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C Wesley

Publications and source records attributed to C Wesley.

8 recordsLinked to original sources
PubMed2001

Scabrous complexes with Notch to mediate boundary formation.

The mechanisms that establish and sharpen pattern across epithelia are poorly understood. In the developing nervous system, the first pattern elements appear as 'proneural clusters' In the morphogenetic furrow of the immature Drosophila retina proneural clusters emerge in a wave as a patterned array of 6-10-cell groups, which are recognizable by expression of Atonal, a basic helix-loop-helix transcription factor that is required to establish and pattern the first cell fate. The establishment and subsequent patterning of Atonal expression requires activity of the signalling transmembrane receptor Notch. Here we present in vivo and biochemical evidence that the secreted protein Scabrous associates with Notch, and can stabilize Notch protein at the surface. The result is a regulation of Notch activity that sharpens proneural cluster boundaries and ensures establishment of single pioneer neurons.

Animals↗
PubMed1992

Accumulation of P elements in minority inversions in natural populations of Drosophila melanogaster.

The accumulation of a transposable element inside chromosomal inversions is examined theoretically by a mathematical model, and empirically by counts of P elements associated with inversion polymorphisms in natural populations of Drosophila melanogaster. The model demonstrates that, if heterozygosity for an inversion effectively reduces element associated production of detrimental chromosome rearrangements, a differential accumulation of elements is expected, with increased copy number inside the minority inversion. Several-fold differential accumulations are possible with certain parameter values. We present data on P element counts for inversion polymorphisms on all five chromosome arms of 157 haploid genomes from two African populations. Our observations show significantly increased numbers of elements within the regions associated with the least common, or minority arrangements, in natural inversion polymorphisms.

Animals↗
PubMed1989

Restriction-map variation associated with the G6PD polymorphism in natural populations of Drosophila melanogaster.

Restriction-map variation was studied in 126 copies of the G6pd region in X chromosome lines of Drosophila melanogaster from North America, Europe, and Africa. Special attention was focused on the distribution of variation relative to the geographically variable polymorphism for two electrophoretic variants. Nucleotide heterozygosity as determined by eight six-cutter restriction enzymes for the 13-kb region is estimated, on the basis of the worldwide sample, to be 0.065%, which is the lowest value reported for any comparable region in the D. melanogaster genome. Significant linkage disequilibrium between electrophoretic alleles and restriction-site variation is observed for several sites. In contrast to published studies of other genetic regions, there are large insertions that reach significant frequencies and are found across considerable geographic distances. There is a clustering of this variation inside the first large intervening sequence of the G6PD gene.

Africa↗
PubMed1983

[Occlusive arteriopathy of the circle of Willis with outlined "Moya-Moya" network in a woman with migraine under oral contraception. Regressive course].

A 19-year-old woman with migraine under contraceptive therapy had transient right hemiparesis due to a minor lesion in the left hemisphere, which was probably hemorrhagic rather than ischemic. On the left side, angiography showed nearly complete obstruction of the terminal portion of the internal carotid artery, extending to the initial portion of its terminal branches, with an outlined "Moya-Moya" network. On the right side, moderate annular stenosis of the cervical portion of the internal carotid was visible. On subsequent angiographies, done 7 and 19 months later, blood flow was reestablished in the left internal carotid artery as well as in its terminal branches, but with persistent segmental stenosis. Since the stroke, the symptomatology of migrainous attacks has been altered, pointing to a left hemispheric spreading.

Adult↗
PubMed1983

[Incomplete regressive obstruction of the internal carotid artery in a female patient with fibromuscular dysplasia].

The authors report on the case of a 48-year-old woman, with no history of cardiovascular disease, presenting with a progressive right cerebral deficiency syndrome predominating in the parietal region. X-ray, arteriography and CT scan findings led to the diagnosis of right middle cerebral artery ischemic stroke, in the proximal territory, due to a practically complete occlusion of the right internal carotid artery. The patient recovered and a right carotid arteriography performed 8 months after the initial one showed repermeation of the carotid artery, as well as evidence of fibromuscular dysplasia (FMD). The authors then reviewed the literature dealing with cervico-cephalic FMD and concluded that FMD only exceptionally leads to arterial occlusion, whether by arterial dissection, intimal hyperplasia or thrombosis. This case is remarkable by its favorable outcome: the thrombus, which was unquestionably responsible for the clinical picture, dissolved spontaneously.

Arterial Occlusive Diseases↗
PubMed1980

Aortography with the long catheter needle.

The addition of side holes to the Teflon catheter used for translumbar aortography results in improved flow of contrast material and good visualization of the aorta and brachiocephalic vessels. Details of the technique and precautions for safe use are discussed.

Aortography↗
PubMed1976

[Granular cell pituicytoma (choristoma) of the pituitary stalk].

A case of granular cell tumour in the pituitary stalk is described marked by the sudden loss of visual acuity in the left eye, followed by the right years later. A comparison with 17 cases previously published and with cases of asymptomatic granular cell nodules leads the authors to suggest the term granular cell pituicytoma. They discuss the place of this neoformation among other systemic granular cell tumours (granular cell myoblastoma). Fifteen patients were operated on, complete excision being carried out in only three (including the case published). Whether complementary cobalt therapy is useful remains problematical since very few cases have been published because of the slow development of the neoplasm.

Choristoma↗