is encapsulated and stored under accelerated aging conditions (4 days at 70 °C, 50% RH) corresponding to 116 years at room temperature and the stored information is successfully recovered.


Assuntos
DNA , Microfluídica , Vidro , Armazenamento e Recuperação da Informação , Temperatura
3.
Langmuir ; 38(37): 11191-11198, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36083165

RESUMO

A core-shell strategy was developed to protect synthetic DNA in organosilica particles encompassing dithiol linkages allowing for a DNA loading of 1.1 wt %. DNA stability tests involving bleach as an oxidant showed that following the procedure DNA was sandwiched between core particles of ca. 450 nm size and a protective outer layer, separating the DNA from the environment. Rapid aging tests at 60 °C and 50% relative humidity revealed that the DNA protected within this material was significantly more stable than nonprotected DNA, with an expected ambient temperature half-life of over 60 years. Still, and due to the presence of the dithiol linkages in the backbone of the organosilica material, the particles degraded in the presence of reducing agents (TCEP and glutathione) and disintegrated within several days in a simulated compost environment, which was employed to test the biodegradability of the material. This is in contrast to DNA encapsulated following state of the art procedures in pure SiO2 particles, which do not biodegrade in the investigated timeframes and conditions. The results show that synthetic DNA protected within dithiol comprising organosilica particles presents a strategy to store digital data at a high storage capacity for long time frames in a fully biodegradable format.


Assuntos
Nanopartículas , Dióxido de Silício , DNA/genética , Glutationa , Oxidantes , Substâncias Redutoras , Tolueno/análogos & derivados
4.
Angew Chem Int Ed Engl ; 58(11): 3562-3565, 2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30706627

RESUMO

While the majority of reported paired electrochemical reactions involve carefully matched cathodic and anodic reactions, the precise matching of half reactions in an electrolysis cell is not generally necessary. During a constant current electrolysis almost any oxidation and reduction reaction can be paired, and in the presented work we capitalize on this observation by examining the coupling of anodic oxidation reactions with the production of hydrogen gas for use as a reagent in remote, Pd-catalyzed hydrogenation and hydrogenolysis reactions. To this end, an alcohol oxidation, an oxidative condensation, intramolecular anodic olefin coupling reactions, an amide oxidation, and a mediated oxidation were all shown to be compatible with the generation and use of hydrogen gas at the cathode. This pairing of an electrolysis reaction with the production of a chemical reagent or substrate has the potential to greatly expand the use of more energy efficient paired electrochemical reactions.

5.
J Am Chem Soc ; 138(46): 15110-15113, 2016 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-27933880

RESUMO

In electrochemical processes, an oxidation half-reaction is always paired with a reduction half-reaction. Although systems for reactions such as the reduction of CO2 can be coupled to water oxidation to produce O2 at the anode, large-scale O2 production is of limited value. One may replace a low-value half-reaction with a compatible half-reaction that can produce a valuable chemical compound and operate at a lower potential. In doing so, both the anodic and cathodic half-reactions yield desirable products with a decreased energy demand. Here we demonstrate a paired electrolysis in the case of the oxidative condensation of syringaldehyde and o-phenylenediamine to give 2-(3,5-dimethoxy-4-hydroxyphenyl)benzimidazole coupled with the reduction of CO2 to CO mediated by molecular electrocatalysts. We also present general principles for evaluating current-voltage characteristics and power demands in paired electrolyzers.

