Dopamine neurons drive spatiotemporally heterogeneous striatal dopamine signals during learning

Environmental cues, through Pavlovian learning, become conditioned stimuli that invigorate and guide animals toward acquisition of rewards. Dopamine neurons in the ventral tegmental area (VTA) and substantia nigra (SNC) are crucial for this process. Dopamine neurons are embedded in a reciprocally connected network with their striatal targets, the functional organization of which remains poorly understood. Here, we investigated how learning during optogenetic Pavlovian cue conditioning of VTA or SNC dopamine neurons directs cue-evoked behavior and shapes subregion-specific striatal dopamine dynamics. We used a fluorescent dopamine biosensor to monitor dopamine in the nucleus accumbens (NAc) core and shell, dorsomedial striatum (DMS), and dorsolateral striatum (DLS). We demonstrate spatially heterogeneous, learning-dependent dopamine changes across striatal regions. While VTA stimulation evoked robust dopamine release in NAc core, shell, and DMS, cues predictive of this activation preferentially recruited dopamine release in NAc core, starting early in training, and DMS, late in training. Corresponding negative prediction error signals, reflecting a violation in the expectation of dopamine neuron activation, only emerged in the NAc core and DMS, and not the shell. Despite development of vigorous movement late in training, conditioned dopamine signals did not similarly emerge in the DLS, even during Pavlovian conditioning with SNC dopamine neuron activation, which elicited robust DLS dopamine release. Together, our studies show broad dissociation in the fundamental prediction and reward-related information generated by different dopamine neuron populations and signaled by dopamine across the striatum. Further, they offer new insight into how larger-scale plasticity across the striatal network emerges during Pavlovian learning to coordinate behavior.

Ketone bodies in right ventricular failure: A unique therapeutic opportunity

Background

Ketone bodies are pleotropic metabolites that play important roles in multiple biological processes ranging from bioenergetics to inflammation regulation via suppression of the NLRP3 inflammasome, and epigenetic modifications. Ketone bodies are elevated in left ventricular failure (LVF) and multiple approaches that increase ketone concentrations exert advantageous cardiac effects in rodents and humans. However, the relationships between ketone bodies and right ventricular failure (RVF) are relatively unexplored.

Methods

51 PAH patients were dichotomized into preserved or impaired RV function based on a cardiac index of 2.2 L/min/m2. Impaired RV function patients were further segmented into intermediate or severe RV dysfunction based on a right atrial pressure of 8 mm Hg. Serum ketone bodies acetoacetate (AcAc) and beta-hydroxybutyrate (βOHB) were quantified using ultra performance liquid chromatography and mass spectrometry. In rodent studies, male Sprague Dawley rats were assigned to three groups: control (saline injection), monocrotaline (MCT) standard chow diet (MCT-Standard), and MCT ketogenic diet (MCT-Keto). Immunoblots and confocal microscopy probed macrophage NLRP3 activation in RV extracts and sections. RV fibrosis was determined by Picrosirus Red. Echocardiography evaluated RV function. Pulmonary arteriole remodeling was assessed from histological specimens.

Results

Human RVF patients lacked a compensatory ketosis as serum AcAc and βOHB levels were not associated with hemodynamic, echocardiographic, or biochemical measures of RV dysfunction. In rodent studies, AcAc and βOHB levels were also not elevated in MCT-mediated RVF, but the ketogenic diet significantly increased AcAc and βOHB levels. MCT-Keto exhibited suppressed NLRP3 activation with a reduction in NLRP3, ASC (apoptosis-associated speck-like protein), pro-caspase-1, and interleukin-1 beta on immunoblots. Moreover, the number of ASC-positive macrophage in RV sections was reduced, RV fibrosis was blunted, and RV function was augmented in MCT-Keto rats.

Conclusion

The ketogenic response is blunted in pulmonary arterial hypertension (PAH) patients with RVF. In the MCT rat model of PAH-mediated RVF, a dietary-induced ketosis improves RV function, suppresses NLRP3 inflammasome activation, and combats RV fibrosis. The summation of these data suggest ketogenic therapies may be particularly efficacious in RVF, and therefore future studies evaluating ketogenic interventions in human RVF are warranted.

Ketone Bodies in Right Ventricular Failure: A Unique Therapeutic Opportunity

Ketone bodies are pleotropic metabolites that play important roles in multiple biological processes ranging from bioenergetics to inflammation regulation via suppression of the NLRP3 inflammasome, and epigenetic modifications. Ketone bodies are elevated in left ventricular failure (LVF) and multiple approaches that increase ketone concentrations exert advantageous cardiac effects in rodents and humans. However, the relationships between ketone bodies and right ventricular failure (RVF) are relatively unexplored. Moreover, the cardioprotective properties of ketones in preclinical RVF are unknown. Here, we show a compensatory ketosis is absent in pulmonary arterial hypertension (PAH) patients with RVF. In the monocrotaline (MCT) rat model of PAH-mediated RVF, a dietary-induced ketosis improves RV function, suppresses NLRP3 inflammasome activation, and combats RV fibrosis. The summation of these data suggest ketogenic therapies may be particularly efficacious in RVF, and therefore future studies evaluating ketogenic interventions in human RVF are warranted.

