The evolution of white matter microstructural changes after mild traumatic brain injury: A longitudinal DTI and NODDI study.

Neuroimaging biomarkers that can detect white matter (WM) pathology after mild traumatic brain injury (mTBI) and predict long-term outcome are needed to improve care and develop therapies. We used diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) to investigate WM microstructure cross-sectionally and longitudinally after mTBI and correlate these with neuropsychological performance. Cross-sectionally, early decreases of fractional anisotropy and increases of mean diffusivity corresponded to WM regions with elevated free water fraction on NODDI. This elevated free water was more extensive in the patient subgroup reporting more early postconcussive symptoms. The longer-term longitudinal WM changes consisted of declining neurite density on NODDI, suggesting axonal degeneration from diffuse axonal injury for which NODDI is more sensitive than DTI. Therefore, NODDI is a more sensitive and specific biomarker than DTI for WM microstructural changes due to mTBI that merits further study for mTBI diagnosis, prognosis, and treatment monitoring.

Does antibody binding to diverse antigens predict future infection?

We studied diverse antigen binding in hosts and the outcome of parasitism. We used captive-bred F1 descendants of feral rock pigeons (Columba livia) challenged with blood-feeding flies (Hippoboscidae) and a protozoan parasite (Haemoproteus). Enzyme-linked immunosorbent assays (ELISAs) and immunoblots were used to test (i) whether pre-infection IgY antigen binding predicts parasite fitness and (ii) whether antigen binding changes after infection. Assays used extracts from three pigeon parasites (northern fowl mite, Salmonella bacteria and avian pox virus), as well as nonparasitic molecules from cattle, chicken and keyhole limpet. Binding to hippoboscid and S. enterica extracts were predictive of hippoboscid fly fitness. Binding to extracts from hippoboscids, pox virus and nonparasitic organisms was predictive of Haemoproteus infection levels. Antigen binding to all extracts increased after parasite challenge, despite the fact that birds were only exposed to flies and Haemoproteus. Immunoblots suggested innate Ig binding to parasite-associated molecular markers and revealed that new antigens were bound in extracts after infection. These data suggest that host antibody binding to diverse antigens predicts parasite fitness even when the antigens are not related to the infecting parasite. We discuss the implications of these data for the study of host-parasite immunological interaction.

Comparative off-host survival of larval Rocky Mountain Wood Ticks (Dermacentor andersoni) collected from ecologically distinct field populations.

Dermacentor andersoni (Ixodida: Ixodidae) Stiles, also known as the Rocky Mountain Wood Tick (RMWT), is found throughout the western United States and transmits pathogens of importance to human and animal health. The distributions and activity patterns of RMWTs are shaped by regional climatic variation. However, it is unknown if responses to climatic variation differ across the tick's geographical range. The objective of this narrow study was to test the hypothesis that the responses of RMWTs to abiotic conditions [e.g. temperature and RH (relative humidity)] vary among populations. We collected RMWTs from ecologically distinct field sites in the states of Montana and Oregon (USA). In the laboratory, we tracked weekly survival of tick larvae under four combinations of RH (75% and 98%) and temperature (26 and 32 °C) that reflected the range of conditions observed in the source habitats during spring-summer. For both populations, larval survival time decreased at the higher ambient temperature (50% mortality 1-2 weeks earlier). Differences in RH did not affect the survival time of larvae from Oregon. By contrast, the survival time of larvae from Montana decreased at the lower RH (50% mortality 1 week earlier). These data suggest that the tolerance limits for water stress may differ among populations of D. andersoni.

Beak condition and cage density determine abundance and spatial distribution of northern fowl mites, Ornithonyssus sylviarum, and chicken body lice, Menacanthus stramineus, on caged laying hens.

