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1.
Int Urogynecol J ; 33(5): 1059-1070, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35142870

RESUMO

INTRODUCTION AND HYPOTHESIS: Recommendations for preventing and diagnosing recurrent urinary tract infection (UTI) tend to vary between clinical practice guidelines (CPGs) because of low-quality scientific evidence, potentially leading to practice variation and suboptimal care. We assessed the quality of existing CPGs for recurrent UTI. METHODS: A systematic search was performed from January 2000 to June 2021 in PubMed and EMBASE for CPGs on recurrent UTI prevention or hospital diagnostics in Dutch, English, and Spanish. Each CPG was assessed by four appraisers in a multidisciplinary review team, using the Appraisal of Guidelines, Research, and Evaluation II (AGREE II) instrument. RESULTS: We identified and assessed eight CPGs published between 2013 and 2021. The scope and purpose (mean and standard deviation: 67.3 ± 21.8) and clarity of presentation (74.8 ± 17.6) domains scored highly. However, issues with methods, patient participation, conflict of interests, and facilitators and barriers were common and resulted in lower scores for the rigour of development (56.9 ± 25.9), applicability (19.6 ± 23.4), stakeholder involvement (50.4 ± 24.6), and editorial independence (62.1 ± 23.1) domains. Overall, two CPGs were recommended, three were recommended with modifications, and three were not recommended. CONCLUSIONS: Significant room for improvement exists in the quality of CPGs for recurrent UTI, with most displaying serious limitations in the stakeholder involvement, rigour of development, and applicability domains. These aspects must be improved to decrease diagnostic and therapeutic uncertainty. Developers could benefit from using checklists and following guidelines when developing de novo CPGs.


Assuntos
Infecções Urinárias , Humanos , Infecções Urinárias/diagnóstico , Infecções Urinárias/terapia
2.
J Evid Based Med ; 12(2): 113-124, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30511477

RESUMO

BACKGROUND: Red blood cell (RBC) transfusions are essential in health care. The quality of recommendations included in clinical practice guidelines (CPG), regarding this intervention, has not been systematically evaluated. This paper systematically assessed CPGs for RBC-transfusion, to appraise their methodological quality, to explore changes in quality over time, and to assess the consistency of the hemoglobin threshold (HT) recommendations. METHODS: We searched for CPGs that included recommendations of RBC-transfusion in generic databases, compiler entities, registries, clearinghouses and guideline developers. Three reviewers extracted data on CPGs characteristics and HT recommendations, independently appraised the quality of the studies using AGREE II and resolved disagreements by consensus. RESULTS: We examined 16 CPGs. Mean scores (mean ± SD) were: scope and purpose (59.4% ± 19.8%), stakeholder involvement (43.2% ± 22.6%), rigor of development (50% ± 25%), clarity of presentation (74.4% ± 12.6%), applicability (19.4% ± 18.8%), and editorial independence (41% ± 30%). Seven CPGs recommended a restrictive strategy for RBC transfusion; four CPGs gave a guarded statement considering an HT of 7 g/dL, as safe to prescribe an RBC transfusion. Eight CPGs did not provide an HT stating that RBC transfusions should not be prescribed by HT alone. CONCLUSIONS: Only 3 out of the 16 evaluated CPGs were "recommended" by the independent evaluators. Four domains "stakeholder involvement," "rigor of development," applicability," and "editorial independence" had serious shortcomings. Recommendations about the use of an HT for RBC-transfusion were heterogeneous among guidelines. Greater efforts are needed to provide high-quality CPGs in the RBC-transfusion practice.


Assuntos
Transfusão de Eritrócitos , Guias de Prática Clínica como Assunto/normas , Políticas Editoriais , Hemoglobinas/metabolismo , Humanos , Participação dos Interessados
3.
J Exp Bot ; 69(16): 4113-4126, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-29860511