6.
Support Care Cancer ; 24(6): 2549-56, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26694719

RESUMO

PURPOSE: When dealing with health issues, older cancer patients are likely to visit emergency rooms (ER), which are known to expose these patients to the risk of adverse outcomes. Little is known about the profile and reasons for such visits. The aim of this study is (1) to describe the profile of elderly cancer patients aged 70 years and older who visited the ER of a regional hospital in Québec, Canada, and (2) to explain the medical reasons and factors determining such visits from the patients' perspective. METHODS: A concurrent mixed method design was used. Descriptive analysis of administrative databases was conducted to describe the socio-demographic, clinical, and service utilization profile of 792 cancer patients aged 70 years and older. Content analysis of 11 semi-structured interviews of a sub-sample was subsequently performed to better understand the experience and meaning these patients attribute to this health behaviour. RESULTS: The sample of 792 older cancer patients made a total of 1572 ER visits. Most visits occurred during the daytime. More than half (53 %) of the patients were discharged, and close to 40 % were hospitalized. The most frequent reasons for consulting were respiratory (15.8 %), digestive (13.4 %), neurological (8.3 %), fever or infection-related (8.3 %), and cardiovascular (8.2 %). Content analysis of the qualitative data suggested that patients made ER visits mostly when other cancer care services were unavailable or because of a serious life-threatening health condition. CONCLUSIONS: The study suggests areas of improvement to prevent ER visits when health issues can be addressed by other care services.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Neoplasias/psicologia , Neoplasias/terapia , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Neoplasias/epidemiologia , Quebeque/epidemiologia , Fatores Sociológicos
7.
J Org Chem ; 80(24): 11953-62, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26544912

RESUMO

Either aldehyde or cinnamyl ether products can be selectively extracted from raw sawdust by controlling the temperature and pressure of a solvolysis reaction. These materials have been used as platform chemicals for the synthesis of 15 different synthetic substrates. The conversion of the initial sawdust-derived materials into electron-rich aryl substrates often requires the use of oxidation and reduction chemistry, and the role electrochemistry can play as a sustainable method for these transformations has been defined.

8.
Beilstein J Org Chem ; 11: 280-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25815081

RESUMO

The combination of visible light, photovoltaics, and electrochemistry provides a convenient, inexpensive platform for conducting a wide variety of sustainable oxidation reactions. The approach presented in this article is compatible with both direct and indirect oxidation reactions, avoids the need for a stoichiometric oxidant, and leads to hydrogen gas as the only byproduct from the corresponding reduction reaction.

9.
Ann Surg Oncol ; 21(10): 3261-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25099655

RESUMO

PURPOSE: The purpose of the NBRST study is to compare a multigene classifier to conventional immunohistochemistry (IHC)/fluorescence in situ hybridization (FISH) subtyping to predict chemosensitivity as defined by pathological complete response (pCR) or endocrine sensitivity as defined by partial response. METHODS: The study includes women with histologically proven breast cancer, who will receive neoadjuvant chemotherapy (NCT) or neoadjuvant endocrine therapy. BluePrint in combination with MammaPrint classifies patients into four molecular subgroups: Luminal A, Luminal B, HER2, and Basal. RESULTS: A total of 426 patients had definitive surgery. Thirty-seven of 211 (18 %) IHC/FISH hormone receptor (HR)+/HER2- patients were reclassified by Blueprint as Basal (n = 35) or HER2 (n = 2). Fifty-three of 123 (43 %) IHC/FISH HER2+ patients were reclassified as Luminal (n = 36) or Basal (n = 17). Four of 92 (4 %) IHC/FISH triple-negative (TN) patients were reclassified as Luminal (n = 2) or HER2 (n = 2). NCT pCR rates were 2 % in Luminal A and 7 % Luminal B patients versus 10 % pCR in IHC/FISH HR+/HER2- patients. The NCT pCR rate was 53 % in BluePrint HER2 patients. This is significantly superior (p = 0.047) to the pCR rate in IHC/FISH HER2+ patients (38 %). The pCR rate of 36 of 75 IHC/FISH HER2+/HR+ patients reclassified as BPLuminal is 3 %. NCT pCR for BluePrint Basal patients was 49 of 140 (35 %), comparable to the 34 of 92 pCR rate (37 %) in IHC/FISH TN patients. CONCLUSIONS: BluePrint molecular subtyping reclassifies 22 % (94/426) of tumors, reassigning more responsive patients to the HER2 and Basal categories while reassigning less responsive patients to the Luminal category. These findings suggest that compared with IHC/FISH, BluePrint more accurately identifies patients likely to respond (or not respond) to NCT.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Terapia Neoadjuvante , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Sistema de Registros , Taxa de Sobrevida , Adulto Jovem
10.
Langmuir ; 30(8): 2280-6, 2014 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-24499393

RESUMO

Oxidation reactions are powerful tools for synthesis because they allow for the functionalization of molecules. Here, we present a general method for conducting these reactions on a microelectrode array in a site-selective fashion. The reactions are run as a competition between generation of a chemical oxidant at the electrodes in the array and reduction of the oxidant by a "confining agent" in the solution above the array. The "confining agent" does not need to be more reactive than the substrate fixed to the surface of the array. In many cases, the same substrate placed on the surface of the array can also be used in solution as the confining agent.

