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1.
ESMO Open ; 9(5): 102974, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38796284

RESUMEN

The European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with early breast cancer were updated and published online in 2023, and adapted, according to previously established standard methodology, to produce the Pan-Asian adapted (PAGA) ESMO consensus guidelines for the management of Asian patients with early breast cancer. The adapted guidelines presented in this manuscript represent the consensus opinions reached by a panel of Asian experts in the treatment of patients with breast cancer representing the oncological societies of China (CSCO), Indonesia (ISHMO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), the Philippines (PSMO), Singapore (SSO), Taiwan (TOS) and Thailand (TSCO), co-ordinated by ESMO and KSMO. The voting was based on scientific evidence and was independent of the current treatment practices, drug access restrictions and reimbursement decisions in the different Asian regions represented by the 10 oncological societies. The latter are discussed separately in the manuscript. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with early breast cancer across the different regions of Asia, drawing on the evidence provided by both Western and Asian trials, whilst respecting the differences in screening practices, molecular profiling, as well as the age and stage at presentation. Attention is drawn to the disparity in the drug approvals and reimbursement strategies, between the different regions of Asia.


Asunto(s)
Neoplasias de la Mama , Humanos , Neoplasias de la Mama/terapia , Neoplasias de la Mama/diagnóstico , Femenino , Asia/epidemiología , Oncología Médica/normas , Guías de Práctica Clínica como Asunto , Estadificación de Neoplasias
2.
Sci Rep ; 14(1): 9113, 2024 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-38643179

RESUMEN

While several effective therapies for critically ill patients with COVID-19 have been identified in large, well-conducted trials, the mechanisms underlying these therapies have not been investigated in depth. Our aim is to investigate the association between various immunosuppressive therapies (corticosteroids, tocilizumab and anakinra) and the change in endothelial host response over time in critically ill COVID-19 patients. We conducted a pre-specified multicenter post-hoc analysis in a Dutch cohort of COVID-19 patients admitted to the ICU between March 2020 and September 2021 due to hypoxemic respiratory failure. A panel of 18 immune response biomarkers in the complement, coagulation and endothelial function domains were measured using ELISA or Luminex. Biomarkers were measured on day 0-1, day 2-4 and day 6-8 after start of COVID-19 treatment. Patients were categorized into four treatment groups: no immunomodulatory treatment, corticosteroids, anakinra plus corticosteroids, or tocilizumab plus corticosteroids. The association between treatment group and the change in concentrations of biomarkers was estimated with linear mixed-effects models, using no immunomodulatory treatment as reference group. 109 patients with a median age of 62 years [IQR 54-70] of whom 72% (n = 78) was male, were included in this analysis. Both anakinra plus corticosteroids (n = 22) and tocilizumab plus corticosteroids (n = 38) were associated with an increase in angiopoietin-1 compared to no immune modulator (n = 23) (beta of 0.033 [0.002-0.064] and 0.041 [0.013-0.070] per day, respectively). These treatments, as well as corticosteroids alone (n = 26), were further associated with a decrease in the ratio of angiopoietin-2/angiopoietin-1 (beta of 0.071 [0.034-0.107], 0.060 [0.030-0.091] and 0.043 [0.001-0.085] per day, respectively). Anakinra plus corticosteroids and tocilizumab plus corticosteroids were associated with a decrease in concentrations of complement complex 5b-9 compared to no immunomodulatory treatment (0.038 [0.006-0.071] and 0.023 [0.000-0.047], respectively). Currently established treatments for critically ill COVID-19 patients are associated with a change in biomarkers of the angiopoietin and complement pathways, possibly indicating a role for stability of the endothelium. These results increase the understanding of the mechanisms of interventions and are possibly useful for stratification of patients with other inflammatory conditions which may potentially benefit from these treatments.


