Vascular endothelial growth factor receptors in osteoclast differentiation and function

Osteoclasts are derived from haematopoietic stem cell precursors of the monocyte/macrophage cell lineage, through interaction with factors that are believed to include M-CSF and RANKL. VEGF is a proangiogenic cytokine that has been shown to promote osteoclast differentiation and survival. In this study, we assessed the role of VEGF and its receptors in osteoclastogenesis, in vitro, by culturing osteoclast precursors in the presence of VEGF, VEGF receptor-specific ligands, and blocking antibodies to VEGF receptors. Activation of VEGFR1 in the presence of RANKL induces osteoclast differentiation. Stimulating the receptors individually induced increased resorption by osteoclasts compared to controls but not to the level observed when stimulating both receptors simultaneously. We have shown that VEGF induces osteoclast differentiation through its action on VEGFR1. The way in which VEGF mediates its effect on mature osteoclast activity, however, may be through its interaction with both receptor subtypes.

Medical ethics in contemporary clinical practice

This review article describes and analyzes ethical issues in medical practice, particularly those issues encountered by physicians in their relationships with their patients. These relationships often involve ethical conflicts between 2 or more interests, which physicians need to recognize and resolve. The article deals with 4 topics in clinical practice in which ethical conflicts occur: physicians' duty of confidentiality in a digital environment, their responsibilities for dealing with abuses of the human rights of patients, their role in clinical research, and their relationships with commercial enterprises. The ethical policies of the World Medical Association provide the basis for determining appropriate physician conduct on these matters. The article concludes with reflections on the need for international standards of medical ethics.

Impaired forearm rotation after tension-band-wiring fixation of olecranon fractures: evaluation of the transcortical K-wire technique

The tension-band-wiring technique is a well-accepted method of internal fixation of olecranon fractures. In addition, it is suggested that transcortical placement of the k-wires results in lower rates wire migration. We encountered two clinical cases in which transcortical placement of the k-wires led to impairment of forearm rotation. An anatomic study was conducted to study the effect of transcortical wire placement to avoid similar future complications. Using specimens from 10 embalmed cadavers, we found that transcortical wires inserted in <30 degrees of ulnar angulation in the coronal plane to the medial ridge of the olecranon, impinged on the radial neck, supinator muscle, or biceps tendon. This was avoided in all 10 specimens when the wires were inserted, with the forearm in supination, at 30 degrees of ulnar angulation. We recommend this technique to be adopted to avoid forearm rotation impairment.

A comparison of functional, patient-based scores in subacromial impingement

The goal of this study was to compare the Oxford Shoulder Score (OSS), the Shoulder Pain and Disability Index (SPADI), and the Short Form 36 (SF-36) for their correlation, agreement, sensitivity to change, and test-retest reliability in patients with a clinical diagnosis of subacromial impingement. All patients attending a specialist subacromial impingement clinic over a 6-month period completed the OSS, SPADI, and SF-36 at each visit. A total of 323 sets of observations were recorded in 110 patients. The first 38 of these patients were also sent the questionnaires to complete before their visit. There was good correlation between the OSS and SPADI scores (correlation coefficient = 0.85) and good agreement between the scores on each scale (weighted kappa = 0.79). The correlation with total SF-36 was poor (0.37 for OSS and 0.26 for SPADI). The OSS and SPADI showed good effect sizes compared with the total SF-36 score and good test-retest reliability. These data support the use of the OSS or SPADI in patients with subacromial impingement.

Incorporating ethics in priority setting: a case study of a regional health board in Canada

The authors were involved in developing an ethical framework to assist the Queens Region Board (Prince Edward Island, Canada) set priorities in health and health care. Two and one half years after the adoption of this framework, the authors undertook an evaluation of the framework. This paper will discuss: (a) the historical background of regionalization in Canada, and in particular the circumstances leading up to the institution of regional boards in Prince Edward Island; (b) the sorts of ethical issues facing the Queens Regional Board; (c) issues arising in connection with the use and development of ethics frameworks for managing ethical issues in priority setting; (d) the framework adopted by the Queens Board and the process that led to its development; (e) issues arising as concerns implementation of the framework; (f) questions and issues pertinent to other boards and bodies considering similar initiatives.