Pulmonary Arterial Hypertension Patients Have a Proinflammatory Gut Microbiome and Altered Circulating Microbial Metabolites

Rationale: Inflammation drives pulmonary arterial hypertension (PAH). Gut dysbiosis causes immune dysregulation and systemic inflammation by altering circulating microbial metabolites; however, little is known about gut dysbiosis and microbial metabolites in PAH. Objectives: To characterize the gut microbiome and microbial metabolites in patients with PAH. Methods: We performed 16S ribosomal RNA gene and shotgun metagenomics sequencing on stool from patients with PAH, family control subjects, and healthy control subjects. We measured markers of inflammation, gut permeability, and microbial metabolites in plasma from patients with PAH, family control subjects, and healthy control subjects. Measurements and Main Results: The gut microbiome was less diverse in patients with PAH. Shannon diversity index correlated with measures of pulmonary vascular disease but not with right ventricular function. Patients with PAH had a distinct gut microbial signature at the phylogenetic level, with fewer copies of gut microbial genes that produce antiinflammatory short-chain fatty acids (SCFAs) and secondary bile acids and lower relative abundances of species encoding these genes. Consistent with the gut microbial changes, patients with PAH had relatively lower plasma concentrations of SCFAs and secondary bile acids. Patients with PAH also had enrichment of species with the microbial genes that encoded the proinflammatory microbial metabolite trimethylamine. The changes in the gut microbiome and circulating microbial metabolites between patients with PAH and family control subjects were not as substantial as the differences between patients with PAH and healthy control subjects. Conclusions: Patients with PAH have proinflammatory gut dysbiosis, in which lower circulating SCFAs and secondary bile acids may facilitate pulmonary vascular disease. These findings support investigating modulation of the gut microbiome as a potential treatment for PAH.

Is Ireland ready for tobacco endgame? A national survey of knowledge and attitudes to tobacco endgame

Background

In 2013 ‘Tobacco-Free Ireland’ (TFI) shifted Irish national policy from tobacco control to “tobacco endgame”: policies, plans and interventions seeking to end the tobacco epidemic completely. Recent trends suggest the current 2025 TFI goal will not be achieved. This cross-sectional study is a timely assessment of public knowledge and attitude to re-focus Irish “tobacco endgame” planning.

Methods

A literature-informed, pre-tested survey instrument was telephone-administered to a representative sample of 1000 members of the Irish public aged ≥15 years recruited via random digit dialling in February 2022. Prevalence of “tobacco endgame” views was measured; logistic regression determined factors associated with key responses.

Results

Response rate was 30% (n = 1,000, post-hoc weighting applied). While TFI goal awareness was low (34%), support was high (75%), albeit most (61%) recognised postponement beyond 2025 was required for achievability. There was majority support for 18/22 endgame measures assessed. Product-focused tactics were popular, while views on targeting users were mixed: e.g. 86% supported a reduction in tobacco-product nicotine content; 40% supported introduction of a tobacco-user license. Phasing-out tobacco sales was highly-supported (83%); however, this was contingent on special supports for those currently addicted. Support for the TFI goal was higher among non-tobacco users (aOR 2.66, 95%CI 1.89-3.76), females (aOR 1.57, 95%CI 1.17-2.11) and those of higher social class (aOR 1.72, 95%CI 1.25-2.35).

Conclusions

While achievement by 2025 is increasingly unrealistic, findings strongly affirm Irish public opinion is ready for “tobacco endgame”. Recognition of the needs of currently addicted tobacco users and focusing on subgroups with lower support levels should be integral to equitable “tobacco endgame” planning and communication. This study should mobilise renewed Irish political commitment to bold actions aimed at ending smoking-related harm.

Key messages

• There is strong support for tobacco endgame measures among the Irish population, which is a supportive factor for bold political leadership to make these radical ideas a reality.

• Public preference for product and non-user-focused measures aligns with tobacco endgame discourse and should aid policy reframing to tackle structures and dynamics sustaining the tobacco epidemic.

Fresh street: the development and feasibility of a place-based, subsidy for fresh fruit and vegetables

Background

Many UK communities experience food insecurity, and consume diets high in energy-dense, nutrient poor, processed foods and low in fruit and vegetables (FV). We explored a novel area-based approach to promote FV consumption and healthy eating in one such community.

Methods

We developed a weekly subsidy scheme for fresh FV with key local stakeholders in an area of socioeconomic deprivation in Northern England. The scheme (Fresh Street) offered five £1 vouchers to every household, regardless of income or household type. Vouchers were redeemable with local suppliers of fresh FV (not supermarkets). The feasibility of the scheme was assessed in four streets using rapid ethnographic assessment and voucher redemption information.

