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1.
Trends Biochem Sci ; 44(6): 484-489, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30744927

RESUMEN

In extreme conditions ketosis can progress to ketoacidosis, a dangerous and potentially life-threatening condition. Ketoacidosis is most common in new or poorly treated type 1 diabetes. The acidosis is usually attributed to the 'acidic' nature of the ketone bodies (acetoacetate, 3-hydroxybutyrate, and acetone). However, acetoacetate and 3-hydroxybutyrate are produced not as acids but as their conjugate bases, and acetone is neither an acid nor a base. This raises the question of why severe ketosis is accompanied by acidosis. Here, we analyze steps in ketogenesis and identify four potential sources: adipocyte lipolysis, hydrolysis of inorganic pyrophosphate generated during synthesis of fatty acyl-coenzyme A (CoA), the reaction catalyzed by an enzyme in the ß-oxidation pathway (3-hydroxyacyl-CoA dehydrogenase), and increased synthesis of CoA.


Asunto(s)
Cetosis/metabolismo , Protones , Acilcoenzima A/biosíntesis , Adipocitos/metabolismo , Animales , Humanos , Hidrólisis , Lipólisis
2.
Plant Cell Physiol ; 61(7): 1335-1347, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32379869

RESUMEN

Alpha-linolenic acid (ALA, 18:3Δ9,12,15) and γ-linolenic acid \ (GLA, 18:3Δ6,9,12) are important trienoic fatty acids, which are beneficial for human health in their own right, or as precursors for the biosynthesis of long-chain polyunsaturated fatty acids. ALA and GLA in seed oil are synthesized from linoleic acid (LA, 18:2Δ9,12) by the microsomal ω-3 fatty acid desaturase (FAD3) and Δ6 desaturase (D6D), respectively. Cotton (Gossypium hirsutum L.) seed oil composition was modified by transforming with an FAD3 gene from Brassica napus and a D6D gene from Echium plantagineum, resulting in approximately 30% ALA and 20% GLA, respectively. The total oil content in transgenic seeds remained unaltered relative to parental seeds. Despite the use of a seed-specific promoter for transgene expression, low levels of GLA and increased levels of ALA were found in non-seed cotton tissues. At low temperature, the germinating cottonseeds containing the linolenic acid isomers elongated faster than the untransformed controls. ALA-producing lines also showed higher photosynthetic rates at cooler temperature and better fiber quality compared to both untransformed controls and GLA-producing lines. The oxidative stability of the novel cottonseed oils was assessed, providing guidance for potential food, pharmaceutical and industrial applications of these oils.


Asunto(s)
Fibra de Algodón , Aceite de Semillas de Algodón/metabolismo , Germinación/genética , Gossypium/genética , Fotosíntesis/genética , Semillas/crecimiento & desarrollo , Ácido alfa-Linolénico/metabolismo , Ácido gammalinolénico/metabolismo , Brassica napus/genética , Respuesta al Choque por Frío , Fibra de Algodón/normas , Ácido Graso Desaturasas/genética , Ácido Graso Desaturasas/metabolismo , Ingeniería Genética , Gossypium/metabolismo , Plantas Modificadas Genéticamente , Semillas/metabolismo , Ácido alfa-Linolénico/genética , Ácido gammalinolénico/genética
3.
Plant Biotechnol J ; 16(10): 1788-1796, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29509999

RESUMEN

Vegetable oils extracted from oilseeds are an important component of foods, but are also used in a range of high value oleochemical applications. Despite being biodegradable, nontoxic and renewable current plant oils suffer from the presence of residual polyunsaturated fatty acids that are prone to free radical formation that limit their oxidative stability, and consequently shelf life and functionality. Many decades of plant breeding have been successful in raising the oleic content to ~90%, but have come at the expense of overall field performance, including poor yields. Here, we engineer superhigh oleic (SHO) safflower producing a seed oil with 93% oleic generated from seed produced in multisite field trials spanning five generations. SHO safflower oil is the result of seed-specific hairpin-based RNA interference of two safflower lipid biosynthetic genes, FAD2.2 and FATB, producing seed oil containing less than 1.5% polyunsaturates and only 4% saturates but with no impact on lipid profiles of leaves and roots. Transgenic SHO events were compared to non-GM safflower in multisite trial plots with a wide range of growing season conditions, which showed no evidence of impact on seed yield. The oxidative stability of the field-grown SHO oil produced from various sites was 50 h at 110°C compared to 13 h for conventional ~80% oleic safflower oils. SHO safflower produces a uniquely stable vegetable oil across different field conditions that can provide the scale of production that is required for meeting the global demands for high stability oils in food and the oleochemical industry.