Vascular endothelial growth factor acts as an osteolytic factor in breast cancer metastases to bone

Vascular endothelial growth factor (VEGF) is a proangiogenic cytokine that is expressed highly in many solid tumours often correlating with a poor prognosis. In this study, we investigated the expression of VEGF and its receptors in bone metastases from primary human breast tumours and further characterised its effects on osteoclasts in vitro. Breast cancer metastases to bone were immunohistochemically stained for VEGF, its receptors VEGFR1 and 2 (vascular endothelial growth factor receptor 1 and 2), demonstrating that breast cancer metastases express VEGF strongly and that surrounding osteoclasts express both VEGFR1 and VEGFR2. RAW 264.7 cells (mouse monocyte cell line) and human peripheral blood mononuclear cells (PBMCs) were cultured with VEGF, RANKL and M-CSF. VEGF and RANKL together induced differentiation of multinucleated, tartrate-resistant acid phophatase (TRAP)-positive cells in similar numbers to M-CSF and RANKL. The PBMCs were also able to significantly stimulate resorption of mineralised matrix after treatment with M-CSF with RANKL and VEGF with RANKL. We have shown that VEGF in the presence of RANKL supports PBMC differentiation into osteoclast-like cells, able to resorb substrate. Vascular endothelial growth factor may therefore play a role in physiological bone resorption and in pathological situations. Consequently, VEGF signalling may be a therapeutic target for osteoclast inhibition in conditions such as tumour osteolysis.

Outcome following Bankart repair for shoulder instability 1998-2002 using a subjective patient based shoulder questionnaire (Oxford)

Bankart repair for shoulder instability has been performed by the senior author since 1998. We employ a modification of the technique as described by Rowe et al., using suture anchors but without a coracoid osteotomy. If inferior instability was present this procedure was combined with a capsular shift. We performed a retrospective case note review and postal questionnaire incorporating the Oxford Instability Score (OIS) on all patients. Fifty Bankart repairs were performed in the study period, three patients had further dislocations and three patients had ongoing symptoms of instability. Response rate to the questionnaire was 62%. Mean OIS following primary stabilisation was 21.7 (possible scores from 12-excellent to 60-poor). OIS following Bankart stabilisation of the shoulder has not been previously reported. These results compare favourably to original scores published by Dawson et al. (1999) who included both patients treated by surgery or physiotherapy.

Measles elimination in Italy: projected impact of the National Elimination Plan

A mathematical model was used to evaluate the impact of the Italian Measles National Elimination Plan (NEP), and possible sources of failure in achieving its targets. The model considered two different estimates of force of infection, and the possible effect on measles transmission of the current Italian demographic situation, characterized by a below-replacement fertility. Results suggest that reaching all NEP targets will allow measles elimination to be achieved. In addition, the model suggests that achieving elimination by reaching a 95 % first-dose coverage appears unlikely; and that conducting catch-up activities, reaching high vaccination coverage, could interrupt virus circulation, but could not prevent the infection re-emerging before 2020. Also, the introduction of the second dose of measles vaccine seems necessary for achieving and maintaining elimination. Furthermore, current Italian demography appears to be favourable for reaching elimination.

The pre-vaccination regional epidemiological landscape of measles in Italy: contact patterns, effort needed for eradication, and comparison with other regions of Europe

Background

Strong regional heterogeneity and generally sub-optimal rates of measles vaccination in Italy have, to date, hampered attainment of WHO targets for measles elimination, and have generated the need for the new Italian National Measles Elimination Plan. Crucial to success of the plan is the identification of intervention priorities based upon a clear picture of the regional epidemiology of measles derived from the use of data to estimate basic parameters. Previous estimates of measles force of infection for Italy have appeared anomalously low. It has been argued elsewhere that this results from Italian selective under-reporting by age of cases and that the true measles force of infection in Italy is probably similar to that of other European countries. A deeper examination of the evidence for this conjecture is undertaken in the present paper.

Methods

Using monthly regional case notifications data from 1949 to the start of vaccination in 1976 and notifications by age from 1971–76, summary equilibrium parameters (force of infection (FOI), basic reproductive ratio (R₀) and critical vaccination coverage (p_c)) are calculated for each region and for each of 5 plausible contact patterns. An analysis of the spectra of incidence profiles is also carried out. Finally a transmission dynamics model is employed to explore the correspondence between projections using different estimates of force of infection and data on seroprevalence in Italy.

