Multipath artifacts enable angular contrast in multimodal endoscopic optical coherence tomography

Multipath artifacts are inherent to double-clad fiber based optical coherence tomography (OCT), appearing as ghost images blurred in the A-line direction. They result from the excitation of higher-order inner-cladding modes in the OCT sample arm which cross-couple into the fundamental mode at discontinuities and thus are detected in single-mode fiber-based interferometers. Historically, multipath artifacts have been regarded as a drawback in single fiber endoscopic multimodal OCT systems as they degrade OCT quality. In this work, we reveal that multipath artifacts can be projected into high-quality two-dimensional en face images which encode high angle backscattering features. Using a combination of experiment and simulation, we characterize the coupling of Mie-range scatterers into the fundamental image (LP01 mode) and higher-order image (multipath artifact). This is validated experimentally through imaging of microspheres with an endoscopic multimodal OCT system. The angular dependence of the fundamental image and higher order image generated by the multipath artifact lays the basis for multipath contrast, a ratiometric measurement of differential coupling which provides information regarding the angular diversity of a sample. Multipath contrast images can be generated from OCT data where multipath artifacts are present, meaning that a wealth of clinical data can be retrospectively examined.

Association of Prostate Specific Antigen Kinetics after Testosterone Recovery with Subsequent Recurrence: Secondary Analysis of a Phase III Randomized Controlled Trial

PURPOSE/OBJECTIVE(S)

The combination of short-term androgen deprivation therapy (ST-ADT) with prostate radiotherapy (RT) is a standard of care for patients with localized prostate cancer (LPCa). After cessation of ST-ADT, it takes about 8 to 10 months for the testosterone (T) to recover to supracastrate levels, which could drive changes in PSA kinetics. It largely remains unknown whether early changes in PSA kinetics after T recovery could predict for subsequent biochemical relapse.

MATERIALS/METHODS

We performed a secondary analysis of a phase III randomized controlled trial in which patients with newly diagnosed LPCa with Gleason score £7, clinical stage T1b to T3a, and PSA <30 ng/mL were randomly allocated to neoadjuvant and concurrent ADT for 6 months starting 4 months before prostate RT (76 Gy in 38 fractions over 7.5 weeks) or concurrent and adjuvant ADT for 6 months starting simultaneously with prostate RT. Clinical assessment and laboratory investigations were repeated 1 month after completion of ADT, every 4 months for the first 2 years, every 6 months for the next 3 years, and annually thereafter. We calculated the PSA doubling time (PSADT) based on PSA values up to 18 months after recovery of T to a supracastrate level (>50 ng/dL). Patients with ³3 PSA measurements after T recovery to supracastrate level were included in this analysis. Fine and Gray cumulative incidence of biochemical recurrence (BCR) was calculated in patients with PSADT at or above median versus below median. Deaths were considered as competing events. All endpoints were calculated from the time of T recovery to supracastrate level. Subdistribution hazard ratios (sHR) with 95% confidence intervals (CI) were estimated for association of PSADT with relative incidence of recurrence using competing risk regression after adjusting for tumor stage, pre-treatment PSA, Gleason score, treatment regimen, and age at randomization.

RESULTS

Overall, 311 patients were eligible for this analysis. Median PSADT was 8 months. Cumulative incidence of BCR at 10 years was 31.0% and 20.7% in patients with PSADT <8 months and ³8 months, respectively. Longer PSADT was associated with a significantly lower risk of cumulative incidence of BCR (sHR for PSADT as a continuous variable 0.43, 95% CI: 0.28-0.66; sHR for PSADT ³8 months 0.54, 95% CI: 0.30-0.99). After adjustment for time to recovery of T to supracastrate level in addition to the aforementioned variables, longer PSADT (³8 months) was associated with lower risk of cumulative incidence of BCR (sHR: 0.53, 95% CI: 0.27-1.01).

CONCLUSION

These findings suggest that early PSA kinetics within 18 months of recovery of T to a supracastrate level predict for subsequent biochemical failure. Taking account of early changes in PSA after testosterone recovery may allow for recognition of potential failures earlier in the disease course and thereby permit greater personalization of management decisions.