Results

Local councillors and public health teams were supportive of the scheme. Most eligible households joined the scheme (n = 80/97, 83%), and 89.3% (17 849/19 982) of vouchers issued were redeemed. Householders reported that the scheme made them think about what they were eating, and prompted them to buy and eat more FV.

Conclusions

This feasibility study reported high levels of acceptance for a place-based, household-level weekly FV subsidy scheme. Further research is required to evaluate the effectiveness of this approach to creating healthy diets, eating behaviours and food systems.

PARE0007 PATIENT AND PUBLIC INVOLVEMENT IN CLINICAL TRIAL DESIGN

Background:

Patient and public involvement (PPI) is gaining increasing recognition as important in ensuring research is relevant and acceptable to participants. Rheuma Tolerance for Cure (RTCure) is a 5 year international collaboration between academia and industry; focusing on earlier detection and prevention of rheumatoid arthritis (RA) through the use of immune-tolerising treatments.

Objectives:

To bring lived experience and insight into scientific discussions; and to evolve collaboration between lay representatives and academia/industry.

Methods:

9 Patient Research Partners (PRPs) from 5 European countries were recruited via the EULAR PARE Network and institutions within the RTCure Consortium (8 PRPs with RA and 1 ‘at risk’). They were asked to enter into a legal agreement with the Consortium. PRPs participated in teleconferences (TCs) and were invited to attend face-to-face (F2F) meetings at least annually. Requests for input/feedback were sent from researchers to PRPs via the project’s Patient Engagement Expert [SK].

Results:

PRP involvement has given researchers and industry partners a new perspective on patient priorities, and focused thought on the ethics of recruitment for and participation in clinical trials of people ‘at risk’ of developing RA. PRPs have helped define the target populations, given their thoughts on what types of treatments are acceptable to people ‘at risk’ and have aided the development of a survey (sent to EULAR PARE members) regarding the use of animal models in biomedical research. Positive informal feedback has been received from researchers and industry regarding the contribution of PRPs to the ongoing project (formal evaluation of PPI in RTCure will be carried out in 2020 and at the project end in 2022).

Challenges:

Legal agreements- Many PRPs refused to sign the Consortium’s complex PRP Agreement; feeling it unnecessary, incomprehensible and inequitable. After extensive consultation with various parties (including EULAR and the Innovative Medicines Initiative) no similar contract was found. Views for its requirement even varied between legal experts. After 2 years of intense discussion, a simple non-disclosure agreement was agreed upon. Ideally any contract, if required, should be approved prior to project onset.

Meeting logistics- Other improvements identified were to locate the meeting venue and accommodation on the same site to minimise travel, and to make it easier for PRPs to take breaks when required. This also facilitates informal discussions and patient inclusivity. We now have agreed a policy to fund PRPs extra nights before and after meetings, and to bring a carer if needed.

Enabling understanding– Future annual meetings will start with a F2F meeting between PRPs and Work Package Leads. Researchers will be encouraged to start presentations with a summary slide in lay language. Additionally, an RTCure Glossary is in development.

Enabling participation– SK will provide monthly project updates and PRP TCs will be held in the evening (as some PRPs remain employed). PRPs will be invited to all project TCs and F2F meetings. Recruitment is underway to increase the number of ‘at risk’ PRPs as their viewpoint is vital to this study.

Conclusion:

Currently PPI in RTCure is an ongoing mutual learning process. Universal guidance regarding what types of contracts are needed for PPI would be useful. Communication, trust and fruitful discussions have evolved through F2F meetings (both formal and informal) between PRPs, academia and industry. It is important that all parties can be open with each other in order to make PPI more meaningful.

Acknowledgments:

This work has received support from the EU/EFPIA Innovative Medicines Initiative 2 Joint Undertaking RTCure grant number 777357.

Disclosure of Interests:

Savia de Souza: None declared, Ruth Williams: None declared, Eva Johansson: None declared, Codruta Zabalan: None declared, Tom Esterine: None declared, Margôt Bakkers: None declared, Wolfgang Roth: None declared, Neil Mc Carthy: None declared, Meryll Blake: None declared, Susanne Karlfeldt: None declared, Martina Johannesson: None declared, Karim Raza Grant/research support from: KR has received research funding from AbbVie and Pfizer, Consultant of: KR has received honoraria and/or consultancy fees from AbbVie, Sanofi, Lilly, Bristol-Myers Squibb, UCB, Pfizer, Janssen and Roche Chugai, Speakers bureau: KR has received honoraria and/or consultancy fees from AbbVie, Sanofi, Lilly, Bristol-Myers Squibb, UCB, Pfizer, Janssen and Roche Chugai

Salivary C-reactive protein among at-risk adolescents: A methods investigation of out of range immunoassay data