Results

FOI estimates are lower than comparable European FOIs and there is substantial regional heterogeneity in basic reproductive ratios; certain patterns of contact matrices are demonstrated to be unfeasible. Most regions show evidence of 3-year epidemic cycles or longer, and compared with England & Wales there appears to be little synchronisation between regions. Modelling results suggest that the lower FOI estimated from corrected aggregate national data matches serological data more closely than that estimated from typical European data.

Conclusion

Results suggest forces of infection in Italy, though everywhere remaining below the typical European level, are historically higher in the South where currently vaccination coverage is lowest. There appears to be little evidence to support the suggestion that a higher true force of infection is masked by age bias in reporting.

In vivo mammary tumourigenesis in the Sprague-Dawley rat and microdosimetric correlates

Standard methods for risk assessments resulting from human exposures to mixed radiation fields in Space consisting of different particle types and energies rely upon quality factors. These are generally defined as a function of linear energy transfer (LET) and are assumed to be proportional to the risk. In this approach, it is further assumed that the risks for single exposures from each of the radiation types add linearly. Although risks of cancer from acute exposures to photon radiations have been measured in humans, quality factors for protons and ions of heavier atomic mass are generally inferred from animal and/or cellular data. Because only a small amount of data exists for such particles, this group has been examining tumourigenesis initiated by energetic protons and iron ions. In this study, 741 female Sprague-Dawley rats were irradiated or sham irradiated at approximately 60 days of age with 250 MeV protons, 1 GeV/nucleon iron ions or both protons and iron ions. The results suggest that the risk of mammary tumours in the rats sequentially irradiated with 1 GeV/nucleon 56Fe ions and 250 MeV protons is less than additive. These data in conjunction with earlier results further suggest that risk assessments in terms of only mean LETs of the primary cosmic rays may be insufficient to accurately evaluate the relative risks of each type of particle in a radiation field of mixed radiation qualities.

Psychiatric comorbidities in patients with Parkinson disease and psychosis

OBJECTIVE

To determine the prevalence and impact of comorbid psychiatric disturbances in Parkinson disease (PD) patients with psychosis.

METHODS

Subject data were derived from a research database of 116 PD patients participating in standardized motor, cognitive, psychiatric, and caregiver assessments.

RESULTS

There were 25 patients (22%) with psychosis manifest as hallucinations (n = 9), delusions (n = 1), or hallucinations and delusions (n = 15) and 25 patients (22%) who had no current or past psychiatric comorbidities (PDN). In the psychotic group, 44% had psychosis only (PSY), and 56% had psychosis plus at least one other comorbid psychiatric disturbance (PSY+), including depressive disorders (71%), anxiety disorders (21%), apathetic syndromes (14%), and delirium (14%). There were no differences in age, sex, education, or age onset or duration of PD among the PSY, PSY+, and PDN groups. Both psychotic groups had greater motor, functional, and frontal cognitive deficits and increased caregiver burden scores relative to PDN. PSY+ showed greater global and selective cognitive deficits compared to PDN. Psychosis was a primary predictor of caregiver burden, whereas depressive symptoms indirectly enhanced motor impairments.

CONCLUSIONS

Nonpsychotic psychiatric disturbances, especially affective disturbances, are common comorbidities in PD patients with psychosis and warrant clinical attention to reduce morbidity and caregiver distress.

The ethics activities of the World Medical Association

Since its formation in 1947, the World Medical Association (WMA) has been a leading voice in international medical ethics. The WMA's principal ethics activity over the years has been policy development on a wide variety of issues in medical research, medical practice and health care delivery. With the establishment of a dedicated Ethics Unit in 2003, the WMA's ethics activities have intensified in the areas of liaison, outreach and product development. Initial priorities for the Ethics Unit have been the review of paragraph 30 of the Declaration of Helsinki, the expansion of the Ethics Unit section of the WMA website and the development of an ethics manual for medical students everywhere.

