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1.
Hum Reprod ; 38(4): 560-568, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36806843

RESUMEN

STUDY QUESTION: In women with threatened miscarriage, does progesterone supplementation until the completion of the first trimester of pregnancy increase the probability of live birth? SUMMARY ANSWER: In women with threatened miscarriage, 400 mg vaginal progesterone nightly, from onset of bleeding until 12 weeks, did not increase live birth rates. WHAT IS KNOWN ALREADY: Limited evidence has indicated that vaginal micronized progesterone may make little or no difference to the live birth rate when compared with placebo in women with threatened miscarriage. Subgroup analysis of one recent randomized trial reported that in women with bleeding and at least one previous miscarriage, progesterone might be of benefit. STUDY DESIGN, SIZE, DURATION: We performed a randomized, double-blinded, placebo-controlled trial between February 2012 and April 2019. Eligible pregnant women under 10 weeks gestation, experiencing a threatened miscarriage as apparent from vaginal bleeding were randomized into two groups in a 1:1 ratio: the intervention group received 400 mg progesterone as vaginal pessaries, the control group received placebo vaginal pessaries, both until 12 weeks gestation. The primary endpoint was live birth. We planned to randomize 386 women (193 per group). The study was stopped at a planned interim analysis for futility after randomization of 278 women. PARTICIPANTS/MATERIALS, SETTING, METHODS: This trial was conducted at the Mater Mothers' Hospital, a tertiary centre for maternity care in South Brisbane, Queensland, Australia. We randomized 139 women to the intervention group and 139 women to the placebo group. Primary outcome data were available for 136 women in the intervention group and 133 women in the placebo group. MAIN RESULTS AND THE ROLE OF CHANCE: The live birth rates were 82.4% (112/136) and 84.2% (112/133) in the intervention group and placebo group, respectively (risk ratio (RR) 0.98, 95% CI 0.88 to 1.09; risk difference -0.02, 95% CI -0.11 to 0.07; P = 0.683). Among women with at least one previous miscarriage, live birth rates were 80.6% (54/67) and 84.4% (65/77) (RR 0.95, 95% CI 0.82-1.11; P = 0.550). No significant effect was seen from progesterone in women with two (RR 1.28, 95% CI 0.96-1.72; P = 0.096) or more (RR 0.79, 95% CI 0.53-1.19; P = 0.267) previous miscarriages. Preterm birth rates were 12.9% and 9.3%, respectively (RR 1.38; 95% CI 0.69 to 2.78; P = 0.361). Median birth weight was 3310 vs 3300 g (P = 0.992). There were also no other significant differences in obstetric and perinatal outcomes. LIMITATIONS, REASONS FOR CAUTION: Our study was single centre and did not reach the planned sample size because it was stopped prematurely at an interim analysis. WIDER IMPLICATIONS OF THE FINDINGS: We did not find evidence supporting the treatment effect of vaginal progesterone in women with threatened miscarriage. Progesterone in this setting should not be routinely used for threatened miscarriage. The treatment effect in women with threatened miscarriage after previous miscarriages warrants further research. STUDY FUNDING/COMPETING INTEREST(S): Mothers' and babies Golden Casket Clinical Fellowship (L.A.M.). Progesterone and placebo pessaries were provided by Perrigo Australia.B.W.J.M. reports grants from NHMRC, personal fees from ObsEva, personal fees from Merck KGaA, personal fees from Guerbet, personal fees from iGenomix, outside the submitted work. TRIAL REGISTRATION NUMBER: ACTRN12611000405910. TRIAL REGISTRATION DATE: 19 April 2011. DATE OF FIRST PATIENT'S ENROLMENT: 06 February 2012.