Adult White Leghorn hens (Hy-Line strain W-36) were inoculated with either northern fowl mites or chicken body lice, and the ectoparasite populations were monitored over periods of 9 to 16 wk. Two beak conditions (beak trimmed or beak intact) and 2 housing densities (1 or 2 hens per 25 × 31 cm suspended wire cage) were tested. Populations of both ectoparasites were at least 10 times lower on beak-intact hens compared with populations on beak-trimmed hens. Cage density did not influence mite numbers, but higher numbers of lice (2 to 3 times) developed on hens held at the higher cage density. Louse distribution on the body and louse population age structure were also influenced by host beak condition. Beak-intact hens had a higher proportion of lice under the wings, whereas beak-trimmed hens had the majority of lice on the lower abdomen. Louse populations on beak-trimmed hens also comprised relatively more immature stages than populations found on beak-intact hens. The effects are likely related to decreased grooming efficiency by beak-trimmed hens and, in the case of lice, the higher host density. The high mite and louse populations on most commercial caged laying hens are probably a direct result of beak trimming. However, selection of more docile breeds that can be held without trimming may allow the hens themselves to reduce ectoparasites below economically damaging levels. This could benefit producers, animal welfare advocates, and human health by reducing 1) costs of beak trimming, 2) pesticide treatment costs (including human and bird chemical exposure concerns), and 3) objections to beak trimming from the animal welfare community.

An evaluation of the medical training application service as experienced by defence medical service medical officers.

OBJECTIVES: In 2007 Defence Medical Service (DMS) Medical Officers (MOs) applying to train within hospital based specialities were selected using the Medical Training Application Service (MTAS). Recognising the problems being reported about MTAS, the Defence Postgraduate Medical Deanery (DPMD) conducted an evaluation in order to assess whether DMS MOs had also experienced problems with the MTAS process. METHODS: DMS MO applicants were sent an email questionnaire, requesting both graded (Likert scale) and narrative responses, to gauge their opinion about the application service. The questionnaire covered the technical aspects of the process, the support available and the ability to demonstrate appropriate knowledge and skills. RESULTS: Only 42 responses (32%) were received. However, having considered areas of potential bias, the graded questionnaire results and thematic analysis of the narrative responses showed a clear consensus amongst the applicants in many areas. More than three quarters (78%) of DMS applicants criticised the opportunity to record their abilities and achievements, and 91% recorded that the questions were unable to differentiate between candidates. These views were mirrored in the narrative responses, with more than 130 statements covering five topic areas highlighting areas for improvement. Strong support was recorded for the work and advice provide by DPMD in support of the candidates. CONCLUSIONS: DMS MOs presented very negative opinions of their experiences of MTAS, highlighting their perceptions that they were unable to record their particular skills and experiences and that the questions were unable to discriminate between specialties. Particular difficulties were reported in presenting non-NHS experiences and skills.

An Evaluation of the Medical Training Application Service as experienced by Defence Medical Service Medical Officers.

OBJECTIVES: In 2007 Defence Medical Service (DMS) Medical Officers (MOs) applying to train within hospital based specialities were selected using the Medical Training Application Service (MTAS). Recognising the problems being reported about MTAS, the Defence Postgraduate Medical Deanery (DPMD) conducted an evaluation in order to assess whether DMS MOs had also experienced problems with the MTAS process. METHODS: DMS MO applicants were sent an email questionnaire, requesting both graded (Likert scale) and narrative responses, to gauge their opinion about the application service. The questionnaire covered the technical aspects of the process, the support available and the ability to demonstrate appropriate knowledge and skills. RESULTS: Only 42 responses (32%) were received. However, having considered areas of potential bias, the graded questionnaire results and thematic analysis of the narrative responses showed a clear consensus amongst the applicants in many areas. More than three quarters (78%) of DMS applicants criticised the opportunity to record their abilities and achievements, and 91% recorded that the questions were unable to differentiate between candidates. These views were mirrored in the narrative responses, with more than 130 statements covering five topic areas highlighting areas for improvement. Strong support was recorded for the work and advice provided by DPMD in support of the candidates. CONCLUSIONS: DMS MOs presented very negative opinions of their experiences of MTAS, highlighting their perceptions that they were unable to record their particular skills and experiences and that the questions were unable to discriminate between specialties. Particular difficulties were reported in presenting non-NHS experiences and skills.

