Challenges and solutions to returning to clinical training after research: a multidisciplinary survey of integrated academic trainees in West Yorkshire, United Kingdom

BACKGROUND

Time out of clinical training can impact medical trainees' skills, competence and confidence. Periods of Out of Programme for Research (OOPR) are often much longer than other approved mechanisms for time of out training. The aim of this survey study was to explore the challenges of returning to clinical training following OOPR, and determine potential solutions.

METHODS

All current integrated academic training (IAT) doctors at the University of Leeds (United Kingdom) and previous IAT trainees undertaking OOPR in the local region (West Yorkshire, United Kingdom)(n = 53) were invited to complete a multidisciplinary survey.

RESULTS

The survey was completed by 33 participants (62% response rate). The most relevant challenges identified were completing the thesis whilst transitioning back to clinical work, the rapid transition between full-time research and clinical practice, a diminished confidence in clinical abilities and isolation from colleagues. Potential solutions included dedicated funds allocated for the renewal of lapsed skills, adequate notice of the clinical rotation to which trainees return, informing clinical supervisors about the OOPR trainee returning to practice and a mandatory return to standard clinical days.

CONCLUSIONS

Addressing these issues has the potential to improve the trainee experience and encourage future trainees to take time out of training for research activities.

Measuring colposcopy quality in Canada: development of population-based indicators

Background

Colposcopy is a key part of cervical cancer control. As cervical cancer screening and prevention strategies evolve, monitoring colposcopy performance will become even more critical. In the present paper, we describe population-based colposcopy quality indicators that are recommended for ongoing measurement by cervical cancer screening programs in Canada.

Methods

The Pan-Canadian Cervical Cancer Screening Network established a multidisciplinary expert working group to identify population-based colposcopy quality indicators. A systematic literature review was conducted to ascertain existing population and program-level colposcopy quality indicators. A systems-level cervical cancer screening pathway describing each step from an abnormal screening test, to colposcopy, and back to screening was developed. Indicators from the literature were assigned a place on the pathway to ensure that all steps were measured. A prioritization matrix scoring system was used to score each indicator based on predetermined criteria. Proposed colposcopy quality indicators were shared with provincial and territorial screening programs and subsequently revised.

Results

The 10 population-based colposcopy quality indicators identified as priorities were colposcopy uptake, histologic investigation (biopsy) rate, colposcopy referral rate, failure to attend colposcopy, treatment frequency in women 18-24 years of age, re-treatment proportion, colposcopy exit-test proportion, histologic investigation (biopsy) frequency after low-grade Pap test results, length of colposcopy episode of care, and operating room treatment rate. Two descriptive indicators were also identified: colposcopist volume and number of colposcopists per capita.

Summary

High-quality colposcopy services are an essential component of provincial cervical cancer screening programs. The proposed quality and descriptive indicators will permit colposcopy outcomes to be compared between provinces and across Canada so as to identify opportunities for improving colposcopy services.

Prepregnancy maternal body mass index and venous thromboembolism: a population-based cohort study

OBJECTIVE

To assess the relation between maternal body mass index (BMI) and pregnancy-related venous thromboembolism (VTE).

DESIGN

Cohort study.

SETTING AND POPULATION

A total of 2 449 133 women with singleton pregnancies who underwent delivery hospitalisation in California between 2008 and 2012.

METHODS

Association of pre-pregnancy BMI and the risk of an antepartum and postpartum VTE was examined using logistic regression, with normal BMI as reference.

MAIN OUTCOME MEASURES

Antepartum and postpartum VTE-related hospitalisation.