Asunto(s)
Aborto Espontáneo , Amenaza de Aborto , Servicios de Salud Materna , Nacimiento Prematuro , Embarazo , Femenino , Recién Nacido , Humanos , Progesterona/uso terapéutico , Aborto Espontáneo/epidemiología , Aborto Espontáneo/tratamiento farmacológico , Amenaza de Aborto/tratamiento farmacológico , Nacimiento Prematuro/prevención & control , Índice de Embarazo
2.
Methods Mol Biol ; 2306: 105-121, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33954943

RESUMEN

Fatty acids are an essential structural and energy storage component of cells and hence there is much interest in their metabolism, requiring identification and quantification with readily available instrumentation, such as GC-MS. Fatty acid methyl esters (FAMEs) can be generated and extracted directly from biological tissue, in a one-pot process, and following high resolution GC, their respective chain length, degrees of unsaturation, and other functionalities can be readily identified using EI-MS. Defining the positions of the double bonds in the alkyl chain requires conversion of the FAMEs into their respective dimethyloxazoline (DMOX) derivatives. Following EI, this derivative allows charge retention on the heterocycle, and concomitant charge remote fragmentation of the alkyl chain to yield key double bond position identifying ions. The protocols described herein have been applied to the identification and quantification of fatty acids harvested from microalgae grown to produce biofuels and to the screening of salt tolerant Arabidopsis mutants.


Asunto(s)
Arabidopsis/química , Ácidos Grasos/aislamiento & purificación , Lipidómica/métodos , Microalgas/química , Biología Computacional , Esterificación , Ácidos Grasos/química , Cromatografía de Gases y Espectrometría de Masas , Estructura Molecular , Oxazoles/química , Hojas de la Planta/química , Raíces de Plantas/química , Tallos de la Planta/química , Programas Informáticos
4.
Front Microbiol ; 7: 475, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27092129

RESUMEN

Interest in the production of carbon commodities from photosynthetically fixed CO2 has focused attention on cyanobacteria as a target for metabolic engineering and pathway investigation. We investigated the redirection of carbon flux in the model cyanobacterial species, Synechococcus elongatus PCC 7942, under nitrogen deprivation, for optimized production of the industrially desirable compound, pyruvate. Under nitrogen limited conditions, excess carbon is naturally stored as the multi-branched polysaccharide, glycogen, but a block in glycogen synthesis, via knockout mutation in the gene encoding ADP-glucose pyrophosphorylase (glgC), results in the accumulation of the organic acids, pyruvate and 2-oxoglutarate, as overflow excretions into the extracellular media. The ΔglgC strain, under 48 h of N-deprivation was shown to excrete pyruvate for the first time in this strain. Additionally, by increasing culture pH, to pH 10, it was possible to substantially elevate excretion of pyruvate, suggesting the involvement of an unknown substrate/proton symporter for export. The ΔglgC mutant was also engineered to express foreign transporters for glucose and sucrose, and then grown photomixotrophically with exogenous organic carbon supply, as added 5 mM glucose or sucrose during N- deprivation. Under these conditions we observed a fourfold increase in extracellular pyruvate excretion when glucose was added, and a smaller increase with added sucrose. Although the magnitude of pyruvate excretion did not correlate with the capacity of the ΔglgC strain for bicarbonate-dependent photosynthetic O2 evolution, or with light intensity, there was, however, a positive correlation observed between the density of the starter culture prior to N-deprivation and the final extracellular pyruvate concentration. The factors that contribute to enhancement of pyruvate excretion are discussed, as well as consideration of whether the source of carbon for pyruvate excretion might be derived from photosynthetic CO2 fixation or from remobilisation of existing carbon stores.

5.
Bioresour Technol ; 127: 441-7, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23138068

RESUMEN

This study investigated the changes in the fatty acid content and composition in the nitrogen-starved Chlamydomonas reinhardtii starchless mutant, BAF-J5, grown at different temperatures. The optimal temperature for vegetative growth under nitrogen sufficient conditions was found to be 32 °C. Shifting temperature from 25 to 32 °C, in conjunction with nitrogen starvation, resulted in BAF-J5 storing the maximum quantity of fatty acid (76% of dry cell weight). Shifting to temperatures lower than 25 °C, reduced the total amount of stored fatty acid content and increased the level of desaturation in the fatty acids. The optimal fatty acid composition for biodiesel was at 32 °C. This study demonstrates how a critical environmental factor, such as temperature, can modulate the amount and composition of fatty acids under nitrogen deprivation and reduce the requirement for costly refining of biofuels.


