The role of Schwann cells and basal lamina tubes in the regeneration of axons through long lengths of freeze-killed nerve grafts

The ability of long acellular nerve grafts to support axonal regeneration was examined using inbred rats. Grafts (40 mm long) of tibial/plantar nerves were used either as live grafts or after freeze-drying to render the grafts acellular. The grafts were sutured to the proximal stump of severed tibial nerves in host animals which were then killed 1-12 weeks later. Axons rapidly regenerated through the living grafts but only extended 10-20 mm into the acellular grafts. This distance was achieved by 6 weeks and thereafter no significant further axonal extension occurred in the acellular grafts. A few naked axons lacking Schwann cell contact were identified in all acellular grafts, but became more numerous near the distal extent of axonal penetration into 6-12 week grafts. These axons contained large numbers of neurofilaments. When the distal 20 mm of 6 week acellular grafts (segments into which axons had not penetrated) were sutured to freshly severed tibial nerves, axons grew readily into the grafted tissue to a maximum distance of 9 mm. It is therefore likely that the limits to axonal regeneration through initially acellular grafts were set by factors intrinsic to the severed nerve. It is suggested that the limited migratory powers of Schwann cells may be one such factor. The concept that basal lamina tubes are not essential for axonal regeneration but may act as low resistance pathways for both axonal elongation and Schwann cell migration is discussed.     

Developmental Toxicity of CI-921, an Anilinoacridine Antitumor Agent

CI-921, an anilinoacridine compound active against leukemicand solid tumors, was evaluated for potential developmentaltoxicity. Intravenous injections of CI-921 in dextrose weregiven to female Sprague-Dawley rats (0.1, 0.5, and 1.0 mg/kg)on Gestation Days (GD) 6–15 and to female New ZealandWhite rabbits (0.1, 1.0 and 2.0 mg/kg) on GD 6–18. Appropriatevehicle and untreated controls were included. Maternal and fetalparameters, including external, visceral, and skeletal malformationsand variations, were assessed. Treatment of rats with 1.0 mg/kgresulted in maternal toxicity, manifested as reduced body weightgain and food consumption during and after treatment. Reducedfetal body weight, an increased incidence of stunted fetuses,malformations of the axial and appendicular skeleton, microphthalmia,and an increased number of anatomical variations (includinganomalies of the axial skeleton and apparent hydronephrosis)also occurred in rats at 1.0 mg/kg. Treatment of rabbits resultedin no apparent maternal toxicity. However, reduced fetal bodyweight, agenesis of the azygous lobe of the lung, and an increasedincidence of variations of the axial skeleton occurred at 2.0mg/kg in rabbits. These results indicate that CI-921, at thehighest dose tested in each species, produced developmentaltoxicity in the presence of maternal toxicity in rats, but inthe absence of maternal toxicity in rabbits.     

Supplying emergency hormonal contraception in the pharmacy: the perspectives of service users

□ Pharmacists have been supplying emergency hormonal contraception via patient group direction in Manchester, Salford and Trafford health action zone since late 1999 □ This paper presents preliminary results of a questionnaire survey of users experiences of obtaining emergency contraception from this source □ Four hundred and thirty out of a total of 5,020 questionnaires distributed by pharmacists were completed □ Ninety‐nine per cent of service users were either very satisfied or satisfied with the manner in which their request for emergency contraception was dealt with □ Ninety‐one per cent of respondents felt either comfortable or very comfortable discussing emergency contraception with the pharmacist     

Compliance,concordance and the revolving door of care: caring for elderly people with mental health problems

□ The project involved community pharmacists receiving specialised training, becoming integrated into the community mental health teams and providing pharmaceutical care when making joint domiciliary visits with the key workers. □ Community pharmacists, psychiatrists and key workers all wanted the project to develop into a service and had similar views about the general benefits of the study. However, they had contrasting expectations of the project, based on their own perspectives on compliance, concordance and models of care □ The key workers valued the provision of monitored dosage systems for patients with confusion or memory problems. But the pharmacists felt that they were being expected to organise compliance aids; they recognised that it was their role to assess complaince and that other measures could be taken before organising an MDS □ The psychiatrists stated that involuntary non‐compliance with medication, arising from confusion, memory and physical problems, was a major issue and the project had made improvements in this area; they wanted to keep patients in the community and particularly valued reductions in morbidity, relapses and the “revolving door of care”