RESULTS

The prevalence of antepartum and postpartum VTE increased with increasing BMI (antepartum: 2.3, 3.0, 3.8, 4.2, 4.7, and 10.6 per 10 000 women for underweight, normal BMI, overweight, obesity class I, II, and III, respectively, P < 0.001; postpartum: 2.0, 3.1, 3.9, 5.6, 9.0, and 13.2 per 10 000 women, P < 0.01). The adjusted odds of antepartum and postpartum VTE increased progressively with increasing BMI, with obesity class III women having the highest risk of pregnancy-related VTE compared with normal BMI women: adjusted odds ratio for antepartum VTE: 2.9; 95% CI 2.2-3.8 and adjusted odds ratio for postpartum VTE: 3.6; 95% CI 2.9-4.6.

CONCLUSIONS

Our findings clearly demonstrate an increasing risk of pregnancy-related VTE with increasing BMI.

TWEETABLE ABSTRACT

Obesity was associated with increased odds of antepartum and postpartum venous thromboembolism.

Prevalence of active Charcot disease in the East Midlands of England

AIMS

To undertake a prospective point prevalence study of the prevalence of active Charcot neuro-inflammatory osteoarthropathy (Charcot disease) in a circumscribed part of England and to audit the time elapsing between disease onset and first diagnosis.

METHODS

The prevalence of active Charcot disease of the foot during a single month was assessed by specialist foot care teams at seven secondary care services in the East Midlands region of England.

RESULTS

A total of 90 cases were identified, representing 4.3 per 10 000 of the 205 033 total diabetes population of the region. The time elapsed from first presentation to any healthcare professional until diagnosis was also assessed. While the diagnosis was suspected or confirmed in one-third of patients within 2 weeks, it was not made for 2 months or more in 23 patients (24%).

CONCLUSIONS

Non-specialist professionals should have greater awareness of the existence of this uncommon complication of diabetes in the hope that earlier diagnosis will lead to lesser degrees of deformity.

A prognostic nomogram to predict overall survival in patients with platinum-sensitive recurrent ovarian cancer

BACKGROUND

Patients with platinum-sensitive recurrent ovarian cancer have variable prognosis and survival. We extend previous work on prediction of progression-free survival by developing a nomogram to predict overall survival (OS) in these patients treated with platinum-based chemotherapy.

PATIENTS AND METHODS

The nomogram was developed using data from the CAELYX in Platinum-Sensitive Ovarian Patients (CALYPSO) trial. Multivariate proportional hazards models were generated based on pre-treatment characteristics to develop a nomogram that classifies patient prognosis based on OS outcome. We also developed two simpler models with fewer variables and conducted model validations in independent datasets from AGO-OVAR Study 2.5 and ICON 4. We compare the performance of the nomogram with the simpler models by examining the differences in the C-statistics and net reclassification index (NRI).

RESULTS

The nomogram included six significant predictors: interval from last platinum chemotherapy, performance status, size of the largest tumour, CA-125, haemoglobin and the number of organ sites of metastasis (C-statistic 0.67; 95% confidence interval 0.65-0.69). Among the CALPYSO patients, the median OS for good, intermediate and poor prognosis groups was 56.2, 31.0 and 20.8 months, respectively. When CA-125 was not included in the model, the C-statistics were 0.65 (CALYPSO) and 0.64 (AGO-OVAR 2.5). A simpler model (interval from last platinum chemotherapy, performance status and CA-125) produced a significant decrease of the C-statistic (0.63) and NRI (26.4%, P < 0.0001).

CONCLUSIONS

This nomogram with six pre-treatment characteristics improves OS prediction in patients with platinum-sensitive ovarian cancer and is superior to models with fewer prognostic factors or platinum chemotherapy free interval alone. With independent validation, this nomogram could potentially be useful for improved stratification of patients in clinical trials and also for counselling patients.