Triple-clad W-type fiber mitigates multipath artifacts in multimodal optical coherence tomography

Multimodal endoscopic optical coherence tomography (OCT) can be implemented with double-clad fiber by using the presumed single-mode core for OCT and the higher numerical aperture cladding for a secondary modality. However, the quality of OCT in double-clad fiber (DCF) based systems is compromised by the introduction of multipath artifacts that are nt present in single-mode fiber OCT systems. Herein, the mechanisms for multipath artifacts in DCF are linked to its modal contents using a commercial software package and experimental measurement. A triple-clad W-type fiber is proposed as a method for achieving multimodal imaging with single-mode quality OCT in an endoscopic system. Simulations of the modal contents of a W-type fiber are compared to DCF and single-mode fiber. Finally, a W-Type fiber rotary catheter is used in a DCF-based endoscopic OCT and autofluorescence imaging (AFI) system to demonstrate multipath artifact free OCT and AFI of a human fingertip.

Ethical aspects in the use of radiation in medicine: update from ICRP Task Group 109

Whereas scientific evidence is the basis for recommendations and guidance on radiological protection, professional ethics is critically important and should always guide professional behaviour. The International Commission on Radiological Protection (ICRP) established Task Group 109 to advise medical professionals, patients, families, carers, the public, and authorities about the ethical aspects of radiological protection of patients in the diagnostic and therapeutic use of radiation in medicine. Occupational exposures and research-related exposures are not within the scope of this task group. Task Group 109 will produce a report that will be available to the different interested parties for consultation before publication. Presently, the report is at the stage of a working document that has benefitted from an international workshop organised on the topic by the World Health Organization. It presents the history of ethics in medicine in ICRP, and explains why this subject is important, and the benefits it can bring to the standard biomedical ethics. As risk is an essential part in decision-making and communication, a summary is included on what is known about the dose-effect relationship, with emphasis on the associated uncertainties. Once this theoretical framework has been presented, the report becomes resolutely more practical. First, it proposes an evaluation method to analyse specific situations from an ethical point of view. This method allows stakeholders to review a set of six ethical values and provides hints on how they could be balanced. Next, various situations (e.g. pregnancy, elderly, paediatric, end of life) are considered in two steps: first within a realistic, ethically challenging scenario on which the evaluation method is applied; and second within a more general context. Scenarios are presented and discussed with attention to specific patient circumstances, and on how and which reflections on ethical values can be of help in the decision-making process. Finally, two important related aspects are considered: how should we communicate with patients, family, and other stakeholders; and how should we incorporate ethics into the education and training of medical professionals?

Oxidative Stress and Cardiovascular Risk in Type 1 Diabetes Mellitus: Insights From the DCCT/EDIC Study

Background

Hyperglycemia leading to increased oxidative stress is implicated in the increased risk for the development of macrovascular and microvascular complications in patients with type 1 diabetes mellitus.

Methods and Results

A random subcohort of 349 participants was selected from the DCCT / EDIC (Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications) cohort. This included 320 controls and 29 cardiovascular disease cases that were augmented with 98 additional known cases to yield a case cohort of 447 participants (320 controls, 127 cases). Biosamples from DCCT baseline, year 1, and closeout of DCCT , and 1 to 2 years post‐ DCCT ( EDIC years 1 and 2) were measured for markers of oxidative stress, including plasma myeloperoxidase, paraoxonase activity, urinary F 2α isoprostanes, and its metabolite, 2,3 dinor‐8 iso prostaglandin F 2α . Following adjustment for glycated hemoblobin and weighting the observations inversely proportional to the sampling selection probabilities, higher paraoxonase activity, reflective of antioxidant activity, and 2,3 dinor‐8 iso prostaglandin F 2α , an oxidative marker, were significantly associated with lower risk of cardiovascular disease (−4.5% risk for 10% higher paraoxonase, P <0.003; −5.3% risk for 10% higher 2,3 dinor‐8 iso prostaglandin F 2α , P =0.0092). In contrast, the oxidative markers myeloperoxidase and F 2α isoprostanes were not significantly associated with cardiovascular disease after adjustment for glycated hemoblobin. There were no significant differences between DCCT intensive and conventional treatment groups in the change in all biomarkers across time segments.