Asunto(s)
Carthamus tinctorius/metabolismo , Ácidos Oléicos/metabolismo , Interferencia de ARN , Aceite de Cártamo/química , Semillas/metabolismo , Carthamus tinctorius/genética , Oxidación-Reducción
4.
Plant Biotechnol J ; 15(1): 132-143, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27381745

RESUMEN

Palmitic acid (C16:0) already makes up approximately 25% of the total fatty acids in the conventional cotton seed oil. However, further enhancements in palmitic acid content at the expense of the predominant unsaturated fatty acids would provide increased oxidative stability of cotton seed oil and also impart the high melting point required for making margarine, shortening and confectionary products free of trans fatty acids. Seed-specific RNAi-mediated down-regulation of ß-ketoacyl-ACP synthase II (KASII) catalysing the elongation of palmitoyl-ACP to stearoyl-ACP has succeeded in dramatically increasing the C16 fatty acid content of cotton seed oil to well beyond its natural limits, reaching up to 65% of total fatty acids. The elevated C16 levels were comprised of predominantly palmitic acid (C16:0, 51%) and to a lesser extent palmitoleic acid (C16:1, 11%) and hexadecadienoic acid (C16:2, 3%), and were stably inherited. Despite of the dramatic alteration of fatty acid composition and a slight yet significant reduction in oil content in these high-palmitic (HP) lines, seed germination remained unaffected. Regiochemical analysis of triacylglycerols (TAG) showed that the increased levels of palmitic acid mainly occurred at the outer positions, while C16:1 and C16:2 were predominantly found in the sn-2 position in both TAG and phosphatidylcholine. Crossing the HP line with previously created high-oleic (HO) and high-stearic (HS) genotypes demonstrated that HP and HO traits could be achieved simultaneously; however, elevation of stearic acid was hindered in the presence of high level of palmitic acid.


Asunto(s)
3-Oxoacil-(Proteína Transportadora de Acil) Sintasa/genética , Aceite de Semillas de Algodón/análisis , Regulación hacia Abajo , Mejoramiento Genético , Gossypium/enzimología , Gossypium/genética , Ácido Palmítico/análisis , Interferencia de ARN , Agrobacterium tumefaciens/genética , Secuencia de Bases , Aceite de Semillas de Algodón/química , Ácidos Grasos/análisis , Ácidos Grasos/química , Ácidos Grasos Monoinsaturados/química , Silenciador del Gen , Genes de Plantas , Vectores Genéticos , Genotipo , Germinación , Lípidos/análisis , Lípidos/química , Estrés Oxidativo , Ácido Palmítico/química , Fosfatidilcolinas/análisis , Filogenia , Aceites de Plantas/análisis , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/metabolismo , Semillas/genética , Alineación de Secuencia , Ácidos Esteáricos/análisis , Transformación Genética , Triglicéridos/análisis
5.
Metab Eng ; 39: 237-246, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27993560

RESUMEN

Synthesis and accumulation of plant oils in the entire vegetative biomass offers the potential to deliver yields surpassing those of oilseed crops. However, current levels still fall well short of those typically found in oilseeds. Here we show how transcriptome and biochemical analyses pointed to a futile cycle in a previously established Nicotiana tabacum line, accumulating up to 15% (dry weight) of the storage lipid triacylglycerol in leaf tissue. To overcome this metabolic bottleneck, we either silenced the SDP1 lipase or overexpressed the Arabidopsis thaliana LEC2 transcription factor in this transgenic background. Both strategies independently resulted in the accumulation of 30-33% triacylglycerol in leaf tissues. Our results demonstrate that the combined optimization of de novo fatty acid biosynthesis, storage lipid assembly and lipid turnover in leaf tissue results in a major overhaul of the plant central carbon allocation and lipid metabolism. The resulting further step changes in oil accumulation in the entire plant biomass offers the possibility of delivering yields that outperform current oilseed crops.