Value of herpes simplex virus type-specific serology: a case report

Genital herpes, usually caused by herpes simplex virus type 2 (HSV-2), is one of the most common sexually transmitted diseases in humans. By contrast, intrauterine HSV-2 infections have been described rarely in the literature. Our report describes a case of neonate who was delivered after 30+2 gestational weeks by cesarean section. He presented with a respiratory distress syndrome resulting in broncho-pulmonary dysplasia. At the age of 6 weeks, a chorioretinal scar was detected. During the 4th month of age, the infant developed recurrent HSV-2 infection with nasal lesions. The retrospective type-specific serologic diagnosis revealed previous HSV-2 infection of the mother resulting in prenatal HSV-2 infection of the infant. In conclusion, intrauterine HSV-2 infections may be underrepresented since they may not be associated with severe congenital malformations and the diagnosis requires the use of HSV type-specific serologic methods not widely applied in microbiological laboratories.

Corrigendum: Progression-Free Survival in Advanced Ovarian Cancer: A Canadian Review and Expert Panel Perspective

In recent years, significant advances have been made in the management of metastatic colorectal cancer. Traditionally, an improvement in overall survival has been considered the “gold standard”—the most convincing measure of efficacy. However, overall survival requires larger patient numbers and longer follow-up and may often be confounded by other factors, including subsequent therapies and crossover. Given the number of active therapies for potential investigation, demand for rapid evaluation and early availability of new therapies is growing. Progression-free survival is regarded as an important measure of treatment benefit and, compared with overall survival, can be evaluated earlier, with fewer patients and no confounding by subsequent lines of therapy. The present paper reviews the advantages, limitations, and relevance of progression-free survival as a primary endpoint in randomized trials of metastatic colorectal cancer.

Distribution and Characterization of Iron in Implanted Silicon Carbide

Analytical electron microscopy (AEM) and Rutherford backscattering spectroscopy-ion channeling (RBS-C) have been used to characterize single crystal α-silicon carbide implanted at room temperature with 160 keV 57Fe ions to fluences of 1, 3, and 6×1016 ions/cm2. Best correlations among AEM, RBS, and TRIM calculations were obtained assuming a density of the amorphized implanted regions equal to that of crystalline SiC. No iron-rich precipitates or clusters were detected by AEM. Inspection of the electron energy loss fine structure for iron in the implanted specimens suggests that the iron is not metallically-bonded, supporting conclusions from earlier conversion electron Mössbauer spectroscopy (CEMS) studies. In-situ annealing surprisingly resulted in crystallization at 600°C with some redistribution of the implanted iron.

Grain-Boundary, Glassy-Phase Identification and Possible Artifacts

Specimen artifacts such as grain boundary grooving, surface damage of the specimen, and Si contamination are shown experimentally to arise from the ion milling used in the preparation of transmission electron microscopy specimens. These artifacts in polycrystalline, ceramic specimens can cause clean grain boundaries to appear to contain a glassy phase when the dark-field diffuse scattering technique, the Fresnel fringe technique, and analytical electron microscopy (energy dispersive spectroscopy) are used to identify glassy phases at a grain boundary. The ambiguity in interpereting each of these techniques due to the ion milling artifacts will be discussed from a theoretical view point and compared to experimental results obtained for alumina.

Chromium Distribution in CoCrTa/Cr Longitudinal Recording Media

The current study of CoCr12Ta4/Cr longitudinal recording media combines high resolution electron microscopy (HRTEM) with nanoprobe energy dispersive spectroscopy (EDS) and energy-filtered imaging (EFTEM) to correlate the Cr distribution with specific microstructural features. EFTEM images show Cr enrichment at grain boundaries, both random angle boundaries and 90° bicrystal boundaries. Cr segregation within grains is also observed in the elemental maps. This intragrain segregation often occurs at a series of defects that may define separately nucleated grains having 00 misorientation. Nanoprobe EDS measurements indicate that these defects contain localized concentrations of 25 to 30 % Cr. The random angle grain boundary Cr concentration occurs with a wide range, 19 to 36 at% (mean 22%) whereas the more crystallographically related 900 boundaries contain less Cr with less variation, 15 to 21 at% (mean 17% Cr). Composition profiles across grain boundaries using both nanoprobe EDS and EFTEM images show the full-width-half-maximum of the segregation to be approximately 4 nm, with Cr depleted regions next to the grain boundary having less than 7 at% Cr. The Ta concentration revealed no statistical evidence of segregation.