Asunto(s)
COVID-19 , Humanos , Masculino , Persona de Mediana Edad , Anciano , Angiopoyetina 1 , SARS-CoV-2 , Proteína Antagonista del Receptor de Interleucina 1/uso terapéutico , Enfermedad Crítica/terapia , Tratamiento Farmacológico de COVID-19 , Corticoesteroides/uso terapéutico , Terapia de Inmunosupresión , Biomarcadores
3.
ESMO Open ; 8(3): 101541, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37178669

RESUMEN

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, staging and treatment of patients with metastatic breast cancer (MBC) was published in 2021. A special, hybrid guidelines meeting was convened by ESMO and the Korean Society of Medical Oncology (KSMO) in collaboration with nine other Asian national oncology societies in May 2022 in order to adapt the ESMO 2021 guidelines to take into account the differences associated with the treatment of MBC in Asia. These guidelines represent the consensus opinions reached by a panel of Asian experts in the treatment of patients with MBC representing the oncological societies of China (CSCO), India (ISMPO), Indonesia (ISHMO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), the Philippines (PSMO), Singapore (SSO), Taiwan (TOS) and Thailand (TSCO). The voting was based on the best available scientific evidence and was independent of drug access or practice restrictions in the different Asian countries. The latter were discussed when appropriate. The aim of these guidelines is to provide guidance for the harmonisation of the management of patients with MBC across the different regions of Asia, drawing from data provided by global and Asian trials whilst at the same time integrating the differences in genetics, demographics and scientific evidence, together with restricted access to certain therapeutic strategies.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/terapia , Asia , India , Sociedades Médicas , Oncología Médica
4.
J Eur Acad Dermatol Venereol ; 28(11): 1475-9, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24236446

RESUMEN

BACKGROUND: Vitiligo is an acquired depigmentation disorder of melanocytes. Recently, some clinical reports have suggested that proton pump inhibitors (PPIs) may worsen vitiligo, but their effects on melanocytes have yet to be elucidated. OBJECTIVE: We investigated the effect of PPIs on melanogenesis in vivo and in vitro. METHODS: We examined the effect of PPIs on melanogenesis in B16 murine melanoma cells by measuring melanin content and tyrosinase (TYR) activity. TYR and tyrosinase-related protein-1 (TRP-1) were monitored by western blotting. Finally, a PPI was applied to zebrafish embryos to investigate its in vivo effect on pigmentation. RESULTS: In agreement with our clinical experience of worsened vitiligo after PPI treatment, PPIs decreased both melanin content and TYR activity. Western blotting showed that PPIs decreased TYR and TRP-1 protein levels. In the zebrafish test, PPIs inhibited body pigmentation in a dose-dependent manner. CONCLUSION: These results suggest that the functional inhibition of melanization by PPIs may induce or aggravate vitiligo lesions in genetically predisposed patients.


Asunto(s)
Úlcera Duodenal/tratamiento farmacológico , Reflujo Laringofaríngeo/tratamiento farmacológico , Melaninas/metabolismo , Inhibidores de la Bomba de Protones/efectos adversos , Inhibidores de la Bomba de Protones/uso terapéutico , Vitíligo/diagnóstico , Vitíligo/etiología , Animales , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Técnicas In Vitro , Interferón Tipo I/metabolismo , Masculino , Melanocitos/efectos de los fármacos , Melanocitos/metabolismo , Melanocitos/patología , Melanoma/metabolismo , Melanoma/patología , Ratones , Persona de Mediana Edad , Modelos Animales , Monofenol Monooxigenasa/metabolismo , Pigmentación , Proteínas Gestacionales/metabolismo , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Pez Cebra
5.
Med J Malaysia ; 68(5): 415-23, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24632872

RESUMEN

No abstract available.