Inflammatory markers including C-Reactive Protein (CRP) are increasingly used within research and clinical settings. Yet, varying methodologies for cleaning immunoassay data with out of range (OOR) samples may alter characteristic levels of CRP, thereby obscuring interpretation and reliability. This study investigated the influence of eight immunoassay OOR data treatment techniques on salivary CRP (sCRP) samples from at-risk adolescents. Participants from the 'Sleep and Education: learning New Skills Early' (SENSE) Study were 86 adolescents at-risk for depression (50 female), aged 14.29 years (SD = 1.04). ANOVA results showed no statistically significant differences in average morning (F(7, 590) = 1.24, p = .28) and evening (F(7, 599)=1.29, p = .25) values produced by each OOR data cleaning technique. However, varying techniques produced differences in the magnitude of Pearson's correlations between consecutive saliva samples (r's between 0.27-0.78), and influenced the significance of a sCRP diurnal pattern; two techniques produced statistically higher morning than evening sCRP levels (t(85) = 2.70, p = .01 and t(85) = 2.67, p = .01), whereas six techniques failed to find statistical differences between morning and evening sCRP levels (p's >.05). Varying techniques also produced statistically divergent associations between sCRP and age and depressive symptoms. Results from this study provide evidence for the temporal stability of sCRP among adolescents, show winsorization as an effective OOR data management technique, and highlight the influence of methodological decisions in cleaning salivary biomarker data and the need for consistency within the field.

Inequalities in oral health: the role of sociology

This paper seeks to identify an important point of contact between the literature on inequalities in oral health and the sociology of power. The paper begins by exploring the problem of social inequalities in oral health from the point of view of human freedom. It then goes on to briefly consider why inequalities in oral health matter before providing a brief overview of current approaches to reducing inequalities in oral health. After this the paper briefly introduces the problem of power in sociology before going on to outline why the problem of power matters in the problem of inequalities in oral health. Here the paper discusses how two key principles associated with the social bond have become central to how we think about health related inequalities. These principles are the principle of treating everyone the same (the principle of autonomy) and the related principle of allowing everyone to pursue their own goals (the principle of intimacy). These principles are outlined and subsequently discussed in detail with application to debates about interventions to reduce oral health related inequalities including that of water fluoridation. The paper highlights how the 'Childsmile' programme in Scotland appears to successfully negotiate the tensions inherent in attempting to do something about inequalities in oral health. It then concludes by highlighting some of the tensions that remain in attempting to alleviate oral health related inequalities.

The association between emotions and eating behaviour in an obese population with binge eating disorder

There is utility in understanding the antecedents of binge eating (BE), with a view to explaining poorer weight loss treatment responses in this subgroup. A systematic review was completed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines with the aim of exploring associations between emotions and eating behaviour in a population affected by obesity and binge eating disorder (BED). A comprehensive literature search of four electronic databases (2004-2014) yielded 15 studies for inclusion. Included studies performed poorly on data quality analysis with respect to controlling for confounding variables, and sample size. Included papers largely focused on negative emotions as antecedents of BE; depression was consistently associated with a BED-obese classification and BE. Negative mood, sadness, tension and instability of emotions were found to be antecedents of BE in an adult BED-obese sample. However, findings were mixed regarding the role of stress, anger and positive emotions within the BED-obese population. Recommendations are presented for the identification of BED, and ecologically valid experimental designs that further understanding of the complex and varied emotions that associate with BE. The implications of these and other limitations for both researchers and practitioners are discussed. The paper concludes with recommendations for future research alongside suggestions for practitioners. © 2015 World Obesity.

Veterinarian challenges to providing a multi-agency response to farm animal welfare problems in Ireland: responding to the human factor

In 2012, the authors undertook a study of the challenges facing government and private veterinarians in responding to the human element of farm animal welfare incidents (i.e. the personal problems and difficulties of farmers that can result in farm animal neglect). This paper reports their findings and examines the role of veterinarians in responding to the difficulties of farmers. It also looks at their experiences of attempting to build a multi-agency approach involving veterinary and human support services. This paper builds on a study whereby the authors considered how social, health and attitudinal factors, as well as mental health problems, contribute to farm animal welfare incidents in Ireland. An early warning system involving relevant agencies is in place to identify and prevent farm animal welfare problems before they become critical. The literature provides examples of private veterinarians combining with support services where there are indicators of animal and human abuse. Yet there are no research examples of government or private veterinarians linking with support services to resolve farm animal welfare cases where there are social, health, and/or mental health difficulties with the herd owner. Four focus groups were conducted with government veterinarians (n = 18) and three with private veterinarians (n = 12). Government veterinarians made contact with support services to seek advice on how best to respond to the human element of farm animal welfare incidents, and/or to seek support for the herd owner. Contact between government and private veterinarians was driven by the former. Communication between agencies was influenced by individual efforts and personal contacts. Formal structures and guidelines, perceived professional capabilities in determining herd owner needs, and client confidentiality concerns among support services and private veterinarians were less influential. The fear of losing clients and the financial implications of this were also cited by private veterinarians. Family, neighbours and local support groups assisted in reaching an on-farm solution. The paper concludes with the requirements for a multi-agency approach in Ireland: the provision of tailored information and guidelines targeting government and private veterinarians and support services, and a comprehensive structure for relationship-building, planning, and cross-reporting between all the relevant agencies.