Interfacial Characterization with Spectrum-Lines and Multivariate Statistical Analysis

Changes in the electron energy-loss near-edge fine structure (ELNES) of the O-K and Co-L edges have been characterized in cobalt oxide in the vicinity of a boundary between periclase-(CoO) and spinel- (Co3O4) structured phases. The data were acquired with a conventional transmission electron microscope (CTEM) equipped with an imaging filter and operated in spectrum-line mode. Independent spectral features were identified by multivariate statistical analysis (MSA) of the raw data. The MSA of the spectrum-image acquired at the Co-L edge indicated a transition over ∼12 nm in the spectral features at the phase boundary. The variation of the ELNES at the O-K edge varied appreciably only in the interface region, whereas that at the Co-L edge also indicated subtle gradients in both phases adjacent to the interface area. These gradients are consistent with a change in the average oxidation state of the cobalt cations in the vicinity of the interface. A second independent component of the ELNES was also identified at the Co-L edge. Possible interpretations of this second component are discussed.

Pre-clinical evaluation of cyclin-dependent kinase 2 and 1 inhibition in anti-estrogen-sensitive and resistant breast cancer cells

BACKGROUND

Cellular proliferation, driven by cyclin-dependent kinases (CDKs) and their cyclin partners, is deregulated in cancer. Anti-estrogens, such as tamoxifen, antagonise estrogen-induced ERalpha transactivation of cyclin D1, resulting in reduced CDK4/6 activity, p27(Kip1)-mediated inhibition of CDK2 and growth arrest. We hypothesised that direct inhibition of CDK2 and CDK1 may overcome the major clinical problem of anti-estrogen resistance.

METHODS

The cellular effects of CDK2/1 siRNA knockdown and purine-based CDK2/1 inhibitors, NU2058 and NU6102, were measured in anti-estrogen-sensitive and resistant breast cancer cell lines.

RESULTS

CDK2 knockdown caused G1 accumulation, whereas CDK1 depletion caused G2/M slowing, and dual CDK1/2 depletion resulted in further G2/M accumulation and cell death in both anti-estrogen-sensitive and resistant cells, confirming CDK2 and CDK1 as targets for breast cancer therapy. In contrast to tamoxifen, which only affected hormone-sensitive cells, NU2058 and NU6102 reduced CDK2-mediated phosphorylation of pRb, E2F transcriptional activity and proliferation, ultimately resulting in cell death, in both anti-estrogen-sensitive and resistant cells. Both drugs caused G2/M arrest, reflective of combined CDK2/1 knockdown, with a variable degree of G1 accumulation.

CONCLUSION

These studies confirm the therapeutic potential of CDK2 and CDK1 inhibitors for cancer therapy, and support their use as an alternative treatment for endocrine-resistant breast cancer.

Detection of single atoms and buried defects in three dimensions by aberration-corrected electron microscope with 0.5-A information limit

The ability of electron microscopes to analyze all the atoms in individual nanostructures is limited by lens aberrations. However, recent advances in aberration-correcting electron optics have led to greatly enhanced instrument performance and new techniques of electron microscopy. The development of an ultrastable electron microscope with aberration-correcting optics and a monochromated high-brightness source has significantly improved instrument resolution and contrast. In the present work, we report information transfer beyond 50 pm and show images of single gold atoms with a signal-to-noise ratio as large as 10. The instrument's new capabilities were exploited to detect a buried Sigma3 {112} grain boundary and observe the dynamic arrangements of single atoms and atom pairs with sub-angstrom resolution. These results mark an important step toward meeting the challenge of determining the three-dimensional atomic-scale structure of nanomaterials.