RESUMO

Phytoene synthase (PSY) is the first committed enzyme of the carotenoid biosynthesis pathway and the most important point of regulation. Carotenoids are precursors of abscisic acid (ABA), which mediates abiotic stress tolerance responses in plants. ABA activates the synthesis of its own precursors through induction of PSY expression. Carrot, a species that accumulates very high amounts of carotenoids in its reserve root, has two PSY paralog genes that are expressed differentially in the root. Here, we determined that DcPSY2 expression is induced by salt stress and ABA. A DcPSY2 promoter fragment was obtained and characterized. Bioinformatic analysis showed the presence of three ABA responsive elements (ABREs). Through overexpressing pPSY2:GFP in Nicotiana tabacum we determined that all three ABREs are necessary for the ABA response. In the carrot transcriptome, we identified three ABRE binding protein (DcAREB) transcription factor candidates that localized in the nucleus, but only one, DcAREB3, was induced under ABA treatment in carrot roots. We found that AREB transcription factors bind to the carrot DcPSY2 promoter and transactivate the expression of reporter genes. We conclude that DcPSY2 is involved in ABA-mediated salt stress tolerance in carrot through the binding of AREB transcription factors to its promoter.


Assuntos
Ácido Abscísico/metabolismo , Daucus carota/metabolismo , Geranil-Geranildifosfato Geranil-Geraniltransferase/biossíntese , Estresse Salino , Daucus carota/genética , Indução Enzimática , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas
4.
Curr Opin Biotechnol ; 49: 10-15, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28738208

RESUMO

Metabolic pathway engineering by transgene expression from the plastid (chloroplast) genome offers significant attractions, including straightforward multigene engineering by pathway expression from operons, high transgene expression levels, and increased transgene containment due to maternal inheritance of plastids in most crops. In addition, it provides direct access to the large and diverse metabolite pools in chloroplasts and non-green plastid types. Here, we review recent progress with extending the toolbox for plastid engineering and highlight selected applications in the area of metabolic engineering, including the combined engineering of nuclear and plastid genomes for the production of artemisinic acid, the direct harness of chloroplast reducing power for the synthesis of dhurrin and the use of an edible host for the production of astaxanthin.


Assuntos
Engenharia Metabólica , Plastídeos/metabolismo , Transformação Genética , Antioxidantes/metabolismo , Plantas Geneticamente Modificadas , Transgenes
5.
Life Sci Soc Policy ; 13(1): 6, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28447286

RESUMO

The aim of this manuscript is to highlight that from the phenomenology and psychoanalysis point of view, the meaning of the notion of the body is different from the medical biologicist discourse. In psychoanalysis, the body is an erogenized body. It is constituted as an object for another self. Similarly, in phenomenology, the body is an own body in first instance. It is the body of a self, rather than a living body and a material body. Both positions enable us to understand how this conceptualization of the body is essential in any human field. Especially in the clinic, the position of the subject before the other will lead to a specific form of intervention. From this understanding of the human body, both phenomenology and psychoanalysis confirm that the biologicist understanding of the body, presumed by all psychological and medical practices, is insufficient.


Assuntos
Corpo Humano , Psicanálise , Autoimagem , Formação de Conceito , Humanos
6.
Med Clin (Barc) ; 149(3): 101-106, 2017 Aug 10.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28408109

RESUMO

BACKGROUND AND OBJECTIVE: Recent reports of outbreaks of lipoatrophia semicircularis (LS) in various countries have generated discussion regarding the potential role of the environmental characteristics of office workplaces in new buildings. The objective of this study was to investigate a suspected outbreak of LS among children in a public school in Barcelona, which generated tremendous alarm. METHODS: We performed an epidemiological assessment including descriptive and prevalence analyses, and an environmental investigation followed by a psychiatric assessment according to Small's criteria. We compared the prevalence of LS and its 95% confidence interval between children and staff attending the day-care centre under study and other centres. RESULTS: Among 86 children attending a day-care centre we detected 11 confirmed and 2 possible cases of LS (15.1%) while among 41 children attending other day-care centres we identified 8 cases and 4 possible cases (29.3%) (P=.10). Among 12 day-care staff, we detected 8 cases of LS (66.7%) while among 19 women working different jobs we identified 14 with the same condition as the staff (73.7%) (P=.98). All lesions were finally classified as indentations with different locations. The environmental evaluation didn't identify any exposure factors with a significant role in the onset of the outbreak. The outbreak shared 13 of Small's 16 criteria regarding epidemic somatoform disorder ("mass hysteria"). CONCLUSION: The presence of indentations can be considered a normal variant in the lower extremities of children. The characteristic development of the process leads us to the conclusion that this outbreak was an epidemic somatoform disorder.