Asunto(s)
Biocombustibles/análisis , Chlamydomonas reinhardtii/metabolismo , Ácidos Grasos/metabolismo , Nitrógeno/deficiencia , Temperatura , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía Infrarroja por Transformada de Fourier
6.
Bioresour Technol ; 102(3): 3343-51, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21146403

RESUMEN

The Chlamydomonas reinhardtii starch-less mutant, BAF-J5, was found to store lipids up to 65% of dry cell weight when grown photoheterotrophically and subjected to nitrogen starvation. Fourier transform infrared spectroscopy was used as a high-throughput method for semi-quantitative measurements of protein, carbohydrate and lipid content. The fatty acids of wild-type and starch mutants were identified and quantified by gas chromatography mass spectrometry. C. reinhardtii starch mutants, BAF-J5 and I7, produce significantly elevated levels of 16:0, 18:1(Δ9), 18:2(Δ9,12) and 18:3(Δ9,12,15) fatty acids. Long-chain saturated, mono- and polyunsaturated fatty acids were found under nitrogen starvation. Oleosin-like and caleosin-like genes were identified in the C. reinhardtii genome. However, proteomic analysis of isolated lipid bodies only identified a key lipid droplet associated protein. This study shows it is possible to manipulate algal biosynthetic pathways to produce high levels of lipid that may be suitable for conversion to liquid fuels.


Asunto(s)
Chlamydomonas reinhardtii/metabolismo , Ácidos Grasos/metabolismo , Nitrógeno/metabolismo , Transducción de Señal/fisiología
7.
Neurochem Int ; 50(2): 450-9, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17141922

RESUMEN

It is widely accepted that the chronic use of alcohol induces metabolic abnormalities and neuronal damage in the brain, which can lead to cognitive dysfunction. Neuroimaging studies reveal that alcohol-induced brain damage is region specific and prominent damage has been observed in both gray and white matter of the prefrontal cortex, and a wide range of white matter structures including the corpus callosum. Molecular mechanisms underlying these structural changes are largely unknown. Using proteomics we have analysed the changes in protein expression in the splenium of the corpus callosum in two different alcoholic groups. Protein extracts from splenium of 22 human brains (nine controls, seven uncomplicated alcoholics and six complicated alcoholics with hepatic cirrhosis-designated complicated) were separated using two-dimensional gel electrophorosis. Image analysis revealed that there were significant alterations in protein expression for 25 protein spots in the uncomplicated alcoholic group and 45 in the complicated group compared to control (P<0.05; ANOVA). In a total of 72 spots (identified as 36 proteins), 15 (identified as 14 proteins) spots overlapped between two alcoholic groups. Another 32 protein spots (26 different proteins) were identified only in the complicated alcoholics. It is therefore possible that these 26 proteins in the complicated group are likely to be the results of hepatic compromise. When compared with our previous data of white matter from the prefrontal cortex in alcoholics, large numbers of identified proteins in the splenium are different. This suggests that there may be different mechanisms causing alcohol-induced brain damage in different regions of the white matter. Our data also indicate the importance of other pathways including oxidative stress, lipid peroxidation and apoptosis as potential causes of alcohol-induced brain damage.


Asunto(s)
Alcoholismo/metabolismo , Cuerpo Calloso/metabolismo , Proteínas del Tejido Nervioso/biosíntesis , Proteómica , Anciano , Anciano de 80 o más Años , Cuerpo Calloso/efectos de los fármacos , Proteínas del Citoesqueleto/metabolismo , Bases de Datos Genéticas , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Concentración de Iones de Hidrógeno , Procesamiento de Imagen Asistido por Computador , Técnicas In Vitro , Cirrosis Hepática/metabolismo , Masculino , Espectrometría de Masas , Persona de Mediana Edad
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