Inhibition of double-strand break non-homologous end-joining by cisplatin adducts in human cell extracts

The effect of cis-diaminedichloroplatinum(II) (cisplatin) DNA damage on the repair of double-strand breaks by non-homologous end-joining (NHEJ) was determined using cell-free extracts. NHEJ was dramatically decreased when plasmid DNA was damaged to contain multiple types of DNA adducts, along the molecule and at the termini, by incubation of DNA with cisplatin; this was a cisplatin concentration-dependent effect. We investigated the effect a single GTG cisplatination site starting 10 bp from the DNA termini would have when surrounded by the regions of AT-rich DNA which were devoid of the major adduct target sequences. Cisplatination of a substrate containing short terminal 13-15 bp AT-rich sequences reduced NHEJ to a greater extent than that of a substrate with longer (31-33 bp) AT-rich sequences. However, cisplatination at the single GTG site within the AT sequence had no significant effect on NHEJ, owing to the influence of additional minor monoadduct and dinucleotide adduct sites within the AT-rich region and owing to the influence of cisplatination at sites upstream of the AT-rich regions. We then studied the effect on NHEJ of one cis-[Pt(NH3)2{d(GpTpG)-N7(1),-N7(3)} [abbreviated as 1,3-d(GpTpG)] cisplatin adduct in the entire DNA molecule, which is more reflective of the situation in vivo during concurrent chemoradiation. The presence of a single 1,3-d(GpTpG) cisplatin adduct 10 bases from each of the two DNA ends to be joined resulted in a small (30%) but significant decrease in NHEJ efficiency. This process, which was DNA-dependent protein kinase and Ku dependent, may in part explain the radiosensitizing effect of cisplatin administered during concurrent chemoradiation.

Preliminary linkage map of the turkey (Meleagris gallopavo) based on microsatellite markers

The turkey is an agriculturally important species for which, until now, there is no published genetic linkage map based on microsatellite markers--still the markers most used in the chicken and other farm animals. In order to increase the number of markers on a turkey genetic linkage map we decided to map new microsatellite sequences obtained from a GT-enriched turkey genomic library. In different chicken populations more than 35-55% of microsatellites are polymorphic. In the turkey populations tested here, 43% of all turkey primers tested were found to be polymorphic, in both commercial and wild type turkeys. Twenty linkage groups (including the Z chromosome) containing 74 markers have been established, along with 37 other unassigned markers. This map will lay the foundations for further genetic mapping and the identification of genes and quantitative trait loci in this economically important species. Genome comparisons, based on genetic maps, with related species such as the chicken would then also be possible. All primer information, polymerase chain reaction (PCR) conditions, allele sizes and genetic linkage maps can be viewed at http://roslin.thearkdb.org/. The DNA is also available on request through the Roslin Institute.

Optimal management for surgically Stage 1 serous cancer of the uterus

OBJECTIVE

To describe the outcomes of patients who have undergone well-conducted surgery and found to have Stage 1 serous uterine cancer.

METHODS

This retrospective cohort study includes women who have been treated for Stage 1 serous cancer of the uterus from 1985 to 2001. Cases were included from the regional cancer centers in Hamilton, London, Sunnybrook Toronto and Cancer Care Manitoba.

RESULTS

Forty-three women met the inclusion criteria: Complete surgical staging (n = 27), surgery followed by pelvic radiation therapy (n = 4), surgery followed by whole abdominal radiation therapy (n = 6), surgery followed by adjuvant chemotherapy (n = 6). Patient age or depth of invasion did not influence survival. Progression free interval was 22 months (SD = 14.29). Recurrence rate was highest for adjuvant chemotherapy (66%). Survival was assessed by treatment modality and a statistically significant poorer survival was seen in the adjuvant chemotherapy group (OR 17.5; 95% CI 1.3-227.6). No comment can be made on a superior treatment regimen given the small numbers in each treatment strata.

CONCLUSION

This study supports the findings of others in the literature. In a group of patients where surgical staging shows limited disease (i.e., surgically Stage 1 disease), then surgery alone appears to be adequate treatment.