Assuntos
Surtos de Doenças , Lipodistrofia/epidemiologia , Transtornos Somatoformes/epidemiologia , Pré-Escolar , Feminino , Humanos , Lactente , Lipodistrofia/diagnóstico , Lipodistrofia/etiologia , Masculino , Prevalência , Fatores de Risco , Transtornos Somatoformes/diagnóstico , Transtornos Somatoformes/etiologia , Espanha/epidemiologia
7.
Rev. chil. dermatol ; 33(3): 93-96, 2017. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-965059

RESUMO

La acropaquia es un trastorno que puede presentarse en forma aislada o formar parte del síndrome de osteoartropatía hipertrófica, entidad caracterizada por periostosis, dolor articular y acropaquia. Cuando este síndrome es causado por una mutación genética específica, se denomina osteoartropatía hipertrófica primaria. Este raro desorden hereditario se asocia, además, a alteraciones dermatológicas típicas, como hiperseborrea, acné, engrosamiento de pliegues faciales, entre otras. Una asociación rara vez descrita es la queratodermia palmoplantar. Se presenta el caso de una mujer de 46 años con osteoartropatía hipertrófica primaria asociada a queratodermia palmoplantar que asistió a la unidad de dermatología del Hospital Gustavo Fricke, Viña del Mar, Chile.


Clubbing is a disorder that can be an isolated finding or be part of the hypertrophic osteoarthropathy syndrome, an entity characterized by periostosis, joint pain and clubbing. When this syndrome is caused by a specific genetic mutation, it is called primary hypertrophic osteoarthropathy. This rare hereditary disorder is also associated with typical dermatological findings, such as hyperseborrhea, acne and facial feature coarsening. An association rarely described is palmoplantar keratoderma. We present the case of a 46-year-old woman with primary hypertrophic osteoarthropathy and palmoplantar keratoderma who came to the dermatology unit of Gustavo Fricke Hospital, Viña del Mar, Chile.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Osteoartropatia Hipertrófica Primária/diagnóstico , Osteoartropatia Hipertrófica Primária/etiologia , Ceratodermia Palmar e Plantar/complicações
8.
Bol. Hosp. Viña del Mar ; 73(2): 52-53, 2017.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1398295

RESUMO

El eritema ab igne es una enfermedad cutánea inusual causada por la exposición crónica de la piel al calor en niveles menores de los necesarios para que ocurra una quemadura. Clínicamente se caracteriza por la presencia de telangiectasias reticuladas e hiperpigmentación de la piel. Su sitio de aparición típico es la zona anterior de los muslos, habitualmente en mujeres que se exponen a una fuente cercana de calor. No existe tratamiento efectivo descrito en la literatura actual y su progresión solo puede prevenirse mediante la eliminación de la exposición al calor. Presentamos un caso de una mujer de 50 años con antecedentes de esclerosis múltiple y psoriasis, que consultó por mácula hiperpigmentada e indolora localizada en región anterior de ambos muslos, de un mes de evolución, que apareció luego de la aplicación de almohadilla térmica por 2 semanas en zona descrita. Al examen físico destacaba la presencia de mácula hiperpigmentada de bordes difuminados, aspecto reticular, color marrón rojizo oscuro, localizada en región anterior de ambos muslos. Se realizó diagnóstico clínico de eritema ab igne, indicándose suspensión del uso de almohadilla térmica. No se indicó manejo específico. Actualmente persiste con hiperpigmentación.


Erythema ab igne is an unusual skin disease caused by chronic exposure to heat at levels too low to cause burns. It is characterized clinically by reticulated telangiectasias and hyperpigmentation of the skin. It is typically seen in anterior thighs, usually in women exposed to a close source of heat. No effective treatment has been described in the literature and progression can be prevented only by suspending the exposure to heat. We present the case of a 50 year old woman with multiple sclerosis and psoriasis who complained of painless hyperpigmented macules on both anterior thighs of one month duration after using a thermal cushion on the region for two weeks. She had dark reddish brown hyper-pigmented, reticulated macules with diffuse borders on each anterior thigh. Erythema ab igne was diagnosed and the use of the thermal cushion was discontinued. No specific treatment was given. The hyperpigmentation persisted.

