Tonotopic Ca2+ dynamics and sound processing in auditory interneurons of the bush-cricket Mecopoda elongata.

Two auditory neurons, TN-1 and ON-1, in the bush-cricket, Mecopoda elongata, have large dendritic arborisations which receive excitatory synaptic inputs from tonotopically organised axonal terminals of auditory afferents in the prothoracic ganglion. By combining intracellular microelectrode recording with calcium imaging we demonstrate that the dendrites of both neurons show a clear Ca2+ signal in response to broad-frequency species-specific chirps. Due to the organisation of the afferents frequency specific auditory activation should lead to local Ca2+ increases in their dendrites. In response to 20 ms sound pulses the dendrites of both neurons showed tonotopically organised Ca2+ increases. In ON-1 we found no evidence for a tonotopic organisation of the Ca2+ signal related to axonal spike activity or for a Ca2+ response related to contralateral inhibition. The tonotopic organisation of the afferents may facilitate frequency-specific adaptation in these auditory neurons through localised Ca2+ increases in their dendrites. By combining 10 and 40 kHz test pulses and adaptation series, we provide evidence for frequency-specific adaptation in TN-1 and ON-1. By reversible deactivating of the auditory afferents and removing contralateral inhibition, we show that in ON-1 spike activity and Ca2+ responses increased but frequency-specific adaptation was not evident.

Multiple deprivation and geographic distance to community physical activity events - achieving equitable access to parkrun in England.

OBJECTIVES: To evaluate geographic access to free weekly outdoor physical activity events ('parkrun') in England, with a particular focus on deprived communities, and to identify optimal locations for future events to further maximise access. STUDY DESIGN: This study is a cross-sectional ecological analysis of the socio-economic disparities in geographic access to parkrun events in England in late 2018. METHODS: We combined geolocation data on all English Lower Layer Super Output Areas and parkrun events to calculate geodesic distances to the nearest event for more than 32,000 communities in England. We use this measure of geographic access to summarise the relationship between access and socio-economic deprivation, measured using the index of multiple deprivation. We then used geographic coordinates of public green spaces in England to conduct a simple location-allocation analysis to identify 200 locations for future event locations that would maximise access. RESULTS: In England, 69% of the population live within 5 km of one of the 465 parkrun events. There is a small negative correlation between distance and deprivation, indicating that access is slightly better in more socio-economically deprived areas. Setting up an additional 200 events in optimal locations would improve access: the average distance to the nearest parkrun event would improve by 1.22 km, from 4.65 km to 3.43 km, and approximately 82% of the English population would live within 5 km of a parkrun event. CONCLUSION: Over two-thirds of the English population live within 5 km of a parkrun event, and contrary to our expectation, we find that geographic access is slightly better for those living in more deprived communities. Creating additional events may improve geographic access, but effective strategies will still be needed to increase engagement in new and existing events by those living in socio-economically deprived areas.

A buckling region in locust hindlegs contains resilin and absorbs energy when jumping or kicking goes wrong.

If a hindleg of a locust slips during jumping, or misses its target during kicking, energy generated by the two extensor tibiae muscles is no longer expended in raising the body or striking a target. How, then, is the energy in a jump (4100-4800 µJ) or kick (1700 µJ) dissipated? A specialised buckling region found in the proximal hind-tibia where the bending moment is high, but not present in the other legs, buckled and allowed the distal part of the tibia to extend. In jumps when a hindleg slipped, it bent by a mean of 23±14 deg at a velocity of 13.4±9.5 deg ms(-1); in kicks that failed to contact a target it bent by 32±16 deg at a velocity of 32.9±9.5 deg ms(-1). It also buckled 8.5±4.0 deg at a rate of 0.063±0.005 deg ms(-1) when the tibia was prevented from flexing fully about the femur in preparation for both these movements. By experimentally buckling this region through 40 deg at velocities of 0.001-0.65 deg ms(-1), we showed that one hindleg could store about 870 µJ on bending, of which 210 µJ was dissipated back to the leg on release. A band of blue fluorescence was revealed at the buckling region under UV illumination that had the two key signatures of the elastic protein resilin. A group of campaniform sensilla 300 µm proximal to the buckling region responded to imposed buckling movements. The features of the buckling region show that it can act as a shock absorber as proposed previously when jumping and kicking movements go wrong.