Pulmonary arterial dilation by inhaled NO: arterial diameter, NO concentration relationship

The objective of this study was to determine the nitric oxide (NO) concentration and vessel diameter dependence of the pulmonary arterial dilation induced by inhaled NO. Isolated dog lung lobes were situated between a microfocal X-ray source and X-ray detector and perfused with either blood or plasma. Boluses of radiopaque contrast medium were injected into the lobar artery under control conditions, when the pulmonary arteries were constricted by infusion of serotonin and when the serotonin infusion was accompanied by inhalation of from 30 to 960 parts/million NO. Arterial diameter measurements were obtained from X-ray images of vessels having control diameters in the 300- to 3,400-microm range. Serotonin constricted the vessels throughout the size range studied, with an average decrease in diameter of approximately 20%. The fractional reversal of the serotonin-induced constriction by inhaled NO was directly proportional to inhaled NO concentration, inversely proportional to vessel size, and greater with plasma than with blood perfusion in vessels as large as 3 mm in diameter. The latter indicates that intravascular hemoglobin affected the bronchoalveolar-to-arterial luminal NO concentration gradient in fairly large pulmonary arteries. The data provide information regarding pulmonary arterial smooth muscle accessibility to intrapulmonary gas that should be useful as part of the database for modeling the communication between intrapulmonary gas and pulmonary arterial smooth muscle cells in future studies.

Promoting patient partnership in wound care

Involving patients in their care is a key component of the NHS plan and clinical governance (Department of Health, 1999a). Involvement is enhanced through nurse-patient relationships which are based on partnership in which the patient's viewpoint is given equal weight to that of the practitioner. In the management of wounds, this may be complex due to conflict between clinically effective treatment and a patient's wish. High quality care relies on a holistic assessment of the patient and a negotiated care plan which is implemented and evaluated in order to judge the effectiveness of care.

Assess, negotiate, treat: community prescribing for chronic wounds

The cost of prescribing wound-care products in general practice in 1999 exceeded 95 million (Department of Health (DoH), 1999a). However, there is a lack of randomized controlled trials to assess the effectiveness of wound-care products (National Prescribing Centre, 1999a) and there is evidence that non-effective treatments are being prescribed (DoH, 1999a). Use of the prescribing pyramid, as taught during nurse prescribing courses, may help community nurses justify their decisions and assess their wound-care practices. Wounds commonly encountered in the community include pressure sores, leg ulcers, fungating wounds and cavity wounds. The ideal choice of product is one that allows moist wound healing, is cost effective, clinically effective and acceptable to the patient.

Preventing unnecessary suffering: an audit of a leg ulcer clinic

Unnecessary patient suffering and increased costs in leg ulcer care were reported in an Effective Health Care bulletin (NHS Centre for Reviews and Dissemination (NHSCRD), 1997). Follow-up assessment of patients with a history of venous ulceration has beneficial effects for patients' quality of life, and for effective and efficient management of resources for community nurses. This article describes the process of implementing evidence-based practice in a leg ulcer clinic in South London within existing resources, which resulted in the successful prevention of leg ulcer recurrence.

Glucose transport regulation by p210 Bcr-Abl in a chronic myeloid leukaemia model

The regulation of nutrient transport by both cytokines and oncogenes has been linked to haemopoietic cell survival. In this study, we found that activation of Bcr--Abl protein tyrosine kinase was associated with the stimulation of glucose transport in the multipotent haemopoietic cell line FDCP-mix, a cell model for chronic-phase chronic myeloid leukaemia (CML). Bcr--Abl upregulation of glucose transport was mediated by phosphatidylinositol-3-kinase. The observation that Bcr--Abl can regulate glucose transport in a CML cell model raises the possibility that glucose transport regulation may have a role to play in the aberrant survival of stem cells in the chronic phase of CML.

