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G Turner

Publications and source records attributed to G Turner.

At least 217 records · Page 12Linked to original sources
PubMed1988

X-linked recessive inheritance of an orofaciodigital syndrome with partial expression in females and survival of affected males.

We describe a family with clinical features of orofaciodigital (OFD) syndrome type 2 or Mohr syndrome, X-linked recessive inheritance and survival of affected males which has not previously been reported. Four affected males in three generations have survived into infancy and two female heterozygotes have very mild expression. Foetal ultrasonography enabled antenatal diagnosis.

Abnormalities, Multiple↗
PubMed1987

Sequence and centromere proximal location of a transformation enhancing fragment ans1 from Aspergillus nidulans.

The Aspergillus nidulans sequence ans1, previously known to enhance transformation frequencies of pyr4-based vectors, was shown to enhance the efficiency of argB and trpC-based vectors. Increased efficiencies could be obtained by constructing vectors containing argB and ans1 or by cotransforming selectable plasmids (containing argB, trpC, or pyr4) with the non-selectable ans1 sequence. The preponderance of evidence suggests that the mechanism of ans1 activity does not involve homologous recombination events, in spite of the presence of multiple regions of homology in the A. nidulans genome. Genetic mapping localized ans1 to the vicinity of the centromere of linkage group I. The nucleotide sequence of a 1.8 Kb functional subclone of ans1 was determined and found to be highly A + T rich (81%).

Aspergillus nidulans↗
PubMed1987

FDA's conduct, review, and evaluation of inspections of clinical investigators.

This review of the Food and Drug Administration's Bioresearch Monitoring Program focuses on the inspection of clinical investigators who study investigational drugs. The differences between routine, "for-cause," and bioequivalency/bioavailability inspections are examined, with emphasis on the responsibilities of the clinical investigator, reasons for conducting the inspections, and problems found. Important aspects of the inspection report, such as protocol adherence, records maintenance, informed consent, institutional review board approval, and drug accountability, are outlined. The disqualification and consent agreement processes for investigators with serious problems are explained. FDA policies on third-party notification and remote data entry are noted.

Drug Evaluation↗
PubMed1987

The influence of socioeconomic factors on the occurrence of fetal alcohol syndrome.

This study was designed to compare manifestations of FAS in the offspring of lower and upper middle class chronic alcoholic mothers, and to compare these offspring with those of nonalcoholic controls. There was highly significant difference in the incidence of FAS offspring between upper middle and lower class alcoholic mothers, 4.5% versus 70.9% respectively. Mean weight, length, and head circumference at birth in children of upper middle class alcoholic women was -ISD, those of lower class alcoholic women fell into -2SD. All other parameters, congenital malformation rate, failure to thrive, mental retardation were also significantly greater in children of lower class alcoholic women (p less than or equal to .01). Attention deficit disorder was found in 21% of upper middle class offspring of alcoholic women as compared to 71% in the children of the lower socioeconomic group (p less than or equal to .01).

Attention Deficit Disorder with Hyperactivity↗
PubMed1986

Preventive screening for the fragile X syndrome.

In an Australian population of 1.2 million, we screened 1977 intellectually handicapped persons, who were identified through the public schools and sheltered workshops, for the X-linked semidominant fragile X syndrome. We excluded 527 because they had another known diagnosis. The remaining 1450 were offered chromosomal analysis. Of the 1117 who consented (77 percent), an additional 196 were excluded, and among the 921 who were tested cytogenetically, 40 probands were found. Prevalence rates for persons with an intellectual handicap and the fragile X syndrome in the public school population were 1:2610 for males and 1:4221 for females. Family studies identified 84 women who were either obligate carriers or at high risk of being carriers, who were under the age of 35 and had no children. These women were given genetic counseling, and the availability of antenatal diagnosis was explained to them. If each of these 84 women had two children, 27 of their sons would have an intellectual handicap. We recommend cytogenetic screening for the fragile X syndrome in all currently identified intellectually handicapped people, followed by routine screening of children newly identified as intellectually handicapped in the school system.

Australia↗
PubMed1986

Transformation of Aspergillus nidulans with a cloned, oligomycin-resistant ATP synthase subunit 9 gene.

An allele (oliC31) of the A. nidulans oliC gene has been cloned using homology with the equivalent gene from N. crassa. OliC31 codes for an oligomycin-resistant, triethyltin-hypersensitive form of subunit 9 of the mitochondrial ATP synthase complex. Direct selection for oligomycin-resistance was possible following transformation of A. nidulans with the oliC31 gene. The phenotypes of transformants cultured in the presence of oligomycin were indicative of the position of integration of the transforming plasmid within the genome. Subsequent recombination events involving the integrated oliC31 gene were also apparent from altered levels of resistance to oligomycin or triethyltin. This gene should prove useful as a marker for transformation of strains lacking auxotrophic lesions and in gene replacement or disruption experiments.