Conclusions

Heightened antioxidant activity (rather than diminished oxidative stress markers) is associated with lower cardiovascular disease risk in type 1 diabetes mellitus, but these biomarkers did not change over time with intensification of glycemic control.

Clinical Trial Registration

URL : https://www.clinicaltrials.gov . Unique identifiers: NCT 00360815 and NCT 00360893.

Communication disorders in a hospital elderly population

There is a paucity of information regarding the prevalence and causes of communication disorders in the elderly. Patients admitted to the acute ward of a department of medicine for the elderly were screened to ascertain the number of people presenting with communication disorders and to identify the underlying cause of the disorder. Patients were screened for deficits in speech, language, vision, hearing and cognition. The results indicate that 73% of the elderly population screened had speech and/or language problems, 11 % had visual deficits, 36% had hearing problems and 56% had a cognitive deficit on admission to hospital. These results have implications for patient care and staff training.

Lessons from a Balint group scheme led by psychiatry trainees for year 3 bristol medical students on their medicine/surgery placements

Background

The UK General Medical Council highlights the centrality of effective communication, reflective practice and the doctor-patient relationship in medical practice. A decline in empathy has been documented as occurring within clinical and early postgraduate years, potentially affecting diagnostic processes and patient engagement. Access to Balint groups can enhance awareness of the patient beyond the medical model, but remains limited at many UK medical schools. This scheme offered Balint groups to Bristol medical students in their first clinical year, demonstrating that this method is relevant beyond psychiatry.

Methods

Initial focus groups with medical students indicated that many felt unable to discuss distressing aspects of clinical encounters. During 2013-2014, a Balint scheme run by psychiatry trainees was started for 150 students in their psychiatry placements. During 2014-15, the scheme was introduced to all third-year medical students on their medicine/surgery placement. Balint leaders have group supervision with a psychoanalytic psychotherapist. Evaluation of the scheme was based on pre-and post-group questionnaires and leaders’ process notes.

Results

Sixteen groups led by 12 trainees were run twice over the year to serve 246 medical students. Two example cases are discussed here. Students appreciated the chance to discuss complex encounters with patients in a supportive peer environment, and work through a range of emotionally challenging issues.

Conclusions

Novel aspects of this work include the implementation of Balint groups within medicine and surgery placements; the enrolment of psychiatry trainees as leaders with group supervision and leadership training workshops from the UK Balint Society; and the scale of the scheme.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Zur Wirkung von substituierten α-Liponsäuren auf die Lipoamidoxidoreduktase -Reaktion

The reactions of various recently synthesized analogous of α-lipoic acid (especially with fluoride as substituent) with lipoic acid dehydrogenase from pig heart muscle were investigated. The influence of structural change on the reactivity of the various compounds, when reacting with lipoic acid dehydrogenase are discussed.

Criteria and suspension levels in diagnostic radiology

The EC (European Council) Directive on radiation protection of patients requires that criteria for acceptability of equipment in diagnostic radiology, nuclear medicine and radiotherapy be established throughout the member states. This study reviews the background to this requirement and to its implementation in practice. It notes and considers parallel requirements in the EC medical devices directive and International Electrotechnical Commission standards that it is also important to consider and that both sets of requirements should ideally be harmonised due to the global nature of the equipment industry. The study further reviews the types of criteria that can be well applied for the above purposes, and defines qualitative criteria and suspension levels suitable for application. Both are defined and relationships with other acceptance processes are considered (including acceptance testing at the time of purchase, commissioning and the issue of second-hand equipment). Suspension levels are divided into four types, A, B, C and D, depending on the quality of evidence and consensus they are based on. Exceptional situations involving, for example, new or rapidly evolving technology are also considered. The publication and paper focuses on the role of the holder of the equipment and related staff, particularly the medical physics expert and the practitioner. Advice on how the criteria should be created and implemented is provided for these groups and how this might be coordinated with the supplier. Additional advice on the role of the regulator is provided.

Justification of diagnostic medical exposures: some practical issues. Report of an International Atomic Energy Agency Consultation

OBJECTIVES

The Radiation Protection of Patients Unit of the International Atomic Energy Agency (IAEA) is concerned about the effectiveness of justification of diagnostic medical exposures. Recent published work and the report of an initial IAEA consultation in the area gave grounds for such concerns. There is a significant level of inappropriate usage, and, in some cases, a poor level of awareness of dose and risk among some key groups involved. This article aims to address this.