Relationships between attachment, appraisal, coping and adjustment in men and women experiencing infertility concerns.

BACKGROUND: Attachment style may influence distress and relationship satisfaction in infertile couples. Appraisal and coping have also been linked to adjustment to infertility and may be related to attachment patterns. The study examined these associations in men and women around the time of attending initial appointments at fertility clinics. METHODS: Attachment, appraisal, coping, general well-being, infertility-related stress and relationship satisfaction questionnaires were completed by 98 women and 64 men. Data were analysed by gender comparisons, correlations and path analysis. RESULTS: Attachment anxiety was associated with well-being in women via appraisal of infertility as a loss and use of self-blame and avoidance (SBA) coping. Attachment anxiety was also linked with infertility-related stress through SBA. In men, attachment anxiety was associated with well-being and infertility-related stress again via SBA coping. Attachment anxiety and avoidance were related to lower relationship satisfaction in women, whereas only the former was important for men. CONCLUSIONS: Attachment patterns link to couples' relationship satisfaction and are associated with adjustment via appraisal and coping. Identification of such patterns may assist in identifying need and tailoring cognitive interventions to individuals. Participants were mainly white and well-educated, and wider generalization cannot automatically be assumed.

Influence of formula versus breast milk on cholesterol synthesis rates in four-month-old infants.

We investigated whether supplementation of regular formula (RF) with cholesterol (Ch) (RF+Ch) influenced circulating Ch levels and de novo synthesis compared with their breast-fed (BF) counterparts in 4-mo-old infants. The incorporation rate of deuterium in body water into erythrocyte membrane-free Ch over 48 h was used as an index of cholesterogenesis. Plasma total-Ch and LDL-Ch concentrations were highest (p < 0.02) in BF infants, compared with infants in the RF-fed groups. Infants in the RF+Ch groups showed an intermediate response; their plasma total-Ch and LDL-Ch concentrations were not significantly different from the BF or the RF-fed groups. Plasma total/HDL-Ch and LDL/HDL-Ch ratios were higher (p < 0.05) in BF, and higher in RF+Ch-fed infants, compared with those fed RF, whereas not different between BF and RF+Ch-fed infants. At 4 mo of age, Ch FSR was 4-fold lower (p < 0.0001) in BF versus other groups, but not significantly different between RF- and RF+Ch-fed infants. Thus, despite addition of Ch to the concentration found in breast milk, FSR remained elevated compared with that of the group fed breast milk, with an intermediate response in circulating Ch levels. It is speculated that factors other than Ch intake account for the differential Ch metabolism between formula-fed and BF infants.

Possible limited bone loss with suppressive thyroxine therapy is unlikely to have clinical relevance.

To determine the effect of suppressive doses of thyroxine (T4) on bone mass, we studied 50 women on suppressive doses of T4 for 3-27 years (mean of 11 years). Twenty-five had nontoxic goiter and 25 had well-differentiated thyroid carcinoma. Fifty controls were matched for age, menopausal status, and body mass index. Bone mineral density (BMD) was measured in the lumbar spine (LS), femoral neck (FN), trunk (TK), and extremities (EXT) by dual-energy X-ray absorptiometry (DXA). In addition, the trunk area was measured by neutron activation analysis and recorded as a calcium bone index (CaBI). Twenty-one patients were restudied with DXA measurements at a mean of 1.5 +/- 0.5 (1 SD) years. The total population of 50 patients showed no difference in bone mass from controls. In patients with nontoxic goiter, there was no evidence of any loss in bone mass. Cancer patients showed insignificant reductions of 2-5% in BMD of LS, FN, and TK and a significant 5% reduction in BMD of EXT, compared to controls, and a 12% reduction in CaBI compared to goiter patients. Cancer patients had a slightly higher (p < 0.001) mean daily dose of T4 than goiter patients (0.23 vs 0.15 mg/day) but had a similar degree of TSH suppression. BMD and CaBI values did not correlate with free T4 index) with the daily T4 dose, accumulative dose, or with duration of T4 therapy. There were no significant changes in bone mass in either goiter or cancer patients restudied after a mean of 1.5 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Specialist training.