11.
J Hazard Mater ; 473: 134545, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38761760

RESUMO

Printed circuit boards (PCBs) make up a substantial amount of electronic waste (e-waste) generated annually. Waste PCBs contain high quantities of copper and gold in comparison to natural ores. As such, "urban mining" of waste PCBs to recover these metals is of commercial interest. In this work, we used life cycle assessment to compare the environmental impact of four copper and gold recovery processes. We evaluated pyrometallurgy, chemical leaching, and bioleaching, as well as a hybrid leaching process that uses bioleaching to recover copper and chemical leaching to recover gold. Furthermore, we considered differences in environmental impact based on differences in electricity sources. If electricity comes from fossil fuels, the pyrometallurgical process results in the lowest environmental impact in all impact categories studied. If electricity comes from carbon-free sources, the pyrometallurgical process results in the lowest environmental impact in all categories studied except global warming, where the hybrid leaching process results in the lowest impact. In all cases, metal recovery from waste PCBs leads to lower environmental impact than primary metal production. Our goal is to guide e-waste recyclers towards more environmentally sustainable metal recovery processes and to provide knowledge gaps in the field to guide future research.

12.
ACS Synth Biol ; 12(11): 3156-3169, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37935025

RESUMO

Synthetic Biology has overcome many of the early challenges facing the field and is entering a systems era characterized by adoption of Design-Build-Test-Learn (DBTL) approaches. The need for automation and standardization to enable reproducible, scalable, and translatable research has become increasingly accepted in recent years, and many of the hardware and software tools needed to address these challenges are now in place or under development. However, the lack of connectivity between DBTL modules and barriers to access and adoption remain significant challenges to realizing the full potential of lab automation. In this review, we characterize and classify the state of automation in synthetic biology with a focus on the physical automation of experimental workflows. Though fully autonomous scientific discovery is likely a long way off, impressive progress has been made toward automating critical elements of experimentation by combining intelligent hardware and software tools. It is worth questioning whether total automation that removes humans entirely from the loop should be the ultimate goal, and considerations for appropriate automation versus total automation are discussed in this light while emphasizing areas where further development is needed in both contexts.


Assuntos
Automação Laboratorial , Biologia Sintética , Humanos , Automação , Software , Padrões de Referência , Projetos de Pesquisa
13.
ACS Synth Biol ; 12(6): 1716-1726, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-37192389

RESUMO

Novel enzymatic methods are poised to become the dominant processes for de novo synthesis of DNA, promising functional, economic, and environmental advantages over the longstanding approach of phosphoramidite synthesis. Before this can occur, however, enzymatic synthesis methods must be parallelized to enable production of multiple DNA sequences simultaneously. As a means to this parallelization, we report a polymerase-nucleotide conjugate that is cleaved using electrochemical oxidation on a microelectrode array. The developed conjugate maintains polymerase activity toward surface-bound substrates with single-base control and detaches from the surface at mild oxidative voltages, leaving an extendable oligonucleotide behind. Our approach readies the way for enzymatic DNA synthesis on the scale necessary for DNA-intensive applications such as DNA data storage or gene synthesis.