Asunto(s)
Mejoramiento Genético/métodos , Ingeniería Metabólica/métodos , Redes y Vías Metabólicas/fisiología , Nicotiana/fisiología , Hojas de la Planta/fisiología , Aceites de Plantas/metabolismo , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Aceites de Plantas/aislamiento & purificación , Factores de Transcripción/genética
6.
Plant Biotechnol J ; 14(1): 323-31, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25998013

RESUMEN

High oleic oil is an important industrial feedstock that has been one of the main targets for oil improvement in a number of oil crops. Crambe (Crambe abyssinica) is a dedicated oilseed crop, suitable for industrial oil production. In this study, we down-regulated the crambe fatty acid desaturase (FAD) and fatty acid elongase (FAE) genes for creating high oleic seed oil. We first cloned the crambe CaFAD2, CaFAD3 and CaFAE1 genes. Multiple copies of each of these genes were isolated, and the highly homologous sequences were used to make RNAi constructs. These constructs were first tested in Arabidopsis, which led to the elevated oleic or linoleic levels depending on the genes targeted, indicating that the RNAi constructs were effective in regulating the expression of the target genes in nonidentical but closely related species. Furthermore, down-regulation of CaFAD2 and CaFAE1 in crambe with the FAD2-FAE1 RNAi vector resulted in even more significant increase in oleic acid level in the seed oil with up to 80% compared to 13% for wild type. The high oleic trait has been stable in subsequent five generations and the GM line grew normally in greenhouse. This work has demonstrated the great potential of producing high oleic oil in crambe, thus contributing to its development into an oil crop platform for industrial oil production.


Asunto(s)
Acetiltransferasas/metabolismo , Arabidopsis/genética , Crambe (Planta)/enzimología , Regulación hacia Abajo , Ácido Graso Desaturasas/metabolismo , Ácido Oléico/metabolismo , Aceites de Plantas/metabolismo , Semillas/metabolismo , Southern Blotting , Segregación Cromosómica/genética , Elongasas de Ácidos Grasos , Dosificación de Gen , Regulación de la Expresión Génica de las Plantas , Silenciador del Gen , Genes de Plantas , Familia de Multigenes , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Reacción en Cadena de la Polimerasa , ARN Mensajero/genética , ARN Mensajero/metabolismo , Especificidad de la Especie
7.
Plant Cell Rep ; 34(4): 643-53, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25604988

RESUMEN

KEY MESSAGE: Simultaneous gene silencing of both FAD2 genes in high linoleic acid flax leads to high level of oleic acid, which is stable across multiple generations. High oleic oil is one of the preferred traits in oil crop engineering due to its stability and multiple applications as an industrial feedstock. Flax possesses two isoforms of FAD2 enzymes that desaturate monounsaturated oleic acid to polyunsaturated linoleic acid. These two enzymes are encoded by two FAD2 genes. By simultaneous gene silencing both FAD2 genes in high linoleic acid flax, Linola, high level of oleic acid up to 80% was achieved in 69 silencing lines. The high oleic trait was stable across multiple generations with oleic acid reaching up to 77% in homozygote T3 progeny. The RNAi-mediated gene-silencing approach generated high oleic linseed oil, as well as a high oleic platform that can be exploited for further fatty acid engineering.


Asunto(s)
Productos Agrícolas/genética , Ácido Graso Desaturasas/genética , Lino/enzimología , Lino/genética , Genes de Plantas , Ácido Oléico/metabolismo , Interferencia de ARN , Secuencia de Bases , Segregación Cromosómica , Regulación de la Expresión Génica de las Plantas , Patrón de Herencia/genética , Datos de Secuencia Molecular , Plantas Modificadas Genéticamente , Carácter Cuantitativo Heredable , Semillas/genética , Homología de Secuencia de Ácido Nucleico , Transformación Genética
8.
J Biol Chem ; 288(52): 36902-14, 2013 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-24189065

RESUMEN

Acyl-CoA:lysophosphatidylcholine acyltransferase (LPCAT) enzymes have central roles in acyl editing of phosphatidylcholine (PC). Plant LPCAT genes were expressed in yeast and characterized biochemically in microsomal preparations of the cells. Specificities for different acyl-CoAs were similar for seven LPCATs from five different species, including species accumulating hydroxylated acyl groups in their seed oil, with a preference for C18-unsaturated acyl-CoA and low activity with palmitoyl-CoA and ricinoleoyl (12-hydroxyoctadec-9-enoyl)-CoA. We showed that Arabidopsis LPCAT1 and LPCAT2 enzymes catalyzed the acylation and de-acylation of both sn positions of PC, with a preference for the sn-2 position. When acyl specificities of the Arabidopsis LPCATs were measured in the reverse reaction, sn-2-bound oleoyl, linoleoyl, and linolenoyl groups from PC were transferred to acyl-CoA to a similar extent. However, a ricinoleoyl group at the sn-2-position of PC was removed 4-6-fold faster than an oleoyl group in the reverse reaction, despite poor utilization in the forward reaction. The data presented, taken together with earlier published reports on in vivo lipid metabolism, support the hypothesis that plant LPCAT enzymes play an important role in regulating the acyl-CoA composition in plant cells by transferring polyunsaturated and hydroxy fatty acids produced on PC directly to the acyl-CoA pool for further metabolism or catabolism.