METHODS

The IAEA convened a second group of experts in November 2008 to review practical and achievable actions that might lead to more effective justification.

RESULTS

This report summarises the matters that this group considered and the outcome of their deliberations. There is a need for improved communication, both within professions and between professionals on one hand, and between professionals and the patients/public on the other. Coupled with this, the issue of consent to imaging procedures was revisited. The need for good evidence-based referral guidelines or criteria of acceptability was emphasised, as was the need for their global adaptation and dissemination.

CONCLUSION

Clinical audit was regarded as a key tool in ensuring that justification becomes an effective, transparent and accountable part of normal radiological practice. In summary, justification would be facilitated by the "3 As": awareness, appropriateness and audit.

DURATION-2: efficacy and safety of switching from maximum daily sitagliptin or pioglitazone to once-weekly exenatide

AIMS

In the initial 26-week, double-blind, double-dummy assessment period of the DURATION-2 trial in patients with Type 2 diabetes on metformin, the once-weekly glucagon-like peptide 1 (GLP-1) receptor agonist exenatide once-weekly resulted in greater HbA(1c) improvement and weight reduction compared with maximum approved daily doses of sitagliptin or pioglitazone. This subsequent, 26-week, open-label, uncontrolled assessment period evaluated the safety and efficacy of (i) continued exenatide once-weekly treatment and (ii) switching from sitagliptin or pioglitazone to exenatide once-weekly.

METHODS

Randomised oral medications were discontinued and all patients received exenatide once-weekly. Of the 364 patients [original baseline HbA(1c) 8.5 ± 1.1% (70 mmol/mol), fasting plasma glucose 9.0 ± 2.5 mmol/l, weight 88 ± 20 kg) who continued into the open-label period, 319 patients (88%) completed 52 weeks.

RESULTS

Evaluable patients who received only exenatide once-weekly demonstrated significant 52-week improvements (least square mean ± se) in HbA(1c) (-1.6 ± 0.1%), fasting plasma glucose (-1.8 ± 0.3 mmol/l) and weight (-1.8 ± 0.5 kg). Evaluable patients who switched from sitagliptin to exenatide once-weekly demonstrated significant incremental improvements in HbA(1c) (-0.3 ± 0.1%), fasting plasma glucose (-0.7 ± 0.2 mmol/l) and weight (-1.1 ± 0.3 kg). Patients who switched from pioglitazone to exenatide once-weekly maintained HbA(1c) and fasting plasma glucose improvements (week 52: -1.6 ± 0.1%, -1.7 ± 0.3 mmol/l), with significant weight reduction (-3.0 ± 0.3 kg). Exenatide once-weekly was generally well tolerated and adverse events were predominantly mild or moderate in intensity. Nausea was the most frequent adverse event in this assessment period (intent-to-treat: exenatide once-weekly-only 5%; sitagliptin→exenatide once-weekly 11%; pioglitazone→exenatide once-weekly 10%). No major hypoglycaemia was observed.

CONCLUSIONS

Patients who switched to once-weekly exenatide from daily sitagliptin or pioglitazone had improved or sustained glycaemic control, with weight loss.

Haemophilus influenzae abscess: inclusion in the differential diagnosis of a large pelvic mass?

BACKGROUND

This report describes an unusual first case in which an abscess containing Haemophilus influenzae incorporates the entire uterine cavity without overt signs of infection.

CASE

A 39-year-old woman presented with right lower quadrant abdominal pain and a large abdominal pelvic mass. Evaluation with computed tomography and ultrasonography showed a 20- x 14- x 10-cm cystic mass arising from the uterus. Tumor markers were negative. The patient underwent a total abdominal hysterectomy. Intraoperative findings included a 20-cm intramyometrial uterine abscess, completely replacing the uterine cavity. The abscess was densely adhered to the sigmoid colon. The mass was ruptured during the surgical procedure when mobilizing it off the colon, and cultures were obtained. Microbiologic culture illustrated H. influenzae. Pathologic diagnosis confirmed an intramyometrial abscess, originating from the wall of the uterus occupying the entire uterine cavity, lined with granulation tissue, foamy macrophages, and chronic inflammation.