Dilemmas experienced by government veterinarians when responding professionally to farm animal welfare incidents in Ireland

OBJECTIVES

This paper identifies the dilemmas experienced by government veterinarians during their investigations of farm animal welfare incidents that involve herd owner social, health, and/or psychological difficulties. The paper builds on exploratory qualitative research into the impact of these difficulties on farm animal welfare.

DESIGN

The study used a qualitative research approach. Focus groups were conducted.

SETTING

In Ireland, an Early Warning System (EWS), which brings together relevant agencies, is in place to identify and prevent farm animal welfare problems before they become critical. This study is concerned with the experiences of government veterinarians who respond to farm animal welfare incidents. Specific focus is on incidents that involve herd owner social/psychological/health-related difficulties.

PARTICIPANTS

In total, n=18 government veterinarians (representing 15 per cent of the population sample), all with a keen interest in farm animal welfare, participated. These were selected on the basis of their interest, experience, and involvement in farm animal welfare. One government veterinarian declined to participate. Four focus groups were conducted with government veterinarians. These took place in the south (S), south-west (SW), midlands (M), and north-west region of Ireland (NW). All 16 District Veterinary Offices (DVOs) were represented in the focus groups.

RESULTS

The results reveal three professional dilemmas that exist for government veterinarians: (1) defining professional parameters; (2) determining the appropriate response; (3) involvement versus detachment. Participants reported not wanting any additional training. Instead, it was agreed that a formal bridge to social service providers who have the professional capability to respond appropriately and with confidence, was required.

CONCLUSIONS

Clearly defined guidelines are required for government veterinarians in their encounters with farm animal welfare incidents where there is a complex human component. A coordinated multiagency approach that is flexible enough to meet the needs of individual farm animal welfare cases is required.

Longer-term risk of Mycobacterium bovis in Irish cattle following an inconclusive diagnosis to the single intradermal comparative tuberculin test

In Ireland, new bovine tuberculosis (bTB) cases are detected using both field and abattoir surveillance. During field surveillance, an animal may be deemed a 'standard inconclusive reactor' (SIR) to the single intradermal comparative tuberculin test (SICTT) if the bovine response is >2mm, and from 1 to 4mm greater than the avian response. Little is known about the future infection risk posed by SIR animals that pass a subsequent retest, so-called 'transient SIR' (TIR) animals. The objective of this study was to critically evaluate the future bTB status of TIR animals, by examining the future risk of bTB diagnosis over the 4 years following initial SIR diagnosis and clearance at the subsequent retest. The study included all TIRs that were identified as SIRs in 2005 in otherwise free herds at tests with no other reactors at that test and that were clear at the subsequent retest. The analysis was restricted to cows that were neither sold, other than direct to slaughter, nor exported from the herd during the follow up period (to the end of 2009). Five control cows were randomly selected from each study herd. A parametric survival model with shared frailties, to account for clustering within herds, was developed to model time from passing a retest to future bTB diagnosis. The final parametric survival model contained the variables: TIR status in 2005, inconclusive status during the follow-up period, location, herd restricted during the study, time since last restriction within the herd and age. The time ratio for the TIR status variable was significant (p<0.001) indicating that on average the time to diagnosis with bTB for TIRs was 78% shorter compared to the non-TIRs. The frailty term was significant (p<0.001) indicating that animals within some herds were more likely to become reactors compared to other herds. These results have important implications for national policy and future management of TIR animals. Further, private veterinary practitioners and their clients should be aware of the increased risk associated with TIRs.

An audit of the laboratory service provided to the Health Service Executive Orthodontic Department, St James Hospital, Dublin

PURPOSE OF THE STUDY

To evaluate the service purchased from contracted orthodontic laboratories used by HSE (SWA) regional orthodontic unit, St. James's Hospital, Dublin and identify deficiencies in the current service.

MATERIALS AND METHODS

A data collection questionnaire was designed and distributed to the departmental orthodontists for a period of three months (October-December 2004). Gold standards, drawn up based on the authors' ideal requirements and published guidelines, were supplied to grade the work returned.

RESULTS

During the study period 363 items of laboratory work were requested. 20% of the laboratory work arrived late and most of the delayed work was delayed for more than 24 hours. Most laboratory delays occurred with functional appliances, retainers and study models. Prior to fit, 20% of the appliances required adjustments for more than 30 seconds. 65% of laboratory work returned to the department met all of the gold standards. 10% of appliances were considered unsatisfactory. Functional appliances were most often ill fitting accounting for almost half of the unsatisfactory laboratory work.