Asunto(s)
1-Acilglicerofosfocolina O-Aciltransferasa/química , Proteínas de Arabidopsis/química , Arabidopsis/enzimología , 1-Acilglicerofosfocolina O-Aciltransferasa/genética , 1-Acilglicerofosfocolina O-Aciltransferasa/metabolismo , Acilcoenzima A/química , Acilcoenzima A/genética , Acilcoenzima A/metabolismo , Acilación , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Secuencia de Bases , Catálisis , Ácidos Grasos Insaturados/biosíntesis , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/genética , Datos de Secuencia Molecular , Especificidad de la Especie
9.
Scott Med J ; 59(2): e7-e10, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24682104

RESUMEN

INTRODUCTION: Percutaneous transluminal angioplasty (PTA) is a common therapeutic option for the treatment of peripheral vascular disease. Pseudoaneurysm at the puncture site is a well-documented complication in patients. CASE PRESENTATION: This case report describes a patient who presented to hospital several days following a left superficial femoral and popliteal artery PTA with lower limb pain and swelling. The working diagnosis included a deep vein thrombosis based on the Wells criteria. However, a combination of a duplex scan and computed tomography angiography confirmed a clinically rare occurrence of pseudoaneurysm of the sural artery, a branch of the popliteal artery. This was managed successfully with a thrombin injection, leading to complete resolution of the patient's symptoms. CONCLUSION: This case highlights the importance of the technical aspects of performing a PTA. We believe that the guide-wire position was not confirmed to be completely in the popliteal artery upon inflation of the balloon.


Asunto(s)
Aneurisma Falso/tratamiento farmacológico , Angioplastia de Balón/efectos adversos , Hemostáticos/administración & dosificación , Pierna/irrigación sanguínea , Enfermedades Vasculares Periféricas/cirugía , Arteria Poplítea/fisiopatología , Trombina/administración & dosificación , Anciano , Aneurisma Falso/etiología , Aneurisma Falso/fisiopatología , Angiografía , Presión Sanguínea , Femenino , Humanos , Enfermedades Vasculares Periféricas/fisiopatología , Resultado del Tratamiento , Ultrasonografía Doppler Dúplex
10.
J Diabetes Sci Technol ; : 19322968241264761, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39044480

RESUMEN

BACKGROUND: The growing adoption of diabetes devices has highlighted the need for integrated platforms to consolidate data from various vendors and device types, enhancing the patient experience and treatment. This shift could pave the way for a transition from conventional outpatient diabetes clinics to advanced home monitoring and virtual care methods. Overall, we wished to empower individuals with diabetes and healthcare providers to interpret and utilize information from diabetes devices more effectively. METHODS: Stenopool integrates most diabetes devices for glucose monitoring and insulin administration in our clinic. The platform was initially developed with inspiration from open-source software, and the current version is a unique digital platform for managing and analyzing diabetes device data. The development process, outcomes, and status are described. RESULTS: Since November 2021, Stenopool has been used in our outpatient clinic to integrate over 30 different diabetes devices from around 7000 individuals. Data are primarily uploaded via wired connections, but also using semi-automated and automated cloud-to-cloud data transfers. The platform offers a streamlined workflow for healthcare providers and displays data from various glucose meter, insulin pump, and continuous glucose monitor (CGM) vendors on a single screen in a manner that healthcare providers can modify. A data warehouse with data from Stenopool and electronical health records is nearing completion, preparing the development of tools for population health management, quality assessment, and risk stratification of patients. CONCLUSION: Using Stenopool, we aimed to enhance diabetes device data management, facilitate the future for virtual patient care pathways, and improve outcomes. This article outlines the platform's development process and challenges.

