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M Legge

Publications and source records attributed to M Legge.

At least 37 records · Page 2Linked to original sources
PubMed1991

Oocyte and zygote zona pellucida lectin binding in BALB/cBy and C57BL/6By mice and their F1 hybrids.

Zona pellucida intact oocytes and zygotes from two inbred strains of mice (BALB/cByEss and C57BL/6ByEss) and their F1 hybrids were reacted with a lectin panel (ConA, WGA, sWGA, PNA, UEA I, LTA, BSB4, DBA, PHA-P, LPA, and LFA). No major differences were observed between groups of mice for the majority of the lectin binding patterns. However, oocytes from BALB/cByEss and the F1 (C57BL/6ByxBALB/cBy) gave identical binding patterns for PNA. Following fertilization BALB/cByEss and the F1 (C57BL/6ByxBALB/cBy) bound UEAI and LTA more strongly, but the other two groups of mice demonstrated identical weaker binding of UEAI and LTA. These results indicate the possible influence of the paternal genotype on zona pellucida formation.

Animals↗
PubMed1991

Free radical scavengers ameliorate the 2-cell block in mouse embryo culture.

Mouse zygotes from a strain combination which fails to undergo cleavage in vitro (the 2-cell block) were cultured in a variety of media, using either low (5%) or normal (20%) oxygen tension in the gas phase. Development beyond the 4-cell stage was only achieved in medium containing serum and with normal oxygen tension. When serum-free medium was supplemented with free radical scavengers, reduced glutathione (1 mM), but not histidine, catalase or superoxide dismutase, development to the morula or blastocyst stage was promoted in 50% of zygotes cultured with normal oxygen tension. These data suggest that the 2-cell block is a consequence, at least in part, of free radical damage incurred by embryos during collection and culture, and that medium supplementation with the radical scavenger, reduced glutathione, can improve embryo development in vitro.

Animals↗
PubMed1990

Mouse zygotes express endogenous lectins.

Cell interactions during mouse development have been shown to involve carbohydrate-containing macromolecules (glycoconjugates). We have therefore used a series of fluorescein-labelled synthetic glycoproteins to determine if mouse oocytes and zygotes also express sugar binding molecules (endogenous lectins) which might participate in such interactions. Unfertilized secondary oocytes did not express endogenous lectins at 4 degrees C but a low level of expression of fucose, mannose, and galactose-binding activity could be detected at 37 degrees C. In contrast, the zygote clearly expressed three classes of endogenous lectins, with preferential binding for i) fucose or mannose, ii) glucose or galactose, and iii) lactose. The expression of these lectins was much reduced at 4 degrees C and maximal binding at 37 degrees C was achieved only after 2 h incubation. We therefore conclude that a low level of endogenous lectin expression in the mouse oocyte is greatly enhanced after fertilisation and that, at both stages, expression, or the detection of expression, is markedly temperature dependent.

Animals↗
PubMed1986

Amniotic fluid gamma-glutamyl transpeptidase activity during the second trimester.

Gamma glutamyl transpeptidase (GGTP) activity was determined in second trimester amniotic fluid taken from normal fetuses and those with fetal abnormalities. GGTP activity decreased with advancing gestation. Increasing meconium contamination correlated with an increase in GGTP activity as did increasing fetal blood contamination. Maternal blood did not affect GGTP activity. Anencephaly did not significantly alter the GGTP activity, however, fetuses with spina bifida had significantly lower activity. Klinefelters and Turners syndromes both had GGTP activity close to the 50th percentile, and two trisomy 21 fetuses had GGTP activity below the 40th percentile. Two trisomy 18 fetuses and two translocation Downs syndromes (46 XY, t (14;21) had GGTP activities considerably lower than the 20th percentile as did a fetus with gastroschisis. Second trimester amniotic fluid GGTP activity may provide an easy preliminary test to screen amniotic fluids for the possibility of certain fetal chromosome abnormalities.

Amniotic Fluid↗
PubMed1985

Second trimester maternal serum alpha-fetoprotein as an indicator of fetal risk.

Serum alpha-fetoprotein levels were raised to 2.0 or more times the median for gestation in 30 of 507 singleton pregnancies after excluding pregnancies complicated by fetal neural tube defects. The serum alpha-fetoprotein levels were significantly more often elevated in pregnancies complicated by prematurity, fetal heart rate abnormalities, delivery of a small for dates infant, a perinatal death and admission of the baby to the neonatal unit. While the predictive value of an elevated serum alpha-fetoprotein was 76% for abnormal outcomes in general it ranged between only 16% and 46% for specific abnormalities. The usefulness of this assay relates only to its ability to predict an abnormal outcome when performed during the second trimester.

Apgar Score↗
PubMed1984

Maternal serum alpha 1-antitrypsin concentrations in normotensive and hypertensive pregnancies.

Maternal serum alpha 1-antitrypsin concentrations were measured serially in pregnant women who were normotensive and those with mild, moderate, and severe hypertension of pregnancy from 27 weeks' gestation to term. alpha 1-antitrypsin concentrations increased with advancing gestation in all four groups. In addition, the hypertensive pregnancies showed higher than normal concentrations at each stage of pregnancy, with values in the severe hypertension group being higher than values in the other two hypertensive groups. At 35-36 weeks' gestation to term the increase in alpha 1-antitrypsin in the severe hypertension group was significant (p less than 0.05) when compared with the normotensive group. Although plasma oestriol and progesterone concentrations increased with advancing gestation in all groups, there was no direct relation between their concentrations and the increase in alpha 1-antitrypsin concentration in the hypertensive groups.

Estriol↗
PubMed1984

Intracranial tuberous sclerosis in infancy.

Transfontanelle sonograms and CT scans of the brain were obtained in 2 infants with tuberous sclerosis. Each modality showed typical subependymal nodules in both infants, as well as a large mass adjacent to the foramen of Monro in one of them; in the other, peripheral cortical tubers were clearly outlined with CT but not detected by ultrasound.

Humans↗
PubMed1983

Second trimester amniotic fluid acetylcholinesterase quantitation in the prenatal diagnosis of neural tube defects.

Amniotic fluid acetylcholinesterase (AChe) activity was assayed in second trimester amniotic fluids by inhibition of non-specific cholinesterase using lysivane. Of the 196 samples analysed, 146 were from normal pregnancies; 11 (5.6%) from severe open neural tube defects; two from small open spina bifidas; seven from fetal chromosome abnormalities and two from severe skeletal dysplasias. In addition nine amniotic fluids were meconium stained and 19 (9.7%) had varying degrees of blood staining. Acetylcholinesterase values remained relatively constant from 13-21 weeks gestation in normal pregnancies and a cut-off limit of 3.2 U/l was set (mean + 2 SD). Heavily blood stained amniotic fluids were associated with AChe levels on or above the normal cut-off limit. Meconium staining caused a non-significant elevation of AChe. No significant elevation of AChe was demonstrated for fetal chromosome abnormalities, or severe skeletal dysplasias. Anencephaly and severe open spina bifida had significantly elevated AChe levels.

Acetylcholinesterase↗