9.
Memorandum ; 31: 206-217, out. 2016.
Artigo em Espanhol | LILACS | ID: biblio-914657

RESUMO

Desde la aproximación fenomenológica que realiza Edith Stein para la comprensión de la estructura óntica y dinamismo de la acción propiamente humana, se puede considerar la empatía como un acto propio de la persona, el cual está presente en la constitución del individuo psicofísico, y es desde donde se establece el dinamismo perfectivo de ésta. Dando lugar así, a la comprensión de la persona como un ser-con-los-demás, desde donde se establecerán las bases para una ética de la persona considerada en su ser relacional, eludiendo cualquier posible individualismo. La persona al ser una estructura abierta, abierta hacia dentro y hacia fuera, hacia sí mismo y hacia el otro, permite la fundamentación de un ethos relacional, del Yo-Tú, del que emerge el nosotros, y por tanto una comprensión más acabada del bien común.(AU)


From the phenomenological approach that Edith Stein proposed, for understanding the ontological structure and dynamism of human action, empathy can be considered as an act of the person, which is present in the constitution of the Psycho-physical Individual, and establish the perfective dynamism of the person. Leading to the understanding of the person as a being - with -others, from where establishes the basis of an ethic that consider the individual as a relational being, avoiding any possible individualism. The person that is an open structure, open inward and outward, toward himself and toward the other , allows the foundation of a relational ethos, and ethos of the I-Thou, from which emerges the "us?, and a better understanding of the common good.(AU)


Assuntos
Constituição e Estatutos , Empatia , Ética , Psicologia
10.
Memorandum ; 31: 206-217, out. 2016.
Artigo em Espanhol | Index Psicologia - Periódicos | ID: psi-71475

RESUMO

Desde la aproximación fenomenológica que realiza Edith Stein para la comprensión de la estructura óntica y dinamismo de la acción propiamente humana, se puede considerar la empatía como un acto propio de la persona, el cual está presente en la constitución del individuo psicofísico, y es desde donde se establece el dinamismo perfectivo de ésta. Dando lugar así, a la comprensión de la persona como un ser-con-los-demás, desde donde se establecerán las bases para una ética de la persona considerada en su ser relacional, eludiendo cualquier posible individualismo. La persona al ser una estructura abierta, abierta hacia dentro y hacia fuera, hacia sí mismo y hacia el otro, permite la fundamentación de un ethos relacional, del Yo-Tú, del que emerge el nosotros, y portanto una comprensión más acabada del bien común.(AU)


From the phenomenological approach that Edith Stein proposed, for understanding the ontological structure and dynamism of human action, empathy can be considered as an act of the person, which is present in the constitution of the Psycho-physical Individual,and establish the perfective dynamism of the person. Leading to the understanding of the person as a being - with -others, from where establishes the basis of an ethic that consider the individual as a relational being, avoiding any possible individualism. The person that is an open structure, open inward and outward, toward himself and toward the other, allows the foundation of a relational ethos, and ethos of the I-Thou, from which emerges the 'us‟, and a better understanding of the common good.(AU)


Assuntos
Psicologia
11.
Elife ; 52016 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-27296645

RESUMO

Artemisinin-based therapies are the only effective treatment for malaria, the most devastating disease in human history. To meet the growing demand for artemisinin and make it accessible to the poorest, an inexpensive and rapidly scalable production platform is urgently needed. Here we have developed a new synthetic biology approach, combinatorial supertransformation of transplastomic recipient lines (COSTREL), and applied it to introduce the complete pathway for artemisinic acid, the precursor of artemisinin, into the high-biomass crop tobacco. We first introduced the core pathway of artemisinic acid biosynthesis into the chloroplast genome. The transplastomic plants were then combinatorially supertransformed with cassettes for all additional enzymes known to affect flux through the artemisinin pathway. By screening large populations of COSTREL lines, we isolated plants that produce more than 120 milligram artemisinic acid per kilogram biomass. Our work provides an efficient strategy for engineering complex biochemical pathways into plants and optimizing the metabolic output.