6.
Anaesth Intensive Care ; 40(5): 795-802, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22934861

RESUMEN

In this randomised prospective study we aimed to evaluate whether preoperative anaesthetic education delivered to children on the day of surgery reduces anxiety behaviour during induction of anaesthesia. One hundred children, six to 15 years of age, undergoing general anaesthesia for ambulatory surgery were allocated at random to a preoperative education group (n=50) or a control group (n=50). The main outcomes were behaviour score, self-reporting of satisfaction score and identification of the stage when children felt most fearful. Data from all 100 participants were analysed. There was no difference in behaviour score at induction or satisfaction score between the groups. Eighteen percent in the intervention group reported no fear preoperatively vs 10% in the control group. Intravenous induction failed in nine out of 38 children in the intervention group (23.7%) compared to five out of 40 in the control group (12.5%). When intravenous induction failed, eight out of nine (89%) of the intervention group remained co-operative during gas induction compared to two out of five (40%) of the control group. Preoperative education delivered on the day of surgery did not reduce anxiety behaviour in children during intravenous induction of anaesthesia, but did reduce anxiety during subsequent inhalational induction.


Asunto(s)
Anestesia Intravenosa/psicología , Ansiedad/prevención & control , Conducta Infantil , Miedo , Educación del Paciente como Asunto , Niño , Método Doble Ciego , Femenino , Humanos , Masculino , Periodo Preoperatorio , Estudios Prospectivos
7.
Ann R Coll Surg Engl ; 93(7): 562; author reply 562, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22004652
8.
J Plast Reconstr Aesthet Surg ; 59(10): 1073-5, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16996431

RESUMEN

Old and frail patients with advance breast malignancy require mastectomy which often results in large defects requiring soft tissue cover. We present three cases of large fasciocutaneous perforator based V-Y advancement flaps for reconstruction of large post-mastectomy wounds in older patients with large tumours. This technique reduces the morbidity of patients who have severe co-existing morbidity factor in addition to the advance breast disease.


Asunto(s)
Mamoplastia/métodos , Mastectomía , Colgajos Quirúrgicos , Anciano de 80 o más Años , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/cirugía , Femenino , Anciano Frágil , Humanos
10.
J Nutr ; 135(3): 513-8, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15735086

RESUMEN

Yeast single-cell protein (SCP) is a high-nutrient feed substitute. This study evaluates the dual applications of a novel recombinant Pichia pastoris SMD1168H (SMD) yeast, expressing a tilapia vitellogenin protein (rVtg), as an SCP diet for Artemia and the first-feeding fish larvae. Instar II Artemia fed rVtg, rVtg precultured in 5% fish oil (rVtg-FO), Saccharomyces cerevisiae (SC), or native SMD had greater lipid contents (P < 0.05) than the freshly hatched. Lipid deposition in the Artemia fed rVtg or rVtg-FO was greater (P < 0.05) than in those fed SMD or SC. Diet-induced accumulation of low levels of docosahexaenoic acid [22:6(n-3)] was detected only in Artemia fed the rVtg-based diets. Tilapia (Oreochromis mossambicus) larvae were fed solely yeast diets singly or in combination (d 3-22), or a staggered regimen of yeast (d 3-12) followed by unenriched or yeast-enriched Artemia (d 13-22). The larvae fed rVtg for 22 d increased in length and weight (P < 0.05), whereas those fed SC or SMD suffered growth suppression and high mortality. Such adverse consequences were ameliorated when 50% of SC was substituted with rVtg. The larvae prefed rVtg followed by a dietary switch to Artemia preenriched for 48 h with rVtg or rVtg-FO were greatest in length, had the highest weight gain, and lived the longest. Besides delivering rVtg protein, essential fatty acids and amino acids, rVtg may have probiotic effects in enhancing larval survival. This study suggests the feasibility of using the rVtg yeast as an Artemia booster and an SCP first feed for larvae.


Asunto(s)
Proteínas en la Dieta/farmacología , Crecimiento/efectos de los fármacos , Pichia , Tilapia/crecimiento & desarrollo , Vitelogeninas/farmacología , Animales , Proteínas Fúngicas , Larva , Proteínas Recombinantes/farmacología , Saccharomyces cerevisiae , Vitelogeninas/genética
11.
Biotechnol Bioeng ; 85(3): 330-9, 2004 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-14748089