CONCLUSION

Intramyometrial abscesses can masquerade as degenerating fibroids and, even with microorganisms, can exist without overt signs or symptoms of an active infection.

Patient flow from critical care to renal services: a year-long survey in a critical care network

BACKGROUND

The NSF for Renal Services stresses the importance of collaboration between renal services and critical care networks in managing patients with acute renal failure in the most clinically appropriate setting. Anecdotal evidence in our region suggested that some patients were remaining on critical care inappropriately because of a lack of capacity for step-down care in local renal units.

AIM

To determine the number of extra days patients spend on critical care receiving single-organ renal support before transfer to a renal unit.

DESIGN

Prospective, multi-centre, service evaluation.

METHODS

Prospective data were collected over a one-year period by either daily telephone calls or bedside review. Follow-up data were retrieved from electronic and patient records.

RESULTS

Five hundred and forty-two patients received renal replacement therapy (RRT) in critical care. With 68 (12.5%) patients already receiving RRT for end-stage renal failure, this gave an incidence of new RRT on critical care of 234 per million population per year. The median duration of RRT on critical care was 4 days (range 1-30). One hundred and twenty-seven patients (23%) were discharged from critical care still requiring RRT. A period of single-organ renal support (median 2 days, range 1-8) was provided to 74 of these patients (58%) using 113 critical care bed days.

DISCUSSION

Over half of patients receiving RRT on discharge from critical care in our network received a short period of single-organ renal support before step-down. This may represent either delayed discharge from critical care or a potential opportunity for care in an alternative high-dependency facility.

The SENTINEL project

Health-care expenditure on radiological equipment in Europe is a growing fraction of the gross domestic product for all member states. This increase in expenditure has been driven by technical developments in equipment design, matched by the introduction of novel clinical practices, examinations and procedures. The radiation protection implications of these developments have to be assessed. The SENTINEL co-ordination action covered radiation protection, safety and related issues that arise from these technical and clinical developments. SENTINEL covered 90% of patient examinations in European Radiology, 60% of the collective dose from medical sources and approximately 50% of the collective dose to European citizens from man-made sources. The SENTINEL co-ordination actions 'main' objective was to address the safety and efficacy issues which are common to all digital diagnostic imaging systems, including nuclear medicine. High-dose procedures and sensitive groups (such as children) were covered by the project. Specifically, the co-ordination action aimed: (1) to establish both physical and clinical image quality criteria and link the two, (2) to undertake a series of dosimetry studies to establish the reference levels for new procedures and (3) to develop good practice guidelines for radiation protection in digital imaging and produce training material.

Survey on performance assessment of cardiac angiography systems

Advances in imaging technology have facilitated the development of increasingly complex interventional cardiac equipment. Consequently, there is a need for definitive equipment requirements. The aim of the study is to assess the performances of different cardiac angiographic systems. A questionnaire was sent to centres participating in SENTINEL Project to collect dosimetry data (typical entrance dose rate in fluoroscopy and imaging mode), image quality evaluations (low and high contrast resolutions) and KAP calibration factors. Results from this survey could contribute to the explanation of patient dose variability in angiographic cardiac procedures and to derive reference levels for cardiac angiographic equipment performance parameters.

Staff dosimetry in interventional cardiology: survey on methods and level of exposure

In interventional cardiac procedures, staff operates near the patient in a non-uniformly scattered radiation field. Consequently, workers may receive, over a period, relatively high radiation doses. The measurement of individual doses to personnel becomes critical due to the use of protective devices and, as a consequence of the large number of methods proposed to assess the effective dose, great variability in monitoring programmes is expected among European countries. SENTINEL consortium has conducted a survey on staff dosimetry methods and on the level of staff exposure in 12 European cardiac centres demonstrating the urgent need to harmonise dosimetry methods. From the dosimetry survey, constraint annual effective dose of 1.4 mSv and Hp(0.07) over the protective apron of 14 mSv are proposed for the optimisation the exposure the most-exposed operator.