Assuntos
Engenharia Metabólica/métodos , Redes e Vias Metabólicas/genética , Biologia Molecular/métodos , Nicotiana/metabolismo , Plantas Medicinais/metabolismo , Biologia Sintética/métodos , Antimaláricos/metabolismo , Artemisininas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Medicinais/genética , Nicotiana/genética
12.
Obes Surg ; 26(11): 2555-2561, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27079191

RESUMO

BACKGROUND: Portomesenteric vein thrombosis (PMVT) is a rare but severe complication after laparoscopic bariatric surgery, with potentially serious consequences. We aimed to describe the incidence, clinical features, management, outcome, and midterm follow-up in patients with PMVT after laparoscopic sleeve gastrectomy (LSG). METHODS: This retrospective and descriptive study included patients who underwent LSG between November 2009 and July 2015 and developed PMVT. The following data were analyzed: age, gender, body mass index (BMI), thrombosis risk factors, surgical technique, thromboembolic prophylaxis, primary surgery outcomes, clinical features, treatment, thrombophilia testing results, and follow-up findings, including imaging and endoscopic findings. RESULTS: A total of 1236 patients underwent LSG, and 5 (0.4 %) developed PMVT. The mean age was 34.4 years, and 3 patients were women. The mean BMI was 38.5 kg/m2. Two patients had received hormonal contraceptive treatment. Four patients had a history of smoking. All of the patients received anticoagulant treatment, and none required surgery. The mean hospitalization duration was 7.6 days. Two patients showed complete recanalization. One patient showed portal cavernomatosis on delayed images. Two patients had a positive thrombophilia test. No portal hypertension endoscopic findings were observed. CONCLUSIONS: PMVT is a rare complication, for which smoking was identified as a predominant risk factor. Early diagnosis and prompt anticoagulant therapy could lead to a dramatic decrease in the incidence of intestinal infarction, mortality, and extrahepatic portal hypertension in the near future. However, careful follow-up is necessary to evaluate the impact of PMVT on long-term patient outcomes.


Assuntos
Anticoagulantes/uso terapêutico , Gastrectomia/efeitos adversos , Isquemia Mesentérica/terapia , Obesidade Mórbida/cirurgia , Veia Porta , Trombose Venosa/etiologia , Adulto , Feminino , Seguimentos , Gastrectomia/métodos , Humanos , Incidência , Laparoscopia , Masculino , Isquemia Mesentérica/etiologia , Estudos Retrospectivos , Fatores de Risco , Trombose Venosa/terapia
13.
PLoS One ; 8(3): e58144, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23555569

RESUMO

Plant carotenoids are synthesized and accumulated in plastids through a highly regulated pathway. Lycopene ß-cyclase (LCYB) is a key enzyme involved directly in the synthesis of α-carotene and ß-carotene through the cyclization of lycopene. Carotenoids are produced in both carrot (Daucus carota) leaves and reserve roots, and high amounts of α-carotene and ß-carotene accumulate in the latter. In some plant models, the presence of different isoforms of carotenogenic genes is associated with an organ-specific function. D. carota harbors two Lcyb genes, of which DcLcyb1 is expressed in leaves and storage roots during carrot development, correlating with an increase in carotenoid levels. In this work, we show that DcLCYB1 is localized in the plastid and that it is a functional enzyme, as demonstrated by heterologous complementation in Escherichia coli and over expression and post transcriptional gene silencing in carrot. Transgenic plants with higher or reduced levels of DcLcyb1 had incremented or reduced levels of chlorophyll, total carotenoids and ß-carotene in leaves and in the storage roots, respectively. In addition, changes in the expression of DcLcyb1 are accompanied by a modulation in the expression of key endogenous carotenogenic genes. Our results indicate that DcLcyb1 does not possess an organ specific function and modulate carotenoid gene expression and accumulation in carrot leaves and storage roots.


Assuntos
Daucus carota/enzimologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Liases Intramoleculares/biossíntese , Folhas de Planta/enzimologia , Proteínas de Plantas/biossíntese , Raízes de Plantas/enzimologia , Daucus carota/genética , Liases Intramoleculares/genética , Folhas de Planta/genética , Proteínas de Plantas/genética , Raízes de Plantas/genética , beta Caroteno/biossíntese , beta Caroteno/genética
14.
Plant Mol Biol ; 79(1-2): 47-59, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22427026

RESUMO

Carrot is an important nutritional crop due to the high levels of pro-vitamin A carotenoids (ß-carotene and, to a lower extent, α-carotene) that accumulate in its storage root during secondary growth. In this work we show that in carrots, contrary to that reported for aerial organs of other plant species, light has a profound effect on root development by inhibiting root thickening, preventing the differentiation of chromoplasts and eventually repressing the expression of most genes required for the biosynthesis of ß-carotene and α-carotene and to a lesser extent genes for xanthophylls and apocarotenoids biosynthesis. We observed a correlation in the carotenoid profile and the patterns of gene expression during the development of root segments grown either in the light or in the dark, which suggests a transcriptional regulation for carotenoid synthesis during carrot root development. Furthermore, our work supports the conclusion that the differentiation of chromoplasts coincides with carotenoid accumulation during the later stages of development of underground storage roots.