Culicoides bottimeri as a vector of Haemoproteus lophortyx to quail in California, USA.

Arthropod sampling via periodic direct bird examination and regular light trapping was conducted between June 2000 and October 2002 to survey for potential vectors of Haemoproteus lophortyx to nonnative, captive-raised bobwhite quail (Colinus virginianus) in northern California, USA. Examination of individual bobwhite quail (from 5 weeks of age through adult, total n=76) was conducted on several dates during the transmission period (June-October). No ectoparasites, including hippoboscid flies (reported as Haemoproteus vectors to wild quail in early literature), were collected from the birds. Trapping with ultraviolet light suction traps near the quail revealed nine species of biting midges (Culicoides spp.). Of these, 94% were C. bottimeri, which was abundant near the birds, and 65% of collected C. bottimeri were engorged with blood. C. bottimeri adult activity began in late-April, slightly before the onset of disease in the quail. Activity peaked between July and late-September, coincident with maximum reported transmission, and adult activity ceased by early-November. Nonengorged C. bottimeri had a parity rate of 43.6% overall, suggesting excellent survival for biological transmission of a pathogen like H. lophortyx. A controlled study was done injecting a macerated slurry of pooled, nonengorged, wild-caught C. bottimeri into the peritoneum of 1-day-old bobwhite quail hatchlings held in insect-proof containers. Blood smears 13-19 days later confirmed H. lophortyx infection in zero controls but all insect-injected quail. Biting midges, especially C. bottimeri, transmit H. lophortyx to captive quail and probably are the dominant vector to native California quail (Callipepla californica) as well.

A survey of the provision of educational supervision in occupational medicine in the Armed Forces.

OBJECTIVE: The aim of this study was to assess whether balanced educational supervision was being provided for occupational medicine (OM) specialist registrars (SpRs) in the Armed Forces and to consider the effectiveness of current supervision. METHODS: Anonymized postal questionnaires, using Likert five-point response scales, were sent to Service OM SpRs and their educational supervisors (Ed Sup) to assess the degree of understanding of the purpose, effectiveness and organization of the educational supervision being provided. RESULTS: Completed questionnaires were returned from 35 (92%) specialists and 14 (61%) SpRs. Less than a third of the specialists were involved as Ed Sup and only three (11%) had undergone any formal medical education training. There was an agreement about the purpose and effectiveness of educational supervision between both the groups, though there appeared to be a bias towards providing supportive functions with patient management and educational components scoring less highly. CONCLUSIONS: A high response rate enabled an accurate assessment of OM supervision practices in the Armed Forces to be made. There was agreement over the relative effectiveness, importance and coverage of educational supervision, though this was being provided by a relatively small group of OM specialists, few of whom had undertaken any formal medical education training. The supervision provided also appeared to be biased towards providing supportive functions rather than patient management and educational components of training, which may result in an unbalanced training for the SpRs. Having assessed the relatively close-knit service OM community, there would be value in seeing whether similar patterns prevail in the wider OM community.

An audit of Territorial Army Medical Grades on presentation for mobilisation and full time reserve service at RTMC Chilwell.

An audit was carried out on a cohort of Territorial Army (TA) personnel passing through RTMC in order to assess the quality of their previous medical assessments compared to that undertaken at the time of their mobilisation. The results confirmed the high downgrading rate (18%) amongst TA personnel compared to previous studies that identified grading error rates of 6-6.5% amongst Regular Army personnel. Errors in the entry medical assessments for TA personnel were also identified in nearly half (44%) of records examined. Possible solutions are identified through improved education of examining medical officers and by increasing the pre-deployment time available to obtain specialist referrals. A case is also made for having improved access to previous medical information, both to improve the quality of the pre-deployment medical screening and to ensure appropriate continuity of care for deployed TA personnel.

Tetanus immunisation in hypersensitive individuals.