RESUMEN

Vitellogenin (Vtg) plays vital roles as precursor to the yolk proteins and as carrier for lipids, carbohydrates, phosphates, metal ions, vitamins, and hormones into the oocytes during the massive deposition of yolk nutrients for subsequent nourishment of the developing embryos. Reproductive success is highly sensitive to the nutritional quality of the broodstock diet, which greatly affects the egg and larval viability. We present a novel strategy for genetically engineering a Pichia pastoris yeast strain that constitutively produces recombinant Vtg (rVtg), for application as an enriched feed. The tilapia Oreochromis aureus Vtg (OaVtg) cDNA (5.3 kb) was cloned into a nonsecretory pGAPZA vector. Clones containing up to 31 copies of glyceraldehyde-3-phosphate dehydrogenase (GAP)-promoter-driven Vtg expression cassettes were isolated. These clones expressed a membrane-associated intracellular rVtg protein of 194 kDa, constituting up to 1.16% of total protein. To facilitate future purification of rVtg, we explored the possibility of secreting rVtg using the native Vtg secretion signal and the alpha-factor secretion signal of Saccharomyces cerevisiae. However, neither signal promoted the secretion of rVtg. The clones maximally expressed rVtg at 23 degrees C, reaching a peak at 22 h in shake flasks and 16 h in a fermentor. The clones exhibited a significant increase in essential amino acids and long-chain polyunsaturated fatty acids, which are important for its application as a high-quality nutrient feed.


Asunto(s)
Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Pichia/genética , Pichia/metabolismo , Ingeniería de Proteínas/métodos , Vitelogeninas/biosíntesis , Vitelogeninas/genética , Aminoácidos Esenciales/biosíntesis , Animales , Clonación Molecular/métodos , Ácidos Grasos Insaturados/biosíntesis , Regiones Promotoras Genéticas/genética , Proteínas Recombinantes/biosíntesis , Tilapia/genética , Tilapia/metabolismo
12.
Singapore Med J ; 44(7): 340-3, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-14620724

RESUMEN

INTRODUCTION: Pre-operative Chest X-ray (CXR) and electrocardiograms (ECG) are routinely ordered locally for patients above a certain age. This study examines the usefulness of such a practice and its clinical impact. METHODS: Prospective audit of 875 consecutive anaesthetic patients over a one-month period, assessing the proportion and impact of abnormal CXR or ECG findings. RESULTS: The proportion of patients with abnormal CXR or ECG increased with worsening ASA status. There was little impact of routine pre-operative CXR and ECG on anaesthetic management. Only 11/324 CXR and 13/375 ECG affected anaesthetic technique or choice of therapeutic procedure. CONCLUSION: Targeted investigations should be performed as indicated by clinical findings rather than on the basis of arbitrary age cut-offs.


Asunto(s)
Pruebas Diagnósticas de Rutina/estadística & datos numéricos , Electrocardiografía/estadística & datos numéricos , Auditoría Médica , Radiografía Torácica/estadística & datos numéricos , Adulto , Humanos , Persona de Mediana Edad
13.
Gene ; 277(1-2): 175-86, 2001 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-11602355

RESUMEN

Vitellogenins (Vtg) are egg-yolk precursor proteins crucial for reproductive success in oviparous animals. We have cloned the first complete cichlid Vtg cDNA from the tilapia fish, Oreochromis aureus. This cDNA has the largest phosvitin (PV) domain amongst piscine Vtgs, being comparable to those of lamprey, Xenopus, and chicken. Thus, the size of PV is independent of the evolutionary advancement of a species. The closer interspecific relationship between O. aureus Vtg1 and Fundulus VtgII than the intraspecific relationship between Fundulus VtgI and II isoforms suggests that teleost ancestors had at least two Vtg isoforms. Contrary to the results of previous phylogenetic inference using Vtgs which indicate that insect lineage is most diverged and nematodes are closer to vertebrate lineage, our results show that nematodes and hexapods form two monophyletic sister groups. Another arthropod taxon, represented by a malacostracan crustacean, Penaeus japonicus, appears to be more closely related to the vertebrates than the hexapods.