11.
BMC Plant Biol ; 13: 5, 2013 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-23289946

RESUMEN

BACKGROUND: The application and nutritional value of vegetable oil is highly dependent on its fatty acid composition, especially the relative proportion of its two major fatty acids, i.e oleic acid and linoleic acid. Microsomal oleoyl phosphatidylcholine desaturase encoded by FAD2 gene is known to introduce a double bond at the Δ12 position of an oleic acid on phosphatidylcholine and convert it to linoleic acid. The known plant FAD2 enzymes are encoded by small gene families consisting of 1-4 members. In addition to the classic oleate Δ12-desaturation activity, functional variants of FAD2 that are capable of undertaking additional or alternative acyl modifications have also been reported in a limited number of plant species. In this study, our objective was to identify FAD2 genes from safflower and analyse their differential expression profile and potentially diversified functionality. RESULTS: We report here the characterization and functional expression of an exceptionally large FAD2 gene family from safflower, and the temporal and spatial expression profiles of these genes as revealed through Real-Time quantitative PCR. The diversified functionalities of some of the safflower FAD2 gene family members were demonstrated by ectopic expression in yeast and transient expression in Nicotiana benthamiana leaves. CtFAD2-1 and CtFAD2-10 were demonstrated to be oleate desaturases specifically expressed in developing seeds and flower head, respectively, while CtFAD2-2 appears to have relatively low oleate desaturation activity throughout the plant. CtFAD2-5 and CtFAD2-8 are specifically expressed in root tissues, while CtFAD2-3, 4, 6, 7 are mostly expressed in the cotyledons and hypocotyls in young safflower seedlings. CtFAD2-9 was found to encode a novel desaturase operating on C16:1 substrate. CtFAD2-11 is a tri-functional enzyme able to introduce a carbon double bond in either cis or trans configuration, or a carbon triple (acetylenic) bond at the Δ12 position. CONCLUSIONS: In this study, we isolated an unusually large FAD2 gene family with 11 members from safflower. The seed expressed FAD2 oleate Δ12 desaturase genes identified in this study will provide candidate targets to manipulate the oleic acid level in safflower seed oil. Further, the divergent FAD2 enzymes with novel functionality could be used to produce rare fatty acids, such as crepenynic acid, in genetically engineered crop plants that are precursors for economically important phytoalexins and oleochemical products.


Asunto(s)
Carthamus tinctorius/enzimología , Ácido Graso Desaturasas/metabolismo , Proteínas de Plantas/metabolismo , Carthamus tinctorius/clasificación , Carthamus tinctorius/genética , Ácido Graso Desaturasas/genética , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Filogenia , Proteínas de Plantas/genética
12.
Plant Biotechnol J ; 11(2): 197-210, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23190163

RESUMEN

Society has come to rely heavily on mineral oil for both energy and petrochemical needs. Plant lipids are uniquely suited to serve as a renewable source of high-value fatty acids for use as chemical feedstocks and as a substitute for current petrochemicals. Despite the broad variety of acyl structures encountered in nature and the cloning of many genes involved in their biosynthesis, attempts at engineering economic levels of specialty industrial fatty acids in major oilseed crops have so far met with only limited success. Much of the progress has been hampered by an incomplete knowledge of the fatty acid biosynthesis and accumulation pathways. This review covers new insights based on metabolic flux and reverse engineering studies that have changed our view of plant oil synthesis from a mostly linear process to instead an intricate network with acyl fluxes differing between plant species. These insights are leading to new strategies for high-level production of industrial fatty acids and waxes. Furthermore, progress in increasing the levels of oil and wax structures in storage and vegetative tissues has the potential to yield novel lipid production platforms. The challenge and opportunity for the next decade will be to marry these technologies when engineering current and new crops for the sustainable production of oil and wax feedstocks.


Asunto(s)
Alimentación Animal , Ingeniería Metabólica , Aceites de Plantas/metabolismo , Ceras/metabolismo , Ácidos Grasos/biosíntesis , Plantas/metabolismo
13.
Theor Appl Genet ; 126(9): 2219-31, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23695179

RESUMEN

There are two types of safflower oil, high oleic (HO) with 70-75 % oleic acid and high linoleic (HL) with about 70 % linoleic acid. The original HO trait in safflower, found in an introduction from India, is controlled by a partially recessive allele ol at a single locus (Knowles and Bill 1964). In the lipid biosynthesis pathway of developing safflower seeds, microsomal oleoyl phosphatidylcholine desaturase (FAD2) is largely responsible for the conversion of oleic acid to linoleic acid. In vitro microsomal assays indicated drastically reduced FAD2 enzyme activity in the HO genotype compared to conventional HL safflower. A previous study indicated that a single-nucleotide deletion was found in the coding region of CtFAD2-1 that causes premature termination of translation in the HO genotypes, and the expression of the mutant CtFAD2-1Δ was attenuated in the HO genotypes compared to conventional HL safflower (Guan et al. 2012). In this study, we hypothesise that down-regulation of CtFAD2-1 expression in the HO genotype may be explained by nonsense-mediated RNA decay (NMD). NMD phenomenon, indicated by gene-specific RNA degradation of defective CtFAD2-1Δ, was subsequently confirmed in Arabidopsis thaliana seed as well as in the transient expression system in Nicotiana benthamiana leaves. We have developed a perfect molecular marker corresponding to the olol mutation that can facilitate a rapid screening and early detection of genotypes carrying the olol mutation for use in marker-assisted selection for the management of the HO trait in safflower breeding programmes.