Assuntos
DNA Nucleotidilexotransferase , Nucleotídeos , DNA Nucleotidilexotransferase/genética , DNA , Oligonucleotídeos , Sequência de Bases
14.
Proc Conf Assoc Comput Linguist Meet ; 2023: 10520-10542, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38689884

RESUMO

Summarization models often generate text that is poorly calibrated to quality metrics because they are trained to maximize the likelihood of a single reference (MLE). To address this, recent work has added a calibration step, which exposes a model to its own ranked outputs to improve relevance or, in a separate line of work, contrasts positive and negative sets to improve faithfulness. While effective, much of this work has focused on how to generate and optimize these sets. Less is known about why one setup is more effective than another. In this work, we uncover the underlying characteristics of effective sets. For each training instance, we form a large, diverse pool of candidates and systematically vary the subsets used for calibration fine-tuning. Each selection strategy targets distinct aspects of the sets, such as lexical diversity or the size of the gap between positive and negatives. On three diverse scientific long-form summarization datasets (spanning biomedical, clinical, and chemical domains), we find, among others, that faithfulness calibration is optimal when the negative sets are extractive and more likely to be generated, whereas for relevance calibration, the metric margin between candidates should be maximized and surprise-the disagreement between model and metric defined candidate rankings-minimized. Code to create, select, and optimize calibration sets is available at https://github.com/griff4692/calibrating-summaries.

15.
Nat Nanotechnol ; 18(8): 912-921, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37142708

RESUMO

DNA has emerged as an attractive medium for archival data storage due to its durability and high information density. Scalable parallel random access to information is a desirable property of any storage system. For DNA-based storage systems, however, this still needs to be robustly established. Here we report on a thermoconfined polymerase chain reaction, which enables multiplexed, repeated random access to compartmentalized DNA files. The strategy is based on localizing biotin-functionalized oligonucleotides inside thermoresponsive, semipermeable microcapsules. At low temperatures, microcapsules are permeable to enzymes, primers and amplified products, whereas at high temperatures, membrane collapse prevents molecular crosstalk during amplification. Our data show that the platform outperforms non-compartmentalized DNA storage compared with repeated random access and reduces amplification bias tenfold during multiplex polymerase chain reaction. Using fluorescent sorting, we also demonstrate sample pooling and data retrieval by microcapsule barcoding. Therefore, the thermoresponsive microcapsule technology offers a scalable, sequence-agnostic approach for repeated random access to archival DNA files.


Assuntos
DNA , Armazenamento e Recuperação da Informação , Cápsulas , DNA/genética , Oligonucleotídeos , Sequenciamento de Nucleotídeos em Larga Escala
16.
Ann Surg Oncol ; 19(10): 3257-63, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22965266

RESUMO

PURPOSE: To compare breast cancer subtyping with the three centrally assessed microarray-based assays BluePrint, MammaPrint, and TargetPrint with locally assessed clinical subtyping using immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). METHODS: BluePrint, MammaPrint, and TargetPrint were all performed on fresh tumor samples. Microarray analysis was performed at Agendia Laboratories, blinded for clinical and pathological data. IHC/FISH assessments were performed according to local practice at each institution; estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) assessments were performed on 132 samples, and Ki-67 on 79 samples. RESULTS: The concordance between BluePrint and IHC/FISH subtyping was 94 % for the Luminal-type, 95 % for the HER2-type, and 94 % for the Basal-type subgroups. The concordance of BluePrint with subtyping using mRNA single gene readout (TargetPrint) was 96 % for the Luminal-type, 97 % for the HER2-type, and 98 % for the Basal-type subgroups. The concordance for substratification into Luminal A and B using MammaPrint and Ki-67 was 68 %. The concordance between TargetPrint and IHC/FISH was 97 % for ER, 80 % for PR, and 95 % for HER2. CONCLUSIONS: The implementation of multigene assays such as TargetPrint, BluePrint, and MammaPrint may improve the clinical management of breast cancer patients. High discordance between Luminal A and B substratification based on MammaPrint versus locally assessed Ki-67 or grade indicates that chemotherapy decisions should not be based on the basis of Ki-67 readout or tumor grade alone. TargetPrint serves as a second opinion for those local pathology settings where high-quality standardization is harder to maintain.