Assuntos
Carotenoides/genética , Daucus carota/genética , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Luz , Organogênese/efeitos da radiação , Raízes de Plantas/genética , Plastídeos/efeitos da radiação , Carotenoides/biossíntese , Carotenoides/química , Cloroplastos/metabolismo , Cloroplastos/efeitos da radiação , Escuridão , Daucus carota/crescimento & desenvolvimento , Daucus carota/efeitos da radiação , Regulação da Expressão Gênica no Desenvolvimento/efeitos da radiação , Microscopia de Fluorescência , Especificidade de Órgãos/genética , Especificidade de Órgãos/efeitos da radiação , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/efeitos da radiação , Plastídeos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
15.
Biol Res ; 41(3): 289-301, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19399342

RESUMO

Carotenoids are synthesized in prokaryotic and eukaryotic organisms. In plants and algae, these lipophilic molecules possess antioxidant properties acting as reactive oxygen species scavengers and exert functional roles in hormone synthesis, photosynthesis, photomorphogenesis and in photoprotection. During the past decade almost all carotenogenic genes have been identified as a result of molecular, genetic and biochemical approaches utilizing Arabidopsis thaliana as the model system. Studies carried out in leaves and fruits of A. thaliana and tomato determined that light regulates carotenoid biosynthesis preferentially through the modulation of carotenogenic gene transcription. In this work we showed for the first time that light induces accumulation of psy1, pds and zds2 transcripts in leaves of Daucus carota (carrot), a novel plant model. In addition, modified roots of carrots exposed to light accumulate zds1, whereas the pds gene is highly repressed, suggesting that some carotenogenic genes, which are expressed in roots, are regulated by light. Additionally, light negatively regulates the development of the modified carrot root in a reversible manner. Therefore, this suggests that light affects normal growth and carotenogenic gene expression in the modified root of carrot plants. The molecular insight gained into the light-regulated expression of carotenoid genes in this and other model systems will facilitate our understanding of the regulation of carotenoid biosynthesis to improve the prospects for the metabolic engineering of carotenoid production in plants.


Assuntos
Carotenoides/genética , Daucus carota/genética , Regulação da Expressão Gênica de Plantas/genética , Luz , Modelos Genéticos , Carotenoides/biossíntese , Daucus carota/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Biol. Res ; 41(3): 289-301, 2008. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-511919

RESUMO

Carotenoids are synthesized in prokaryotic and eukaryotic organisms. In plants and algae, these lipophilic molecules possess antioxidant properties acting as reactive oxygen species scavengers and exert functional roles in hormone synthesis, photosynthesis, photomorphogenesis and in photoprotection. During the past decade almost all carotenogenic genes have been identified as a result of molecular, genetic and biochemical approaches utilizing Arabidopsis thaliana as the model system. Studies carried out in leaves and fruits of A. thaliana and tomato determined that light regulates carotenoid biosynthesis preferentially through the modulation of carotenogenic gene transcription. In this work we showed for the first time that light induces accumulation of psy 1, pds and zds2 transcripts in leaves of Daucus carota (carrot), a novel plant model. In addition, modified roots of carrots exposed to light accumulate zdsl, whereas the pds gene is highly repressed, suggesting that some carotenogenic genes, which are expressed in roots, are regulated by light. Additionally, light negatively regulates the development of the modified carrot root in a reversible manner. Therefore, this suggests that light affects normal growth and carotenogenic gene expression in the modified root of carrot plants. The molecular insight gained into the light-regulated expression of carotenoid genes in this and other model systems will facilitate our understanding of the regulation of carotenoid biosynthesis to improve the prospects for the metabolic engineering of carotenoid production in plants.


Assuntos
Carotenoides/genética , Daucus carota/genética , Regulação da Expressão Gênica de Plantas/genética , Luz , Modelos Genéticos , Carotenoides/biossíntese , Daucus carota/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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