Asunto(s)
Carthamus tinctorius/genética , Ácido Graso Desaturasas/genética , Degradación de ARNm Mediada por Codón sin Sentido/genética , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/genética , Proteínas de Plantas/genética , Alelos , Arabidopsis/química , Arabidopsis/genética , Secuencia de Bases , Carthamus tinctorius/enzimología , Regulación hacia Abajo , Ácido Graso Desaturasas/metabolismo , Regulación de la Expresión Génica de las Plantas , Marcadores Genéticos , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , India , Ácido Linoleico/biosíntesis , Datos de Secuencia Molecular , Mutación , Ácido Oléico/biosíntesis , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/metabolismo , Fenotipo , Hojas de la Planta/química , Aceites de Plantas/química , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/genética , Semillas/química , Alineación de Secuencia , Análisis de Secuencia de ADN , Nicotiana/química , Nicotiana/genética
14.
Diabetes Care ; 46(11): 1958-1964, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37610784

RESUMEN

OBJECTIVE: This study aimed to investigate the association between continuous glucose monitoring (CGM)-derived glycemic metrics and different insulin treatment modalities using real-world data. RESEARCH DESIGN AND METHODS: A cross-sectional study at Steno Diabetes Center Copenhagen, Denmark, included individuals with type 1 diabetes using CGM. Data from September 2021 to August 2022 were analyzed if CGM was used for at least 20% of a 4-week period. Individuals were divided into four groups: multiple daily injection (MDI) therapy, insulin pumps with unintegrated CGM (SUP), sensor-augmented pumps with low glucose management (SAP), and automated insulin delivery (AID). The MDI and SUP groups were further subdivided based on CGM alarm features. The primary outcome was percentage of time in range (TIR: 3.9-10.0 mmol/L) for each treatment group. Secondary outcomes included other glucose metrics and HbA1c. RESULTS: Out of 6,314 attendees, 3,184 CGM users were included in the analysis. Among them, 1,622 used MDI, 504 used SUP, 354 used SAP, and 561 used AID. Median TIR was 54.0% for MDI, 54.9% for SUP, 62,9% for SAP, and 72,1% for AID users. The proportion of individuals achieving all recommended glycemic targets (TIR >70%, time above range <25%, and time below range <4%) was significantly higher in SAP (odds ratio [OR] 2.4 [95% CI 1.6-3.5]) and AID (OR 9.4 [95% CI 6.7-13.0]) compared with MDI without alarm features. CONCLUSIONS: AID appears superior to other insulin treatment modalities with CGM. Although bias may be present because of indications, AID should be considered the preferred choice for insulin pump therapy.


Asunto(s)
Diabetes Mellitus Tipo 1 , Humanos , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Automonitorización de la Glucosa Sanguínea , Glucemia , Estudios Transversales , Insulina/uso terapéutico , Sistemas de Infusión de Insulina , Insulina Regular Humana/uso terapéutico
15.
J Biol Chem ; 286(51): 43644-43650, 2011 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-22041902

RESUMEN

Caenorhabditis elegans FAT-2 has been characterized as fatty acid Δ12-desaturase able to desaturate C16 and C18 fatty acids. However, in this report we show that when expressed in yeast cells this enzyme can also catalyze Δ15 desaturation. This results in the production of both linoleic acid (ω6 C18:2Δ9,12) and linolenic acid (ω3 C18:3Δ9,12,15) from oleic acid (C18:1Δ9) substrate, and hexadecadienoic acid (ω4 C16:2Δ9,12) and hexadecatrienoic acid (ω1 C16:3Δ9,12,15) from palmitoleic acid (C16:1Δ9) substrate. In addition, this enzyme can also produce C14:2Δ9,12, C15:2Δ9,12, C17:2Δ9,12, and C18:4Δ6,9,12,15 when C14:1Δ9, C15:1Δ9, C17:1Δ9, and C18:3Δ6,9,12 substrates are available in yeast cells. Mass spectrometry analysis of 2,4-dimethyloxazoline modification of fatty acid methyl esters confirms the positions of all newly formed double bonds. These results indicate that when expressed in yeast the C. elegans Δ12-desaturase CeFAT-2 shows a characteristic of a bifunctional Δ12/Δ15-desaturase and has a great deal of elasticity with respect to fatty acid chain length in being able to accept fatty acids ranging from C14 to C18. Interestingly, despite possessing a bifunctional Δ12/Δ15 desaturation activity, phylogenetic analysis suggests that C. elegans Δ12-desaturase CeFAT-2 might have arisen independently from other reported dual Δ12/Δ15-desaturases from fungi and protozoa.