Patient dose in interventional radiology: a European survey

Patient doses for a few common fluoroscopy-guided procedures in interventional radiology (IR) (excluding cardiology) were collected from a few radiological departments in 13 European countries. The major aim was to evaluate patient doses for the basis of the reference levels. In total, data for 20 procedures for about 1300 patients were collected. There were many-fold variations in the number of IR equipment and procedures per population, in the entrance dose rates, and in the patient dose data (total dose area product or DAP, fluoroscopy time and number of frames). There was no clear correlation between the total DAP and entrance dose rate, or between the total DAP and fluoroscopy time, indicating that a number of parameters affect the differences. Because of the limited number of patients, preliminary reference levels were proposed only for a few procedures. There is a need to improve the optimisation of IR procedures and their definitions and grouping, in order to account for their different complexities.

Acceptance testing and QA of interventional cardiology systems

Interventional cardiology (IC) is a rapidly growing field of medical specialisation. Such procedures are complex and may subject patients and operators to higher levels of risk than those encountered in general radiology. Acceptance testing and quality assurance (QA) of radiological equipment, including IC equipment, is a requirement of the EU Medical Exposures Directive (MED) (97/43/EURATOM). In addition, the MED identifies interventional radiology as an area of special concern. This study presents the results of a survey of 17 IC systems (including several flat panel detector systems) in Irish hospitals. The results of the survey indicate large differences in patient doses between manufacturers for equivalent levels of measured image quality. In addition, all systems were found to have failed one or more acceptance tests, with 60% of systems demonstrating significant problems at acceptance testing. The results of the survey demonstrate the importance of acceptance testing and QA in IC. The results also provide baseline data, which may be used in the development of future QA guidelines.

Acceptance testing of fluoroscopy systems used for interventional purposes

This study presents the results of acceptance testing on 18 interventional fluoroscopy systems in Ireland. Acceptance testing and routine quality assurance (QA) of X-ray systems are the requirements of the EU Medical Exposures Directive (MED) and these requirements were subsequently implemented into Irish legislation. The MED states that special consideration should be given to the QA and dose assessment of high dose procedures such as interventional fluoroscopy. Owing to the advances in fluoroscopy technology, it has been found that comprehensive testing of interventional systems proves challenging in a busy hospital environment. A number of recurrent problems have been identified and are presented.

Equipment standards for interventional cardiology

Interventional radiology has seen rapid growth in cardiology and represents an alternative to hazardous surgery. Recently there has been a substantial growth in the number of procedures being performed and interventional cardiology (IC) procedures are the most common interventional procedures in Europe. Advances in imaging technology have facilitated the development of increasingly complex radiological IC equipment. Currently, the technology is developing at a rate ahead of supporting research, equipment standards and a regulatory framework. International standards play a key role in the design, manufacture and performance of radiological IC equipment. A survey of 12 IC systems (15 imaging chains) was conducted in Irish hospitals. The aim of the study was to assess the imbalance between rapidly advancing technology and existing standards and to propose recommendations for new IC equipment standards. The results demonstrate the need for definitive equipment requirements and standardisation in the design, manufacture, acceptance and maintenance of IC equipment.

Subjective and objective measures of image quality in digital fluoroscopy

There are numerous methods for assessing image quality in diagnostic X ray. In our study we assessed how imaging quality assurance methods perform in practice. Physics assessments were based on IPEM protocols using Leeds test objects. Clinical assessment was based on a questionnaire. A total of 15 systems in three European locations were assessed, covering a range of image intensifier-TV digital fluoroscopy units. Analysis of 274 clinical questionnaires showed that clinical and physics assessments did not place systems in the same order, based on a given image quality parameter. In almost all the comparisons, low level correlation was measured for statistical comparison of rank order (rs < 0.3). However, broad agreement was observed between physics and clinical assessments for image quality associated with contrast and noise. This study emphasises the importance of maintaining links with clinical assessment, when developing quality assurance metrics, and measuring the mutual performance of clinical and physical assessments of image quality.

Q fever in Ireland. A seroprevalence study of exposure to Coxiella burnettii among Department of Agriculture workers

OBJECTIVES

To estimate the risk of exposure to Coxiella burnettii among 'at risk' workers in Ireland.