Asunto(s)
ADN Complementario/genética , Fosvitina/genética , Tilapia/genética , Vitelogeninas/genética , Secuencia de Aminoácidos , Animales , Secuencia Conservada/genética , ADN Complementario/química , Proteínas del Huevo/genética , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
14.
Can J Anaesth ; 48(6): 570-4, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11444452

RESUMEN

PURPOSE: The study was aimed primarily at comparing the duration of analgesia produced by intrathecal fentanyl 25 microg with sufentanil 5 microg when added to bupivacaine 1.25 mg as the initial component of the combined spinal epidural (CSE) technique in early labour. METHODS: Forty healthy parturients were randomly assigned into two groups to receive either intrathecal sufentanil 5 microg plus bupivacaine 1.25 mg (Group S) or intrathecal fentanyl 25 microg plus bupivacaine 1.25 mg (Group F). Apart from the duration of analgesia, pain scores and side effects were also evaluated. RESULTS: There was no significant difference in the duration of analgesia (mean 109 +/- SD 49 min in Group F vs 118 +/- 54 min in Group S, P=0.9). Group F had a more rapid onset of analgesia (P <0.05) and a higher cephalad block (median T4 vs T7, P <0.05) in the first 30 min after the block. No difference in the side effects was detected. CONCLUSION: Fentanyl 25 microg is a good alternative to sufentanil 5 microg when added to bupivacaine 1.25 mg for early labour analgesia.


Asunto(s)
Analgesia Obstétrica , Analgésicos Opioides , Bupivacaína , Fentanilo , Sufentanilo , Adulto , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/efectos adversos , Bupivacaína/administración & dosificación , Bupivacaína/efectos adversos , Femenino , Fentanilo/administración & dosificación , Fentanilo/efectos adversos , Humanos , Inyecciones Espinales , Dimensión del Dolor , Embarazo , Sufentanilo/administración & dosificación , Sufentanilo/efectos adversos
15.
Biochem Biophys Res Commun ; 269(2): 574-9, 2000 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-10708596

RESUMEN

Effects of the aminoglycoside spectinomycin on the self-splicing of primary transcripts of the phage T4 thymidylate synthase gene (td) have been investigated. The kinetic analysis demonstrated that spectinomycin acts as a mixed noncompetitive inhibitor for the td intron RNA with a K(i) of 7.2 mM. Increasing the spectinomycin concentration raised the K(m) values with the corresponding decrease of V(max) and k(cat) values. The specificity of the splicing inhibition by spectinomycin is due to changes in both K(m) and k(cat). The splicing inhibition by spectinomycin is dependent on pH changes and Mg(2+) concentration, indicating electrostatic interactions with the intron RNA. It has been proposed that the key structural features in spectinomycin responsible for the inhibition of splicing may be the hydroxyl groups on the antibiotic.


Asunto(s)
Intrones/efectos de los fármacos , Empalme del ARN/efectos de los fármacos , Espectinomicina/farmacología , Guanosina Trifosfato/farmacología , Concentración de Iones de Hidrógeno , Cinética , Magnesio/farmacología
16.
Ann Acad Med Singap ; 28(4): 529-33, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10561767

RESUMEN

Magnetic resonance (MR) imaging of brain metastases relies on the neovascularity of metastases and the associated breach of blood-brain barrier manifesting as enhancement on T1-weighted images. There are 2 main strategies to improve the detection of brain metastases. One may increase the dose of gadolinium and increase the signal of the lesion. Alternatively, one may also lower the signal of the background (by magnetisation transfer suppression), in which case the enhancing lesion is rendered more conspicuous without increasing the dose of gadolinium. We aim to compare the efficacy of single-dose conventional spin-echo T1 scans with magnetisation transfer (MT) suppression with triple-dose conventional spin-echo T1 scans in the detection of brain metastases in 18 patients undergoing imaging for brain metastases. An incremental dose technique was employed. After administration of a single dose of gadolinium, MT suppressed T1-weighted scans were obtained, followed by a conventional T1 scan. Two doses of gadolinium were subsequently given, achieving a cumulative triple-dose, and a conventional T1-weighted scan was then performed. We found single-dose MT suppressed and triple-dose scans performed equally well and detected 26 metastatic lesions. They detected 5 (5/26, 19%) more lesions than the conventional single-dose T1 scans. Five (5/21, 24%) questionable lesions on single-dose conventional scans were confidently diagnosed on the single-dose MT suppressed and the triple-dose conventional scan. We conclude that single-dose MT suppressed scans are a cost-effective technique of detecting brain metastases.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/secundario , Medios de Contraste , Gadolinio DTPA , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Encéfalo/patología , Medios de Contraste/administración & dosificación , Relación Dosis-Respuesta a Droga , Estudios de Evaluación como Asunto , Femenino , Gadolinio DTPA/administración & dosificación , Humanos , Inyecciones Intravenosas , Imagen por Resonancia Magnética/instrumentación , Masculino , Persona de Mediana Edad
17.
J Nucl Med ; 40(8): 30N-32N, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10450671
18.
Cell Mol Life Sci ; 55(4): 668-78, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10357235