Asunto(s)
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Ácido Graso Desaturasas/metabolismo , Regulación de la Expresión Génica , Animales , Cromatografía de Gases/métodos , Clonación Molecular , Ácidos Grasos/química , Ácidos Grasos Monoinsaturados/química , Ácidos Grasos Insaturados/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Ácido Linoleico/química , Metabolismo de los Lípidos , Modelos Genéticos , Ácido Oléico/química , Filogenia , Unión Proteica
16.
J Biol Chem ; 286(15): 12860-9, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21300802

RESUMEN

Membrane-bound fatty acid desaturases and related enzymes play a pivotal role in the biosynthesis of unsaturated and various unusual fatty acids. Structural insights into the remarkable catalytic diversity and wide range of substrate specificities of this class of enzymes remain limited due to the lack of a crystal structure. To investigate the structural basis of the double bond positioning (regioselectivity) of the desaturation reaction in more detail, we relied on a combination of directed evolution in vitro and a powerful yeast complementation assay to screen for Δx regioselectivity. After two selection rounds, variants of the bifunctional Δ12/Δ9-desaturase from the house cricket (Acheta domesticus) exhibited increased Δ9-desaturation activity on shorter chain fatty acids. This change in specificity was the result of as few as three mutations, some of them near the putative active site. Subsequent analysis of individual substitutions revealed an important role of residue Phe-52 in facilitating Δ9-desaturation of shorter chain acyl substrates and allowed for the redesign of the cricket Δ12/Δ9-desaturase into a 16:0-specific Δ9-desaturase. Our results demonstrate that a minimal number of mutations can have a profound impact on the regioselectivity of acyl-CoA fatty acid desaturases and include the first biochemical data supporting the acyl-CoA acyl carrier specificity of a desaturase able to carry out Δ12-desaturation.


Asunto(s)
Evolución Molecular Dirigida , Ácido Graso Desaturasas/química , Gryllidae/enzimología , Proteínas de Insectos/química , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Dominio Catalítico , Ácido Graso Desaturasas/genética , Ácido Graso Desaturasas/metabolismo , Ácidos Grasos/química , Ácidos Grasos/genética , Ácidos Grasos/metabolismo , Gryllidae/genética , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Datos de Secuencia Molecular , Mutación Missense , Saccharomyces cerevisiae , Relación Estructura-Actividad , Especificidad por Sustrato/fisiología
17.
JMIR Res Protoc ; 11(10): e37626, 2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36190744

RESUMEN

BACKGROUND: Studies have shown that there may be dissimilar perceptions on symptoms or side effects between patients with cancer and health care professionals. This may lead to symptomatic patients notifying the clinic irregularly or not telling the clinic at all. Wearables could help identify symptoms earlier. Patients with low socioeconomic status and less self-awareness of their health may benefit from this. A new design of wearables is a smart t-shirt that, with embedded sensors, provides measurement flows such as electrocardiogram, thoracic and abdominal respiration, and temperature. OBJECTIVE: This study evaluates the feasibility of using a smart t-shirt for home monitoring of biometric sensor data in adolescent and young adult and elderly patients during cancer treatment. METHODS: The OncoSmartShirt study is an explorative study investigating the feasibility of using the Chronolife smart t-shirt during cancer treatment. This smart t-shirt is designed with multiple fully embedded sensors and electrodes that engender 6 different measurement flows continuously. A total of 20 Danish patients with cancer ≥18 years old in antineoplastic treatment at Department of Oncology Rigshospitalet Denmark will be recruited from all cancer wards, whether patients are in curative or palliative care. Of these 20 patients, 10 (50%) will be <39 years old, defined as adolescent and young adult, and 10 (50%) will be patients >65 years old, defined as elderly. Consenting patients will be asked to wear a smart t-shirt daily for 2 weeks during their treatment course. RESULTS: The primary outcome is to determine if it is feasible to wear a smart t-shirt throughout the day (preferably 8 hours per day) for 2 weeks. Inclusion of patients started in March 2022. CONCLUSIONS: The study will assess the feasibility of using the Chronolife smart t-shirt for home monitoring of vital parameters in patients with cancer during their treatment and bring new insights into how wearables and biometric data can be used as part of symptom or side-effect recognition in patients with cancer during treatment, with the aim to increase patients' quality of life. TRIAL REGISTRATION: ClinicalTrials.gov NCT05235594; https://beta.clinicaltrials.gov/study/NCT05235594. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/37626.