Specialist training must be reshaped to meet the challenges of new systems for the delivery of health care and rapid expansion in biomedical knowledge. An adequate and affordable supply of trained specialists and generalists able to deal with the health problems of populations served, is the responsibility of governments and policy-makers that fund and those who deliver graduate education. Clearly defined objectives for specialist training are needed, linked to planning for the medical workforce size. A balance between numbers of specialists and generalists is essential, although flexibility in programmes should allow individuals to change. Curricula for all specialties should be published. Strategies and methods for delivery of graduate education and training must be coherent with those of medical schools. Training should be planned and sequenced to meet the identified needs of individuals. Those who teach should themselves learn how to train and assess trainees. The location for training should reflect present and future clinical practice if disfunction between medical education and the health of populations served and their need is to be avoided. Specialist training should form the basis for continuing education by encouraging lifelong, evidence-based learning. Any reshaping of specialist training must be consistent with the continuum of medical education. Instruments for assessment of specialists in training have to be refined, based on action research. Ensuring mastery in the competencies of each component of the curriculum is essential. Those competencies will change in consequence of altered societal needs plus advances in technology and biomedical knowledge.

The hospital component of vocational training for general practice.

Trainees and educationalists in general practice have some grounds for suggesting that the hospital component of vocational training should be restructured and teaching improved. However, the implications for other trainees and secondary care have to be considered. Changes that are needed include a curriculum for senior house officers in each specialty; appointment of training consultants with the necessary skills; and a different attitude by everyone towards study leave, including arrangements for funding. The optimum duration of hospital posts for trainees in general practice might be shorter than now, but the effects on others must be considered and competencies guaranteed in a briefer training period. Changes in the regulations for vocational training could help to improve specialist experience if trainees in general practice were allowed to be supernumerary. Alternatively, senior house officer posts for trainees in general practice could be split between secondary and primary care, thus encouraging a broader perspective.

Educational audit of postgraduate medical education.

This project examined the academic audit of postgraduate medical education, and went on to research, design and implement an educational audit system for use in Mersey Region, UK. Issues found to be significant included ownership of both standards and results, norming, and the levels of aggregation of data. The project has demonstrated that designing and implementing a system of feedback which is effective and sustainable is feasible, but requires the agreement and support of tutors as to its objectives and use. The resulting system has now been tested across a range of courses and programmes of meetings in Mersey Region, and has been accepted by the Postgraduate Office as the basis for future development.

Sudden rupture of an indirect inguinal hernial sac with extravasation in two patients on continuous ambulatory peritoneal dialysis.

Continuous ambulatory peritoneal dialysis (CAPD) is commonly used to treat patients suffering from end-stage renal failure. This method can be used on a long-term basis and in the short term for patients awaiting renal transplantation. Inguinal hernias are a potential source of morbidity for these patients. Therefore, when patients with inguinal hernias require long-term peritoneal dialysis, the hernia should be repaired if the patient's medical status will allow it. The authors report on two patients maintained on CAPD who experienced rapid enlargement and perforation of a previously undiagnosed asymptomatic inguinal hernia. The hernia was repaired successfully, without complication, in both cases.

Libraries, postgraduate medical education and the management of change.

The changes surrounding the funding of postgraduate medical and dental education are outlined and the funding implications for libraries considered. The management of this period of change is vital if all players are to appreciate the advantages of implementation, not least cost-effectiveness. In conclusion three problem areas in the post-reform NHS are identified and briefly discussed: the need for access and provision of information to all; development of regional librarian role across all regions to ensure effective co-ordination of resources; a national policy which will integrate national, regional and unit structures for the delivery of health-care information needs to be developed.

Relevance of vitamin D metabolite concentrations in supporting the diagnosis of primary hyperparathyroidism.