METHODS

A cross-sectional seroprevalence study, using the complement fixation technique (CFT), was carried out among technical and support staff of the Department of Agriculture in Ireland (n = 375). Participants were divided into low- (n = 34), moderate- (n = 158) and high-risk (n = 83) groups according to the likelihood of occupational exposure. A result of <1:8 on CFT was accepted as normal, i.e. no evidence of past exposure to the causative organism, C. burnettii. Participants with titres of 1:16 were clinically assessed for evidence of past or present infection and interviewed regarding the possibility of non-occupational exposure.

RESULTS

The participation rate was 75% (n = 281). Overall, 24 of the 281 participants (8.5%, 95% confidence interval = 5.6-12.4%) tested positive (titres = 1:8). No statistically significant difference existed between the three groups (low, 8.8%; moderate, 9.5%; high, 7.2%). Of those reviewed (n = 10), no evidence of either past or present clinically significant illness was detected. Possible non-occupational exposure was identified in two cases.

CONCLUSION

Laboratory evidence of past exposure to Q fever is common amongst readily identifiable 'at risk' occupational groups in Ireland, and appropriate preventative steps are warranted. Employees who do not have direct exposure to animals or animal products, but who work in a high risk environment appear to have a similar risk of exposure C. burnettii. Although clinical illness appears to be rare, health care workers should consider the possibility of Q fever in cases of unexplained illness arising in those working in 'high risk' environments.

[Establishment of minimum medical geographic information systems database in China]

OBJECTIVE

To establish a minimum medical geographic information systems (GIS) database as a spatial decision supporting system (SDSS), and to use the database into public health practice in China.

METHODS

Spatial data collected from different sources were standardized as decimal degree format, including: (1) satellite images covering areas of China; (2) digital maps of China in vector files; (3) diseases database and relevant models.

RESULTS

Necessary satellite images for the database have been collected from NOAA AVHRR, Landsat TM, etc., including the normalized difference vegetation index (NDVI) images from AVHRR, earth surface temperature images from AVHRR, GTOPO30 DEM images from USGS and landuse images from USGS. The digital vector files for GIS analysis were collected including political (county, provinces, country) boundaries file, environmental (drainage, land cover, soil type) vector file, population data and climate data; Data on diseases mainly generated from survey or case reporting. Relevant models on transmission of Schistosoma japonicum and Plasmodium vivax, and models of Oncomelania hupensis and Anophores sinansis were developed, and the relevant environmental factors related to incidence of cancers were mapped, to test and verify those database.

CONCLUSION

The database unified the data from different sources for users. Minimum medical data included in the database could be used in the practice of public health. It is expected that this database be used in a wider range.

A cross-sectional study of employer and employee occupational health needs and priorities within the Irish Civil Service

BACKGROUND

This study aimed to establish how important an occupational health unit (OHU) is to its clients, and to identify the perceived needs and priorities for such a service.

METHODS

A cross-sectional postal survey of a stratified, randomly selected group of employees (n = 760) and all human resources (HR) managers (n = 34) was conducted in the Irish Civil Service. Each participant was requested to rate the overall importance of the OHU and to prioritize eight proposed functions for the unit: medical surveillance, general health education, pre-employment/promotion medical assessments, ill-health retirement assessments, return-to-work (after sick leave) assessments, occupational health education, research, and general medical screening. The results were analysed according to age group, gender, grade and occupation.

RESULTS

There was a response rate of 69% from employees and 74% from personnel managers. Significantly more HR managers than employees (92 versus 81%) thought an occupational health service was either important or very important. There were also differences in prioritization of functions by employees and HR managers. HR managers prioritized those functions concerned with assessing individuals' fitness for work, notably pre-employment/promotional health assessments, whereas employees consider group-directed 'preventative' functions to be more important, i.e. general medical screening, health education and medical surveillance. Both sets of opinions are not mutually exclusive, and considerable overlap exists, notably in the areas of occupational and general health education.

Effects of prostaglandin E(2) on proliferation and apoptosis of epithelial ovarian cancer cells

OBJECTIVE

There is strong evidence indicating that prostaglandins (PG) and their synthesizing enzyme cyclooxygenase-2 (COX-2) play an important role in tumorigenesis. The purposes of the present study were to determine the pattern of expression of COX-2 and the effect of PG treatment on proliferation and apoptosis in epithelial ovarian cancer cells.