18.
Sci Total Environ ; 835: 155495, 2022 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-35472357

RESUMEN

Poikilohydric autotrophs are the main colonizers of the permanent ice-free areas in the Antarctic tundra biome. Global climate warming and the small human footprint in this ecosystem make it especially vulnerable to abrupt changes. Elucidating the effects of climate change on the Antarctic ecosystem is challenging because it mainly comprises poikilohydric species, which are greatly influenced by microtopographic factors. In the present study, we investigated the potential effects of climate change on the metabolic activity and net primary photosynthesis (NPP) in the widespread lichen species Usnea aurantiaco-atra. Long-term monitoring of chlorophyll a fluorescence in the field was combined with photosynthetic performance measurements in laboratory experiments in order to establish the daily response patterns under biotic and abiotic factors at micro- and macro-scales. Our findings suggest that macroclimate is a poor predictor of NPP, thereby indicating that microclimate is the main driver due to the strong effects of microtopographic factors on cryptogams. Metabolic activity is also crucial for estimating the NPP, which is highly dependent on the type, distribution, and duration of the hydration sources available throughout the year. Under RCP 4.5 and RCP 8.5, metabolic activity will increase slightly compared with that at present due to the increased precipitation events predicted in MIROC5. Temperature is highlighted as the main driver for NPP projections, and thus climate warming will lead to an average increase in NPP of 167-171% at the end of the century. However, small changes in other drivers such as light and relative humidity may strongly modify the metabolic activity patterns of poikilohydric autotrophs, and thus their NPP. Species with similar physiological response ranges to the species investigated in the present study are expected to behave in a similar manner provided that liquid water is available.


Asunto(s)
Líquenes , Unionidae , Animales , Clorofila A , Cambio Climático , Ecosistema , Humanos , Líquenes/fisiología , Fotosíntesis , Tundra
19.
JMIR Res Protoc ; 10(5): e26096, 2021 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-33983123

RESUMEN

BACKGROUND: Patients with head and neck cancer (HNC) experience severe side effects during radiotherapy (RT). Ongoing technological advances in wearable biometric sensors allow for the collection of objective data (eg, physical activity and heart rate), which might, in the future, help detect and counter side effects before they become severe. A smartwatch such as the Apple Watch allows for objective data monitoring outside the hospital with minimal effort from the patient. To determine whether such tools can be implemented in the oncological setting, feasibility studies are needed. OBJECTIVE: This protocol describes the design of the OncoWatch 1.0 feasibility study that assesses the adherence of patients with HNC to an Apple Watch during RT. METHODS: A prospective, single-cohort trial will be conducted at the Department of Oncology, Rigshospitalet (Copenhagen, Denmark). Patients aged ≥18 years intended for primary or postoperative curatively intended RT for HNC will be recruited. Consenting patients will be asked to wear an Apple Watch on the wrist during and until 2 weeks after RT. The study will include 10 patients. Data on adherence, data acquisition, and biometric data will be collected. Demographic data, objective toxicity scores, and hospitalizations will be documented. RESULTS: The primary outcome is to determine if it is feasible for the patients to wear a smartwatch continuously (minimum 12 hours/day) during RT. Furthermore, we will explore how the heart rate and physical activity change over the treatment course. CONCLUSIONS: The study will assess the feasibility of using the Apple Watch for home monitoring of patients with HNC. Our findings may provide novel insights into the patient's activity levels and variations in heart rate during the treatment course. The knowledge obtained from this study will be essential for further investigating how biometric data can be used as part of symptom monitoring for patients with HNC. TRIAL REGISTRATION: ClinicalTrials.gov NCT04613232; https://clinicaltrials.gov/ct2/show/NCT04613232. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/26096.

20.
Front Plant Sci ; 11: 727, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32595662

RESUMEN

Plant seeds have long been promoted as a production platform for novel fatty acids such as the ω3 long-chain (≥ C20) polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) commonly found in fish oil. In this article we describe the creation of a canola (Brassica napus) variety producing fish oil-like levels of DHA in the seed. This was achieved by the introduction of a microalgal/yeast transgenic pathway of seven consecutive enzymatic steps which converted the native substrate oleic acid to α-linolenic acid and, subsequently, to EPA, docosapentaenoic acid (DPA) and DHA. This paper describes construct design and evaluation, plant transformation, event selection, field testing in a wide range of environments, and oil profile stability of the transgenic seed. The stable, high-performing event NS-B50027-4 produced fish oil-like levels of DHA (9-11%) in open field trials of T3 to T7 generation plants in several locations in Australia and Canada. This study also describes the highest seed DHA levels reported thus far and is one of the first examples of a deregulated genetically modified crop with clear health benefits to the consumer.

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