We compared the relationships between 25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D [1,25(OH)2D] levels in patients with primary hyperparathyroidism (PHPT) and 38 volunteer blood donors. There was no significant difference in mean 25(OH)D levels between patients with PHPT (34 +/- 21 nmol/L; n = 21) and the donor samples (41 +/- 19 nmol/L; n = 38). Serum 1,25(OH)2D levels were higher in the patients with PHPT compared with the donors (122 +/- 61 pmol/L vs 56 +/- 41 pmol/L; p less than 0.001). The 95th percentile 1,25(OH)2D value for the donors was exceeded in 65% of the patients with PHPT. There was a significant correlation between serum 1,25(OH)2D versus 25(OH)D in the patients with PHPT (r = 0.50; p less than 0.05) but not in the donors (r = 0.02). We conclude from the distinct elevation in 1,25(OH)2D levels in the majority of our patients with PHPT that the concentration of this parathyroid hormone-dependent hormone can be of critical value in corroborating the diagnosis of PHPT.

Bone mineral mass associated with postmenopausal vertebral deformities.

Vertebral morphometry on thoracic and lumbar spine radiographs and bone mass measurements were carried out on 215 patients investigated for postmenopausal osteoporosis. Bone mineral mass was measured on the central third of the skeleton by neutron activation analysis and the result, normalized for body size, expressed as a calcium bone index (CaBI). The normal CaBI value for females (20-40 years) is 0.97 (0.11) with a lower limit for these young, normal women, of 0.75. Vertebral compression deformity was defined as a mean height more than 15% lower than adjacent normal vertebrae. Thoracic and lumbar anterior wedge deformities and central compression were defined as anterior/posterior (A/P) or mid/posterior (M/P) height ratios of less than 0.75. For the 129 patients without vertebral deformities, the mean CaBI was 0.80 (0.12) (1 SD) and 32% of these patients had CaBI values below the normal young adult range (CaBI less than 0.75). In 20 patients, vertebral deformities were limited to 1 or 2 mid-thoracic vertebrae, and the mean CaBI values for these 20 patients was 0.81 (0.15), equal to that for patients without any vertebral deformity. For the remaining 67 patients, (i.e., patients with one or more vertebral deformities involving at least one distal thoracic or one lumbar vertebra) the mean CaBI value was 0.66 (0.10), 17% below the value for patients without vertebral deformities. Low CaBI values (CaBI less than 0.75) were observed in 87% of these patients, consistent with the diagnosis of osteoporotic fractures. Based on our CaBI results, however, mid-thoracic deformity was not associated with significant osteopenia and is not, therefore, diagnostic of osteoporotic fracture.

The long-term treatment of steroid osteoporosis with fluoride.

Twenty-two patients with steroid-induced osteoporosis were studied retrospectively to assess the effects on bone mass of fluoride therapy over 4 years. Thirteen of 19 patients with miscellaneous disorders and 2 with Cushing's syndrome received 1 g calcium/day, 50,000 IU vitamin D (D) weekly, and 40-60 mg/day sodium fluoride (F). Six patients with miscellaneous disorders and one with Cushing's syndrome received only Ca and vitamin D. The mean (+/- SD) cumulative dose of prednisone for fluoride-treated patients at the beginning of the study was 42 +/- 25 g, and for those patients treated with only Ca and vitamin D, 45 +/- 47 g, and during the study the cumulative dose was comparable in both groups. The bone mineral mass of the central skeleton was measured by neutron activation analysis and the results expressed as the calcium bone index (CaBI) which normalizes the results to that of young adults of the same body size (normal range 0.75-1.2). In the 13 patients with miscellaneous disorders treated with fluoride, the mean +/- SD CaBI rose from 0.65 +/- .03 to 0.75 +/- .03 after 3 years p less than 0.001) and to 0.81 +/- .11 at 4 years. Patients without fluoride had an initial mean CaBI of 0.70 +/- .08 and it was not significantly changed over 3 years, 0.68 +/- .09 and 4 years, 0.71 +/- .09. The rise in CaBI in fluoride-treated patients with steroid-induced osteoporosis including Cushing's syndrome was comparable to that of 61 patients with postmenopausal osteoporosis treated with fluoride.(ABSTRACT TRUNCATED AT 250 WORDS)