CONCLUSIONS

The majority of the laboratory work returned to the department met our gold standards and arrived on time. Forty six percent of the appliances required adjustments. Functional appliances required the most adjustments; one in five of all functional appliances ordered were considered unsatisfactory.

111In-pentetreotide versus bone scintigraphy in the detection of bony metastases of neuroblastoma

Bone scintigraphy (BS) is widely utilized for the assessment of bone metastases (BMs) of neuroblastoma (NB). Since 111In-pentetreotide scintigraphy (PS) has been used to image NB with high sensitivity, we compared the sensitivity and specificity of PS with that of BS for the detection of BMs of NB. Nine patients with NB underwent both PS and BS for staging and/or restaging of their disease. The sensitivity and specificity of both imaging approaches were compared based on the findings of histopathology, other conventional imaging methods and subsequent clinical follow-up. In five of the nine patients, both PS and BS were negative for BMs. Radiographic bone surveys (RBSs) were also negative in these patients, except in one who showed a suspicious tibial lesion, but a computed tomography-guided biopsy failed to show evidence of disease. These patients remained without clinical evidence of BMs after a median duration of more than 15 months (range, 6-19 months). In three of four remaining patients, both PS and BS were positive for BMs, whilst only PS was positive in one patient. Overall, PS showed a greater number of BMs (30 vs. 7) with greater conspicuity compared with BS. The initial experience comparing BS with PS suggests that PS may provide a better assessment of the extent of BMs of NB, and that it may be useful as an adjunct to BS at institutions in which 131I- or 123I-metaiodobenzylguanidine is not available, particularly if BS is negative. In patients with similarly positive BS, PS might still provide unique prognostic information beyond that provided by BS. Further studies are therefore warranted.

Inhibition of p53 transcriptional activity by the S100B calcium-binding protein

The levels of S100 Ca(2+)-binding proteins correlate with the progression of certain tumors, but their role, if any, in carcinogenesis is still poorly understood. S100B protein associates with both the p53 oligomerization domain (residues 325-355) and the extreme C terminus of the tumor suppressor p53 (residues 367-392). Consequently, S100B inhibits p53 tetramer formation and p53 phosphorylation mediated by protein kinase C, on p53 C-terminal end. In this report, we show that the S100B protein decreases p53 DNA binding and transcriptional activity. The effect of S100B is reflected in vivo by a reduced accumulation of p53, p21, and MDM2 protein levels in co-transfection assays and in response to bleomycin. The S100B can still interact with p53 in the absence of p53 extreme C-terminal end and reduce the expression of p53 downstream effector genes. These data indicate that S100B does not require p53 extreme C-terminal end to inhibit p53 activity. Collectively, these findings imply that elevated levels of S100B in tumors such as astrocytomas and gliomas could inhibit p53 functions and contribute to cancer progression.

Predictors of prostate carcinoma: accuracy of gray-scale and color Doppler US and serum markers

PURPOSE

To determine the accuracy of detecting prostate cancer by using (a) gray-scale and color Doppler transrectal ultrasonography (US), (b) serum and excess prostate-specific antigen (PSA) levels, and (c) targeted and sextant transrectal US-guided biopsy. The relationship between US-detected neovascularity and tumor biologic activity was also evaluated.

MATERIALS AND METHODS

Between 1995 and 1999, 544 patients with elevated PSA levels and/or abnormal digital rectal examination underwent transrectal US-guided sextant biopsy and targeted biopsy of US abnormalities. Sensitivity, specificity, and accuracy of gray-scale US, color Doppler US, targeted biopsy, and PSA and excess PSA were calculated.

RESULTS

Gray-scale US depicted 78 (41.1%) of 190 cancers, whereas color Doppler US depicted 30 (15.8%) additional cancers. Targeted biopsy was used to detect 108 (56.8%) cancers, whereas sextant biopsy was used to detect 82 (43.2%) additional cancers. Although US-visible cancers had a higher Gleason grade than did cancers discovered at sextant biopsy (P <.05), 25 of the 66 cancers identified with sextant biopsy alone were Gleason grade 6 or higher. Color Doppler US-depicted hypervascularity correlated with biologically aggressive tumors. Excess PSA was normal in 58 (30.5%) cancers, with an accuracy of 67.3%, resulting in better prediction of prostate tumors than with serum PSA level alone.

CONCLUSION

Gray-scale transrectal US, even coupled with color Doppler US, is inadequate for prostate carcinoma screening; therefore, targeted biopsy should always be accompanied by complete sextant biopsy sampling.