Realistic population dynamics in epidemiological models: the impact of population decline on the dynamics of childhood infectious diseases. Measles in Italy as an example

Most contributions in the field of mathematical modelling of childhood infectious diseases transmission dynamics have focused on stationary or exponentially growing populations. In this paper an epidemiological model with realistic demography is used to investigate the impact of the non-equilibrium conditions typical of the transition to sustained below replacement fertility (BRF) recently observed in a number of western countries, upon the transmission dynamics of measles. The results depend on the manner we model the relation between the (changing) age distribution of the population and contacts. Under some circumstances the transitional ageing phase typical of BRF populations might complexly interact with epidemiological variables leading to (i) a substantial reduction in the amount of vaccination effort required for eliminating the disease; (ii) a significant magnification of the perverse impact of vaccination in terms of the burden of severe age related morbidity.

Isolation and synthesis of shark-repelling saponins

Saponins are complex compounds that are composed of a saccharide attached to a steroid or triterpene. They are natural surfactants, or detergents. Several important biological effects have been ascribed to saponins. They have been isolated from a great number of terrestrial plants. In the animal kingdom they are found in most sea cucumbers and starfish, whereas they are found only rarely in alcyonarians, gorgonians, sponges, and as shark-repelling compounds in fish. The present review deals with the isolation and some syntheses of the shark-repelling saponins mosesins-1 to -5 and pavoninins-1 to -6 obtained from the fish species Pardachirus.

Factors influencing atopic dermatitis-a questionnaire survey of schoolchildren's perceptions

BACKGROUND

Although there is growing knowledge about factors that may predispose to the onset of atopic dermatitis (AD), little is known about factors which may exacerbate existing disease. AD sufferers and those involved in the management of the disease are often aware of factors that influence its course and severity. However, there is little available evidence on the distribution and relative importance of such factors, and what information exists is derived from selected groups such as hospital patients and may not therefore be representative of the AD population as a whole.

OBJECTIVES

To determine the distribution and relative importance of 19 potential exacerbating and relieving factors as perceived by a population-based sample of schoolchildren with AD.

METHODS

A questionnaire was used to identify all children with AD in years 8 and 9 (12-14-year-olds) from eight comprehensive schools across Wales. These individuals were then requested to complete a supplementary questionnaire which asked them to state for each of 19 factors whether (i) it makes their eczema better, (ii) it makes their eczema worse, (iii) it has no effect, or (iv) they do not know its effects.

RESULTS

Almost 10% (250 of 2501) of children surveyed were considered to have AD, and 90% (225 of 250) of these completed the supplementary questionnaire. Most AD sufferers found that none to two factors relieve their symptoms whilst none to five factors exacerbate them. Sweating from exercise, fabrics (especially wool) and hot weather were the three most common exacerbators, affecting 41.8%, 40% and 39.1%, respectively, of AD responders. The three key relievers were steroid creams (22.2% of AD responders), moisturizers/makeup (16.4%) and medicines/tablets (13.8%). Almost 60% of respondents believed foods have no effect on their symptoms. There was also evidence to suggest that 12.4% (28 of 225) of participants may use creams which they are not aware contain steroids.

CONCLUSIONS

These findings shed light on the relative perceived importance of factors such as food, aeroallergens, sweat, climate, illness, stress and therapies for the course of AD in a representative population sample of AD sufferers. Such information might be explored during clinical consultations given the increasing participation of sufferers and their carers in the management of this chronic disease. These findings also form the basis of hypothesis generation for future analytical studies.

Intracellular oxidation by human glioma cell populations: effect of arachidonic acid

Arachidonic acid (AA) and Gamma linolenic acid have been shown to limit glioma cell growth, stimulate apoptosis and lipid peroxidation. However, brain tumours are characterised by cellular heterogeneity and responding cell populations have not been identified. Brain tumour samples from patients were disaggregated. In cell preparations from 7 gliomas, reactive oxygen species (ROS), morphology and plasma membrane integrity were monitored +/-18-36 microM AA for 15-120 min using flow cytometry. Basal oxidative activity related to cell size/morphology, small granular cells showed lower activity. AA stimulation of ROS formation depended on cell size/morphology. Large, less granular cells showed greater AA stimulation. In 17 gliomas, GFAP immunofluorescence was demonstrated in larger cell populations. The large GFAP positive cell population with low side scatter was the highest responding cell population, suggesting selective tumour cell sensitivity to AA induced ROS formation. ROS may have a role in AA induced cell death and anti-tumour activity of AA in glioma.