ATP Synthetase Complexes↗
PubMed1986

Gene cloning in Aspergillus nidulans: isolation of the isocitrate lyase gene (acuD).

An Aspergillus nidulans gene library was constructed in a high-frequency transformation vector, pDJB3, based on the Neurospora crassa pyr4 gene. This gene library was used to isolate the structural gene for isocitrate lyase (acuD) by complementation of a deficiency mutation following transformation of A. nidulans. Plasmids rescued in Escherichia coli were able to transform five different A. nidulans acuD mutants. Transformation using plasmids containing the cloned fragment resulted in integration at the acuD locus in six of nine transformants.

Aspergillus nidulans↗
PubMed1986

The ATP synthase subunit 9 gene of Aspergillus nidulans: sequence and transcription.

We have determined the nucleotide sequence of the Aspergillus nidulans nuclear gene oliC31, which encodes subunit 9 of mitochondrial ATP synthase. The open reading frame contains no introns and specifies a predicted protein of 143 amino acids comprising a pre-sequence of 62 residues and a mature protein of 81 residues. The amino acid homology with the equivalent Neurospora crassa protein is 50% for the pre-sequence and 80% for the mature protein. A comparison with this and other imported mitochondrial proteins has revealed conserved regions which may be important for transport or subsequent processing. Multiple transcription initiation and polyadenylation sites have been identified. The promoter region of the oliC31 gene is characterised by long pyrimidine-rich tracts preceding the transcription initiation sites.

Amino Acid Sequence↗
PubMed1985

Further segregation analysis of the fragile X syndrome with special reference to transmitting males.

A new series of 96 pedigrees with the fra(X) syndrome was analysed using complex segregation analysis with pointers, defining affection as any degree of mental impairment. These families were found to exhibit the same segregation pattern as the first series of 110 pedigrees (Sherman et al. 1984). The best estimate for penetrance of mental impairment in males was 79% and in females was 35% for the combined data. Again, there was little evidence for sporadic cases among affected males. Many more intellectually normal transmitting males have been observed since the existence of such males and the concomitant need to investigate the paternal side of pedigrees was recognized. On further investigation of all 206 pedigrees from the old and new data sets, the sibships of nonexpressing males appeared to be different from those of expressing males. Our analysis, using mental impairment as the phenotype, suggested that obligate carrier mothers and daughters of intellectually normal transmitting males are rarely, if ever, mentally impaired and that the sibs of transmitting males are much less likely to be retarded than the sibs of mentally impaired males. Though mothers and daughters of transmitting males are similar in phenotype, the expression of the gene in their offspring appears to be different: the penetrance of mental impairment is higher in offspring of intellectually normal daughters of transmitting males than in offspring of intellectually normal mothers of transmitting males. The implications of these observations for genetic counseling and for genetic models of the fra(X) syndrome are discussed.

Female↗
PubMed1985

Development of a high-frequency transforming vector for Aspergillus nidulans.

The pyr4 gene of Neurospora crassa, which codes for orotidine-5'-phosphate decarboxylase, is capable of transforming an Aspergillus nidulans pyrG mutant by chromosomal integration, despite low homology between the transforming DNA and the recipient genome. Integration of pFB6, a plasmid carrying pyr4 and capable of replication in Escherichia coli, was not observed at the pyrG locus. The efficiency of transformation was considerably enhanced (50-100 fold) by inclusion in the transforming vector of a 3.5-kb A.nidulans chromosomal sequence, ans1. Although this sequence was isolated on the basis of replicating activity in Saccharomyces cerevisiae, there was no evidence for such activity in A.nidulans. Part of the ans1 fragment appears to be reiterated in the A.nidulans genome, though it is not yet clear whether this is directly responsible for the high transformation frequency. The efficiency of transformation of A.nidulans by plasmids bearing ans1, using an improved protocol, was approx. 5 X 10(3) stable transformants per microgram of plasmid DNA.

Aspergillus nidulans↗
PubMed1985

Glycosylation of maternal hair and cord skin during pregnancy in diabetic and non-diabetic women.

A study of 15 insulin-dependent diabetics (IDD), 4 gestational diabetics (GDM), and 21 non-diabetic women was undertaken to assess non-enzymatic glycosylation in maternal hair, cord skin, and cord blood. Glycosylation of maternal hair was stable from tip to root in controls. In the IDD group, levels were highest at the tip, but were significantly lower in the middle and scalp segment (p less than 0.01), both tip and middle segments were higher than control values (p less than 0.01). In contrast, only the scalp segment of hair from the GDM group had a higher than normal level of glycosylation (p less than 0.01). Cord skin and cord blood glycosylation were significantly increased in the IDD group compared with normal (0.100 +/- 0.002 vs 0.074 +/- 0.008 mumol fructosamine/100 mg, p less than 0.01, and 0.160 +/- 0.002 vs 0.14 +/- 0.008, p less than 0.05, mean +/- S.E.M.), respectively. Only cord skin glycosylation was increased in the GDM group (0.116 +/- 0.003, p less than 0.01). Thus near normal glycaemic control of maternal insulin-dependent diabetes during pregnancy was associated with small but significant increases in cord skin glycosylation and a fall towards normal in maternal hair glycosylation which may provide a useful retrospective index of diabetic control.

