Biomedical subjects

A Bayliss

Publications and source records attributed to A Bayliss.

4 recordsLinked to original sources

PubMed1992

Lead uptake in motor axons.

In an attempt to determine whether lead (Pb) in striated muscle can be taken up by motor axon, mice were injected intramuscularly with a 5% Pb nitrate solution, and the passage of Pb through the tissues was traced with electron microscopy. Thirty minutes after injection in the tibialis anterior muscle, Pb was seen at the sarcolemma and axolemma of the neuromuscular junction (NMJ) and in the adjacent sarcoplasmic reticulum (SR). Pb was also present in the axoplasm and mitochondria of terminal and preterminal motor axons. The presence of Pb was confirmed with x-ray elemental microanalysis. The results indicate that there is a pathway for intramuscular Pb to enter terminal motor axons. This supports the hypothesis that some forms of motor neuron disease (MND) may be due to axonal uptake and retrograde transport of Pb.

Animals↗

PubMed1992

The effect of nerve crush and botulinum toxin on lead uptake in motor axons.

After lead (Pb) is injected into striated muscle it binds to the sarcolemma of the neuromuscular junction (NMJ) and crosses into the terminal axons of motor neurons. To find out whether this intra-axonal accumulation of Pb is due to active transport or to diffusion down a concentration gradient, Pb uptake into motor axons of mice was studied at active and inactive NMJs. Twenty-four hours after sciatic nerve crush, 0.1 ml of 5% lead nitrate was injected into the tibialis anterior muscle and 30 min later the location of Pb was sought with electron microscopy and X-ray elemental analysis. A greatly reduced amount of Pb entered the axons after nerve crush compared to non-nerve crush animals, indicating that an active NMJ is required for intra-axonal Pb accumulation. To test if Pb could be entering the axon via recycling vesicles, botulinum toxin (BoTx) was injected into the muscle 24 h before Pb injection. There was no difference in intra-axonal Pb uptake in control and BoTx-injected animals, indicating that Pb is unlikely to use recycled vesicles to enter the axon.

Animals↗

PubMed1988

Hysterosalpingographic diagnosis of a single cervical ectopic ureter.

Single ectopic ureters terminating in the female genital tract are rare congenital anomalies caused by an abnormally lateral origin of the ureteric bud from the mesonephric duct in the three- to four-week embryo. The ureter remains intimately involved with mesonephric duct remnants, which acquire a communication with müllerian structures. Hysterosalpingography in a continent infertile patient outlined a single cervical ureter from a hypoplastic kidney draining into Gartner's duct remnants. No previous case of single cervical ectopic ureter has been reported without a müllerian anomaly, nor has a single cervical ureter been demonstrated on hysterosalpingography.

Adult↗

PubMed1980

Consent for mastectomy.

The value of a system for reducing the number of women with breast lumps who consent unnecessarily to mastectomy was assessed. Sixty-one patients with breast lumps were divided preoperatively into three groups with benign, doubtful, and malignant lumps according to clinical, mammographic and ultrasound criteria. On the basis of these criteria written consent was requested from 29 patients for mastectomy and from 32 for only excision of the lump. Fourteen of the 29 patients who gave consent for mastectomy had carcinomas, and none of the 32 patients consenting to only lump excision. In an attempt to improve further on these results the same 61 patients were analysed retrospectively. Criteria based on age and the results of clinical examination and mammography were devised. By using these criteria only 19 women would have had to give consent for mastectomy. This new policy, which was devised to spare many women the stress of consenting unnecessarily to mastectomy, requires to be tested further in a much larger series of patients.

Adolescent↗