Ageing populations and childhood infections: the potential impact on epidemic patterns and morbidity

BACKGROUND

Population decline, arising from below replacement fertility and possibly giving rise to substantial changes in age distribution, is a feature of many industrialized developed countries; Italy is one of the most notable European examples. The potential influence of this phenomenon on prevalence of chronic non-infectious disease is well known, but little attention to date has been paid to the impact on severe disease due to childhood infections in those cases where control is insufficient to achieve elimination.

METHODS

A transmission dynamics model incorporating realistic demography is used to investigate the possible impact of population decline and ageing and suboptimal vaccination uptake on the age distribution of incidence of measles infection and of consequent mortality. Data from Italy is used to parameterize the model.

RESULTS

Population ageing in the absence of vaccination is shown to reduce per capita incidence of infection but also to increase average and upper quartile ages at infection. The effect is substantially enhanced by significantly suboptimal vaccination uptake, when disease-induced mortality has, for a period, the potential to exceed that in the absence of vaccination.

CONCLUSIONS

Although a substantially increased burden from chronic non-infectious disease has frequently been proposed as a consequence of population decline, there is also potential for an increase in morbidity and mortality from measles and other childhood infectious diseases, particularly where vaccine uptake is substantially below the optimum. Rubella is highlighted as a particular cause for concern. This work also has implications for less-developed countries.

Synthesis and intramolecular reactions of trans-cyclohexyl-1,2-bisacrylate

Photocycloaddition of dimethyl cyclobut-1-ene-1,2-dicarboxylate (1) with cyclohexene (7) afforded two photoadducts 8 and 9 in 44% and 28% yields, respectively. Spontaneous thermal isomerization of 8 gave (4Z,10Z)-dimethyl cyclodeca-4,10-diene-1,4-dicarboxylate (10), which subsequently isomerized to produce trans-1,2-cyclohexanebis-alpha-acrylic acid dimethyl ester 11. Hydride reduction of the bisacrylate 11 gave the trans-octahydro-1H-inden-2-ols 12a and 15 via a novel, stereoselective, intramolecular reaction. Reaction of the bisacrylate 11 with methyllithium afforded the bis-tertiary alcohol 16. In contrast, lithium dimethylcuprate reacted with the bisacrylate 11 to give the trans-hexahydro-1H-inden-2-one 17 in high yield via a novel, stereoselective, intramolecular reaction.

Reducing atrazine losses: water quality implications of alternative runoff control practices

Water quality is being affected by herbicides, some allegedly harmful to human health. Under scrutiny is atrazine (1-chloro-3-ethylamino-5-isopropylamino-2,4,6-triazine), a commonly used herbicide in corn (Zea mays L.) and sorghum [Sorghum bicolor (L.) Moench] production. Concentrations of soluble and adsorbed atrazine losses sometimes exceed the safe drinking water standard of 3 microg L(-1) established by the USEPA. This study assesses the protective implications of runoff control structures and alternative crop farming practices to minimize atrazine losses. Using a computerized simulation model, APEX, the following four practices were the most effective with respect to the average atrazine loss as a percent of the amount applied: (i) constructing sediment ponds, 0.09%; (ii) establishing grass filter strips, 0.14%; (iii) banding a 25% rate of atrazine, 0.40%; and (iv) constructing wetlands, 0.45%. Other atrazine runoff management options, including adoption of alternative tillage practices such as conservation and no-till as well as splitting applications between fall and spring, were marginally effective.

α-Hydroxylation at C-15 and C-16 in Cholesterol: Synthesis of (25R)-5α-Cholesta-3β,15α,26-triol and (25R)-5α-Cholesta-3β,16α,26-triol from Diosgenin

[reaction: see text] (25R)-5alpha-cholesta-3beta,16alpha,26-triol 7b and (25R)-5alpha-cholesta-3beta,15alpha,26-triol 10b were synthesized, via (25R)-5alpha-cholesta-3beta,16beta,26-triol 5a, from diosgenin 3 in 52% yield over six steps and 47% yield over eight steps, respectively. An efficient method for inversion of a C-16beta hydroxyl to the C-16alpha position and a short method for transposition of a C-16beta hydroxyl to the C-15alpha position via the unexpected beta-reduction of a C-15 ketone in a steroid are reported.