Adult↗
PubMed1985

EEG and evoked potential changes during gas- and liquid-breathing dives to 1000 msw.

To test the hypothesis that compression in helium gas and compression without gas (hydrostatic compression) both produce the same neurological symptoms of high pressure nervous syndrome (HPNS), groups of 4 to 5 dogs were exposed to one of the following: (a) a 2-h surface control breathing He-O2 gas; (b) compression to 700-1000 msw breathing He-O2 gas; (c) a 2-h liquid-breathing control [ventilation with warmed (38 degrees C), oxygenated fluorocarbon liquid, FC-80]; and (d) "near hydrostatic" compression to 700-1000 msw while being ventilated with liquid from a sealed reservoir. Power spectra obtained from scalp-recorded EEG signals revealed a significant compression-related shift of power from the normally dominant 5-8 Hz band to the 8-11 Hz band. This effect was greatest at 600 msw and occurred equally in both dive groups. At very high pressures (greater than 900 msw) power in this 6-10 Hz range became reduced whereas 16-22 Hz activity increased as the EEG flattened. Somatosensory evoked potentials (SEPs) were elicited by subdermal electrical stimulation in the foreleg (n = 120). The latency of P1 (approximately 31 ms) did not change in any group; transmission time to cortex was unaltered by time or pressure. However, the "late-wave" P4 (approximately 250 ms) was slowed by 32-35 ms at 1000 msw in both groups (P less than 0.003 in He-O2). Since these main symptoms were provoked equally in both He-O2 and FC-80 dive groups, helium pressure did not play a significant role in the etiology of HPNS in this animal model. It is concluded that the HPNS is primarily a result of excessive pressure per se or rate of change of pressure per se.

Animals↗
PubMed1984

The marker (X) syndrome: a cytogenetic and genetic analysis.

The results of a cytogenetic and segregation analysis of 110 pedigrees of the mar (X) syndrome are reported. The cytogenetic study indicated an inverse relationship between IQ and the mar(X) frequency in females but not in males. A small but significant effect of age on mar(X) frequency was observed in both males and females, but in females it was restricted to those of normal intelligence, retarded females showing no significant effect. Classical segregation analysis was performed using the program SEGRAN, analysing sexes separately. A 20% deficit of affected males was observed, the most plausible explanation for the majority of these cases being incomplete penetrance. Since this was an unexpected result, the data were scrutinized for possible biases; however, correction of these had little effect on the estimate. The penetrance of mental impairment in carrier females was estimated to be 30% and of mental impairment and/or mar(X) expression to be 56%. Thus 44% of carriers cannot be detected with our definition of affection. No evidence for sporadic cases among affected males was found. Complex segregation analysis was performed using the sex-linked version of POINTER, analysing sexes together. This was done in order to test the results from classical segregation analysis, to test for family resemblance and to estimate mutation rates. It was confirmed that there was a 20% deficit of affected males, that penetrance of mental impairment in females was approximately 30% and that there was no evidence for sporadic males. Thus all males with the gene appear to have received it from their carrier mothers and all mutations must occur in sperm. The mutation rate in sperm was estimated to be as high as 7.2 X 10(-4), implying that over one-half of random carrier females are fresh mutants. Our results have important implications for genetic counseling as they imply that all mothers of isolated affected males are carriers, that normal brothers of affected males have a 17% chance of carrying the gene and transmitting it to all their daughters, and that normal sisters of affected males have, at most, a 30% chance of being carriers. Since there are biases in the data due to the testing of particular individuals, these probabilities must be considered approximations until they are independently confirmed.

Adolescent↗
PubMed1983

Transformation of Aspergillus nidulans by the orotidine-5'-phosphate decarboxylase gene of Neurospora crassa.

Relief of an auxotrophic requirement for uridine in Aspergillus nidulans strain G191 has been achieved by transformation with a segment of Neurospora crassa DNA containing the corresponding gene coding for orotidine-5'-phosphate decarboxylase. The mitotic stability of such transformants suggests that the DNA has integrated into the genome. Southern hybridisation analysis of DNA isolated from transformants revealed the presence of pBR322 sequences which have integrated into the host genome along with the N. crassa DNA.

Aspergillus nidulans↗