METHODS

Two epithelial ovarian cancer cell lines, MDAH-2774 and SKOV3, were grown in flasks to confluence. Cells were then treated with exogenous dimethyl prostaglandin E(2) (dmPGE(2)) at increasing concentrations of 0-10 microg/mL. Total RNA was extracted from cells at different treatment doses and subjected to reverse transcriptase-polymerase chain reaction for the semiquantitative analysis of COX-2, Bcl-2, and bax expression. Flow cytometry was performed to assess effect of treatment on the cell cycle. The TUNEL assay was used to assess apoptosis.

RESULTS

We found that COX-2 was constitutively expressed in the MDAH-2774 and SKOV3 epithelial ovarian cancer cells as determined by detection of a 304-bp amplified fragment using specific primers for the COX-2 gene. Treatment of both cell lines with dmPGE(2) resulted in dose-dependently higher expression of COX-2, Bcl-2, and bax mRNA compared with untreated cells. These changes were associated with an increase in the proliferative fraction and with a simultaneous reduction in apoptosis.

CONCLUSIONS

Prostaglandin E(2) stimulated proliferation and reduced apoptosis in epithelial ovarian cancer cells. These effects were associated with overexpression of COX-2 and an increase in the ratio of Bcl-2:bax mRNA.

Beneficial effects of intensive therapy of diabetes during adolescence: outcomes after the conclusion of the Diabetes Control and Complications Trial (DCCT)

OBJECTIVE

The Diabetes Control and Complications Trial (DCCT) demonstrated that intensive therapy of type 1 diabetes mellitus reduces the risk of development and progression of microvascular complications. The Epidemiology of Diabetes Interventions and Complications (EDIC) study assessed whether these benefits persisted after the end of DCCT. Results for the adolescent DCCT cohort are reported here.

STUDY DESIGN

Of the DCCT adolescent cohort (n = 195), 175 participated in EDIC, 151 had fundus photography, and 156 had albumin excretion rate measured at year 3 or 4. The odds of progression of retinopathy and albuminuria from closeout of the DCCT until EDIC year 4 were assessed.

RESULTS

In contrast to the 7.4 years of the DCCT, during which mean hemoglobin A(1c) levels were significantly lower with intensive therapy than conventional therapy (8.06% vs 9.76%; P <.0001), the subsequent first 4 years of EDIC had mean hemoglobin A(1c) levels that were similar between the former intensive and the former conventional groups (8.38% vs 8.45%). However, the prevalence of worsening of 3 steps or more in retinopathy and of progression to proliferative or severe nonproliferative retinopathy were reduced by 74% (P <.001) and 78% (P <.007), respectively, in the former intensive therapy group compared with the former conventional group.

CONCLUSIONS

These findings provide further support for the DCCT recommendation that most adolescents with type 1 diabetes receive intensive therapy aimed at achieving glycemic control as close to normal as possible to reduce the risk of microvascular complications.

Recombinant human antibody single chain variable fragments reactive with Candida albicans surface antigens

A combinatorial phage display library expressing human immunoglobulin heavy and light chain variable regions was used to identify phage clones capable of binding to the surface of Candida albicans blastoconidia. Single chain antibody variable fragments (scFv) derived from three clones detected C. albicans antigens by indirect immunofluorescence assay (IFA), enzyme-linked immunosorbent assay (ELISA), and Western blotting. The antigens detected were conserved among different strains of C. albicans and several other Candida species. Two scFv clones detected antigens specifically expressed by C. albicans blastoconidia; the third detected antigens in both blastoconidia and filamentous forms of C. albicans. The antigens containing the epitopes recognized by all three scFv could be extracted from blastoconidia by dithiothreitol, suggesting attachment to the cell wall via sulfhydryl bonds. Epitope detection by the scFv was sensitive to treatment of C. albicans blastoconidia with sodium periodate, but not proteinase K, indicating the cognate epitopes were composed of carbohydrate. Antigenic determinants for each of the three scFv were detected by immunohistochemical staining of skin sections from a model of cutaneous candidiasis, demonstrating expression in vivo. Through selection for the ability to bind intact organisms, the phage display system provides a means to rapidly identify monoclonal binding ligands to Candida surface antigens. Being entirely human, mature antibodies generated from the scFv have potential utility in the treatment of candidiasis.