Assuntos
Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/classificação , Perfilação da Expressão Gênica , RNA Mensageiro/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Técnicas Imunoenzimáticas , Hibridização in Situ Fluorescente , Antígeno Ki-67/metabolismo , Análise em Microsséries , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Taxa de Sobrevida
17.
Sci Total Environ ; 821: 152790, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35007574

RESUMO

Affordably tracking the transmission of respiratory infectious diseases in urban transport infrastructures can inform individuals about potential exposure to diseases and guide public policymakers to prepare timely responses based on geographical transmission in different areas in the city. Towards that end, we designed and tested a method to detect SARS-CoV-2 RNA in the air filters of public buses, revealing that air filters could be used as passive fabric sensors for the detection of viral presence. We placed and retrieved filters in the existing HVAC systems of public buses to test for the presence of trapped SARS-CoV-2 RNA using phenol-chloroform extraction and RT-qPCR. SARS-CoV-2 RNA was detected in 14% (5/37) of public bus filters tested in Seattle, Washington, from August 2020 to March 2021. These results indicate that this sensing system is feasible and that, if scaled, this method could provide a unique lens into the geographically relevant transmission of SARS-CoV-2 through public transit rider vectors, pooling samples of riders over time in a passive manner without installing any additional systems on transit vehicles.


Assuntos
Veículos Automotores , RNA Viral/isolamento & purificação , SARS-CoV-2 , Meios de Transporte , COVID-19 , Monitoramento Ambiental , Humanos , SARS-CoV-2/isolamento & purificação , Washington
18.
Chem Commun (Camb) ; 58(19): 3174-3177, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35171192

RESUMO

The resilience of ancient DNA (aDNA) in bone gives rise to the preservation of synthetic DNA with bioinorganic materials such as calcium phosphate (CaP). Accelerated aging experiments at elevated temperature and humidity displayed a positive effect of co-precipitated, crystalline dicalcium phosphate on the stability of synthetic DNA in contrast to amorphous CaP. Quantitative PXRD in combination with SEM and EDX measurements revealed distinct CaP phase transformations of calcium phosphate dihydrate (brushite) to anhydrous dicalcium phosphate (monetite) influencing DNA stability.


Assuntos
Materiais Biocompatíveis/química , Fosfatos de Cálcio/química , DNA/química , Teste de Materiais
19.
Nat Commun ; 13(1): 352, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039502

RESUMO

Synthetic DNA is a growing alternative to electronic-based technologies in fields such as data storage, product tagging, or signal processing. Its value lies in its characteristic attributes, namely Watson-Crick base pairing, array synthesis, sequencing, toehold displacement and polymerase chain reaction (PCR) capabilities. In this review, we provide an overview of the most prevalent applications of synthetic DNA that could shape the future of information technology. We emphasize the reasons why the biomolecule can be a valuable alternative for conventional electronic-based media, and give insights on where the DNA-analog technology stands with respect to its electronic counterparts.


Assuntos
DNA/química , Tecnologia da Informação , Redes Neurais de Computação
20.
Commun Biol ; 5(1): 1117, 2022 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-36266439

RESUMO

Synthetic DNA has been proposed as a storage medium for digital information due to its high theoretical storage density and anticipated long storage horizons. However, under all ambient storage conditions, DNA undergoes a slow chemical decay process resulting in nicked (broken) DNA strands, and the information stored in these strands is no longer readable. In this work we design an enzymatic repair procedure, which is applicable to the DNA pool prior to readout and can partially reverse the damage. Through a chemical understanding of the decay process, an overhang at the 3' end of the damaged site is identified as obstructive to repair via the base excision-repair (BER) mechanism. The obstruction can be removed via the enzyme apurinic/apyrimidinic endonuclease I (APE1), thereby enabling repair of hydrolytically damaged DNA via Bst polymerase and Taq ligase. Simulations of damage and repair reveal the benefit of the enzymatic repair step for DNA data storage, especially when data is stored in DNA at high storage densities (=low physical redundancy) and for long time durations.


Assuntos
Reparo do DNA , DNA Liase (Sítios Apurínicos ou Apirimidínicos) , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , DNA/genética , Armazenamento e Recuperação da Informação , Desoxirribonuclease I , Ligases
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