RESUMEN

Twelve cosmids containing sequences resembling genes encoding members of the 70-kDa heat-shock protein family, HSP70. have been isolated from Fugu rubripes. They can be broadly divided into three groups of overlapping cosmids. Restriction analysis and sequencing of one set of five cosmids have revealed five intronless Fugu HSP70 genes spanning 42 kb, arranged in a combined head-to-head, tail-to-tail and head-to-tail orientation. The levels of DNA and amino acid identity are very high with respect to one another, and are most similar to HSP70 sequences linked to the major histocompatibility complex (MHC) region in other species. Putative heat-shock consensus elements are identified. Non-HSP70 sequences with homology to known genes have been found physically linked to this Fugu HSP70 cluster: the Drosophila melanogaster SOL gene, the Drosophila melanogaster nemo gene, the Caenorhabditis elegans T17E9.1 gene and the sequence encoding the serine protease domain. The linkage relationships described here so far bear no resemblance to those of HSP70 in other organisms. Convergence of mammalian HSP70 and MHC class I and II loci probably occurred after fish had diverged.


Asunto(s)
Peces/genética , Proteínas HSP70 de Choque Térmico/genética , Familia de Multigenes , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cósmidos , Dermatoglifia del ADN , ADN Complementario , Peces/clasificación , Genes Sobrepuestos , Proteínas HSP70 de Choque Térmico/clasificación , Humanos , Datos de Secuencia Molecular , Mapeo Restrictivo , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Factores de Tiempo
20.
Mol Cell Endocrinol ; 146(1-2): 103-20, 1998 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-10022768

RESUMEN

The Oreochromis aureus vitellogenin, OaVtg, gene spans 9 kb and contains 34 exons. Its transcription start site is located 15 bp upstream of the translational start codon. Although the OaVtg promoter has a nonconsensus TATA, transient transfection assay showed that this promoter is capable of driving basal transcription. Two imperfect estrogen response elements: EREp (proximal) and EREd (distal) are located in the promoter at - 532 and - 1352, respectively. In competition gel mobility-shift assays, only EREp exhibited specific binding of the recombinant estrogen receptor protein, GST-C/D OaER. Another imperfect ERE (EREexon2) was detected within exon 2 of the OaVtg gene. This is a novel finding for a vitellogenin (Vtg) gene. EREexon2 similarly showed specific recognition of GST-C/D OaER. Both EREp and EREexon2 showed comparable binding affinities as consensus ERE. In transient transfections, the OaVtg promoter, EREp and EREd elicited significant increase in estrogen-dependent synthesis of CAT protein. Hence, we propose that the non-consensus OaVtg EREs contribute to the estrogen-dependent regulation of the OaVtg gene in vivo.


Asunto(s)
Estrógenos/farmacología , Regiones Promotoras Genéticas , Tilapia/genética , Vitelogeninas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cloranfenicol O-Acetiltransferasa/genética , Escherichia coli/genética , Exones , Femenino , Expresión Génica , Intrones , Datos de Secuencia Molecular , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Proteínas Recombinantes/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos , Elementos de Respuesta , Transcripción Genética , Vitelogeninas/química
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