Effect of lung inflation on arterial spin labeling signal in MR perfusion imaging of human lung

The effect of lung inflation on arterial spin-labeling signal in lung perfusion is investigated. Arterial spin-labeling schemes, called alternation of selective inversion pulse (ASI) and its hybrid (HASI), which uses blood water as an endogenous, freely diffusible tracer, were applied to magnetic resonance (MR) perfusion imaging of the lung. Perfusion-weighted images of the lung from nine healthy volunteers were obtained at different time delays. There was a significant signal difference in ASI images acquired at different respiratory phases. Greater signal enhancement has been observed when the volunteers performed breath holding on end expiration than on end inspiration. This is in agreement with the normal physiologic effect of lung inflation on the pressure-flow relationship of pulmonary vasculature. ASI and HASI perfusion-weighted images show similar lung features and image quality. Preliminary results from pulmonary embolism patients indicate that arterial spin labeling is sensitive for the detection of areas of perfusion deficit. J. Magn. Reson. Imaging 2001;13:954-959.

An update on orthodontic manpower in ireland

There has been considerable debate in Europe over the past few years on manpower requirements in orthodontics. In some countries today the need for orthodontic care cannot be accommodated due to lack of professional manpower whereas in others a surplus of orthodontic treatment facilities exists. The aim of the present study was to establish a baseline for orthodontic demographics in the Republic of Ireland. The number of orthodontists currently practising in Ireland was identified together with the number of Irish graduates currently on training programmes. Population figures were obtained from the Central Statistics Office. The orthodontic manpower situation has altered dramatically in the Republic of Ireland over the past 20 years. The number of 12-year-olds per orthodontist has reduced over the past 18 years from 2773 in 1980 to 890 in 1998. The age profile of the orthodontists presently practising in Ireland is low with an expected retirement over the next 20 years of only 28 of the 69 orthodontists identified. This study provides baseline information on orthodontic manpower in Ireland, and will facilitate Ireland's participation in similar or comparative studies in the future.

MR imaging of bone oedema: mechanisms and interpretation

Widespread use of MRI now allows the routine identification of previously unevaluated traumatic bone marrow oedema and haemorrhage. Similar marrow oedema is identified in patients with tumours, hyperaemia and medullary congestion. Patterns and extent of traumatic bone marrow oedema and haemorrhage are dictated by mechanism. Diffusion techniques may allow precise evaluation of severity of injury. Illustrative examples and discussion are presented. Eustace, S. (2001). Clinical Radiology56, 4-12.

National survey of internal medicine residency programs of their 1st-year experience with the electronic residency application service and national resident match program changes

BACKGROUND

The residency recruitment and selection process is a critical one for residency programs and medical students. In 1999, internal medicine programs conducted the residency match on the Web for the first time using the Electronic Residency Application Service (ERAS).

PURPOSE

The authors wished to study the impact of this change on house staff recruitment and quality of match.

METHOD

A Web-based survey with e-mail, paper, and fax reminders was sent to all 407 internal medicine residency programs after the 1999 match.

RESULTS

Eighty-six percent of reporting programs found the screening of applicants easier. The overall number of applicants varied greatly (48% of programs reported more applicants; 32% reported fewer). The quality of final match was rated the same as previous years by 47%, better by 38%, and worse by 15%.

CONCLUSIONS

The transition to ERAS was successful in internal medicine. However, there are several areas that were identified that will improve the ERAS process as it evolves.

Multidisciplinary case-based learning for undergraduate students

This report describes the introduction of case-based learning into the final-year dental programme at the Dublin Dental School. Students attended a series of one-hour sessions in groups of 8. Each group appointed a chairman for each session and a tutor facilitated the discussion. Case details were provided during the session with relevant diagnostic records. At weekly discussion sessions, the group findings and treatment options were considered. The diagnosis and treatment plans were then discussed by clinicians involved in the treatment of the case. Following the last session, the case-based learning programme was evaluated by means of a questionnaire distributed to both tutors and students. Both students and tutors rated the sessions positively. Case-based learning was found to be a worthwhile progression from problem-based learning.

Analysis of diffusion changes in posttraumatic bone marrow using navigator-corrected diffusion gradients

OBJECTIVE

This study was undertaken to analyze diffusion characteristics of normal and posttraumatic bone marrow.

MATERIALS AND METHODS

Fifty consecutive patients with knee pain underwent both conventional and diffusion-weighted MR imaging (b values, 0-980 sec/mm2). Diffusion maps derived from source data were analyzed on a workstation using region-of-interest techniques. Apparent diffusion values recorded in normal marrow were compared with values recorded in abnormal posttraumatic bone marrow (square centimeters per second).

RESULTS

Normal bone marrow identified in 35 patients showed minimal diffusion, with a mean value of 0.15x10(-5) cm2/sec. Bone marrow in 15 patients sustaining direct traumatic injury (21 bone bruises) showed markedly increased diffusion, with a mean value of 0.8x10(-5) cm2/sec (range, 0.4-1.3 cm2/sec).

CONCLUSION

Marrow injury after trauma with trabecular damage allows increased movement or diffusion of interstitial water relative to normal marrow. The magnitude of diffusion change appears to reflect the severity of marrow injury.