Developing an activity measuring system in district nursing

The current measurement of face-to-face contacts for calculating district nursing activity is inadequate for district nurses, their managers, and purchasers. With the growing emphasis on health outcomes, a measure is needed which demonstrates health gain and effectiveness, yet which does not place an additional burden for data collection on nurses' time. This article describes the preliminary findings of a project carried out in East Berkshire which suggest that such a measure is possible, and that effective care, including illness prevention, can be demonstrated. It shows that existing computer software can meet the demands for the measurement of health gain. While these are positive findings, district nurses, service managers and commissioners will need to allocate time to understand and interpret the data before drawing conclusions about the use of activity measurement in workforce planning, service costing and the effectiveness of district nursing interventions.

A health visitor for older people in an accident and emergency department

Published studies indicate that older people have special needs on discharge from accident and emergency (A&E) departments that are not always fully met. The literature reflects that although a significant proportion of older people have a decrease in functional independence and an increased need for services following discharge from A&E, social and functional assessment by A&E staff can be inadequate, as can the arrangement of follow-up community services. As part of a wider study into the organization of care for older people in A&E, a health visitor for older people was funded to work part-time in the A&E department of a large NHS Trust. The health visitor identified potential clients through reviewing the A&E documentation of patients aged 75 years or over discharged directly from A&E. Telephone calls or home visits were used to follow up those individuals deemed to be vulnerable by the health visitor. Interventions included health education, referral to other agencies and patient or family counselling. None of the clients followed up by the health visitor (n = 212) had been referred by A&E to a specialist in gerontology, which suggests that these clients would otherwise not have received the potential benefit of specialist intervention. The pilot study described here highlights a number of practical issues in relation to the health visitor post for older people in A&E, including the importance of dedicated office space and access to a telephone. Data collected during the study, plus the positive evaluation of the role by a small group of A&E staff confirm the claims made in other studies (e.g. Runciman et al, 1996) that health visitors for older people may be of value in meeting the post-discharge needs of these people.

The 5-hydroxytryptamine6 receptor-selective radioligand [3H]Ro 63-0563 labels 5-hydroxytryptamine receptor binding sites in rat and porcine striatum

Ro 63-0563 [4-amino-N-(2,6 bis-methylamino-pyridin-4-yl)-benzene sulfonamide] is a high affinity 5-hydroxytryptamine6 (HT6) receptor antagonist with more than 100-fold selectivity for the 5-HT6 receptor compared with 69 other receptors and binding sites. The present study describes the properties of [3H]Ro 63-0563, the first selective 5-HT6 receptor radioligand. Specific binding of [3H]Ro 63-0563 (nonspecific binding defined in the presence of 10 microM methiothepin) to recombinant rat and human 5-HT6 receptors was saturable, rapid, and reversible with equilibrium dissociation constants (Kd) of 6.8 nM and 4.96 nM, respectively. The pharmacological profile of the rat 5-HT6 receptor labeled with [3H]Ro 63-0563 (methiothepin > D-lysergic acid diethylamide > clozapine approximately Ro 63-0563 > lisuride > ergotamine approximately Ro 04-6790 > 5-HT > amitriptyline approximately metergoline approximately mianserin approximately ritanserin > methysergide > mesulergine) was similar to that obtained by using either [3H]D-lysergic acide diethylamide or [3H]5-HT as radioligand. In equilibrium binding studies with rat striatal membranes, [3H]Ro 63-0563 labeled a single binding site with Kd and Bmax values of 11. 7 nM and 175 fmol/mg protein, respectively. In porcine striatal membranes, [3H]Ro 63-0563 also labeled a single binding site with Kd and Bmax values of 8.0 nM and 130 fmol/mg protein, respectively. The affinities of 14 5-HT6 receptor ligands at this binding site were similar to those found for the recombinant rat and human 5-HT6 receptor, which suggested the presence of 5-HT6 receptors in porcine striatum.

Memories of a WHO expert in midwifery

Much of the health infrastructure we now take for granted is the result of determined efforts made in the 1960s and 1970s. The objective was relatively clear: to help build up strong national health systems. But to do that an uncommon amount of energy and imagination was needed.