Sperm deposition site during ICSI affects fertilization and development

OBJECTIVE

To evaluate the effects of sperm placement during ICSI relative to the M-II spindle location on fertilization and preimplantation development.

DESIGN

Retrospective analysis of oocyte fertilization and embryo development with respect to sperm deposition site during ICSI.

SETTING

A program of IVF-ET.

PATIENT(S)

Seven hundred seventy-six patients.

INTERVENTION(S)

Egg quality, sperm deposition site, and polar-body position were recorded during ICSI; fertilization was assessed on day 1; embryo development was evaluated on days 2 and 3.

MAIN OUTCOME MEASURE(S)

Fertilization, embryo development, and implantation rates.

RESULT(S)

Normal fertilization is not affected by polar-body orientation, with the exception of a significantly lower fertilization rate from a 9 o'clock polar-body orientation. Injections with the polar-body positioned at 7 or 11 o'clock result in the greatest number of high-quality embryos, significantly more than the adjacent 6 or 12 o'clock polar-body orientations and irrespective of oocyte anomaly frequency. Embryos originating from the 7 or 11 o'clock polar-body category implant at a higher rate, although the data are not significant.

CONCLUSION(S)

The placement of the sperm during ICSI relative to the presumed location of the meiotic spindle significantly impacts fertilization and high-quality embryo development. Sperm deposition in the M-II spindle area should be avoided. It appears that development, and not fertilization, is improved by decreasing the distance between the sperm cell and the spindle.

Transient osteoporosis of hip in pregnancy

Transient osteoporosis in pregnancy is a relatively rare disorder characterized by disabling pain in the hip without prior trauma and by striking radiographic evidence of osteopenia that is limited to the hip. Clinical and radiographic findings regress spontaneously within months after pregnancy and without late sequelae. In this study, we report on a case of a 28-yr-old Caucasian woman who suffered from transient osteoporosis during pregnancy. Nine months later, the patient was asymptomatic and there was resolution of the bone marrow edema pattern seen on the initial magnetic resonance imaging scan of her hip. Follow-up bone densitometry at 1 yr revealed a dramatic increase (12.3%) in bone mineral density of the symptomatic hip. We review the literature and discuss possible mechanisms involved in the pathogenesis of transient osteoporosis in pregnancy.

Supernumerary teeth--an overview of classification, diagnosis and management

Most supernumerary teeth are located in the anterior maxillary region. They are classified according to their form and location. Their presence may give rise to a variety of clinical problems. Detection of supernumerary teeth is best achieved by thorough clinical and radiographic examination. Their management should form part of a comprehensive treatment plan. This article presents an overview of the clinical problems associated with supernumerary teeth and includes a discussion of the classification, diagnosis and management of this difficult clinical entity.

Whole-body MR imaging. Practical issues, clinical applications, and future directions

Whole-body MR imaging is in evolution, and although accepting and recognizing limitations, it is likely that both technique and incurred acquisition times will shorten over the next decade. Although the development of dedicated whole-body MR scanners appears to offer the greatest promise for the future, the development of moving table tops, optimized pulse sequences, and advances in gradient technology now facilitate practical whole-body MR imaging using existing clinical systems.

Cleidocranial dysplasia: radiological appearances on dental panoramic radiography

OBJECTIVE

To report the effectiveness of dental panoramic radiography in identifying features pathognomonic for cleidocranial dysplasia.

METHODS

Panoramic radiographs of nine male Caucasian patients with cleidocranial dysplasia are analysed.

RESULTS

In addition to the established dental complications of failure of eruption of the permanent dentition and multiple supernumerary teeth, morphological abnormalities of the maxilla and mandible, particularly in the ascending ramus and coronoid process were present.

CONCLUSION

Dental panoramic radiography is a valuable adjunct in confirming the diagnosis of cleidocranial dysplasia.

Gadd45, a p53-responsive stress protein, modifies DNA accessibility on damaged chromatin

This report demonstrates that Gadd45, a p53-responsive stress protein, can facilitate topoisomerase relaxing and cleavage activity in the presence of core histones. A correlation between reduced expression of Gadd45 and increased resistance to topoisomerase I and topoisomerase II inhibitors in a variety of human cell lines was also found. Gadd45 could potentially mediate this effect by destabilizing histone-DNA interactions since it was found to interact directly with the four core histones. To evaluate this possibility, we investigated the effect of Gadd45 on preassembled mononucleosomes. Our data indicate that Gadd45 directly associates with mononucleosomes that have been altered by histone acetylation or UV radiation. This interaction resulted in increased DNase I accessibility on hyperacetylated mononucleosomes and substantial reduction of T4 endonuclease V accessibility to cyclobutane pyrimidine dimers on UV-irradiated mononucleosomes but not on naked DNA. Both histone acetylation and UV radiation are thought to destabilize the nucleosomal structure. Hence, these results imply that Gadd45 can recognize an altered chromatin state and modulate DNA accessibility to cellular proteins.