We report on a case of an officer cadet who was inadvertently allowed to commence training with a history suggestive of hypersensitivity to tetanus immunisation and who, eventually, successfully underwent a graduated immunisation regimen. This case combines a search for good evidence with the extraordinary complexities of military medical management and the law. It is a lesson in all three.

Occupational health development in the Army.

Occupational Health (OH) in the Army is provided as part of an integrated primary healthcare service. When compared to the International Labour Organisation criteria for the provision of OH, it can be seen that the Army provides all of the OH elements expected in a large national organisation. However, there is a need to enhance the clinical element of the service and to provide a focus for implementing OH policy at unit level. The use of qualified OH nurses based at GP group practices and providing a visiting service to units would rectify this balance as this would enable workplace assessments to be carried out on a regular basis, enhance the ability to carry out occupational health assessments and facilitate health surveillance data collection. The result would be the improved delivery of OH services to Army personnel, thus helping to maximise the number of soldiers and officers fit to carry out their military duties.

Long-term follow-up of patients presenting to adult nephrologists with chronic pyelonephritis and 'normal' renal function.

We studied the natural history, and therefore prognosis, of patients with chronic pyelonephritis presenting to adult nephrologists with a plasma or serum creatinine <90 mmol/l. From the Newcastle chronic pyelonephritis database, 255 patients with radiologically-proven disease were reviewed. Median follow-up was 95 months (95%CI 82. 3-109.3). Plasma creatinine was < or =90 micromol/l (P(Cr)< or =90 group) at presentation in 138. At presentation, hypertension, bilateral disease and proteinuria were less frequent in the P(Cr)< or =90 group (hypertension 19% vs. 32%, p<0.05; bilateral disease 25% vs. 70%, p<0.001; proteinuria 18% vs. 60%, p<0.001). With the exception of two patients, the renal prognosis of this group was excellent. Patients over the age of 18 years presenting to adult nephrologists with a diagnosis of chronic pyelonephritis and a creatinine < or =90 micromol/l can be reassured that the chances of developing end-stage renal failure in the future are very small. Most could be referred back to their general practitioner for long-term follow-up.

Skeletal growth estimation using radiographic image processing and analysis.

An automated knowledge-based vision system for skeletal growth estimation in children is reported in this paper. Images were obtained from hand radiographs of 32 male and 25 female children of age 1-16 yr. Phalanx bones were automatically localized and segmented using hierarchical inferences and active shape models, respectively. A number of shape descriptors were obtained from the segmented bone contour to quantify skeletal growth. From these descriptors, a feature vector was selected for a regression model and a Bayesian estimator. The estimation accuracy was 84% for females and 82% for males. This level of accuracy is comparable to that of expert pediatric radiologists, which suggests that the proposed approach has a potential application in pediatric medicine.

A pilot study of J95 in secondary care in Bosnia.

The Army's morbidity reporting system J95 was fashioned into a secondary care variant and a pilot study conducted in Multinational Division South West (MND SW) during Operation Resolute 2. Some codes were modified, in keeping with the concurrent primary care J95a amendment, which included separating 'Other Injury' event codes further into 'Sports Injuries' and 'Other Injuries'. The collection system encompassed both out-patient and in-patient data and appropriate disposal categories such as 'admit' and 'length of stay' were introduced. Participating units included the Hospital Squadron at Sipovo, the Hospital facility at Tomislavgrad and, via a liaison officer, UK admissions and referrals to the Force Hospital near Split. A four month period of compatible data was found. Over this period 1,410 personnel (42.2/1,000/month) first attended out-patients with 337 requiring subsequent attendances (10.1/1000/month) and there were 425 admissions (12.7/1,000/month) from an average force level of 8,340 personnel. Nearly half the patients seen (49%) had orthopaedic problems and this group provided over half of the admissions (54%) and the bed occupancy (53%). There was a sizeable out-patient work load for the physician (28%). The pilot study showed that a J95 surveillance mechanism in secondary care was possible and informative. It gave indications of the impact of morbidity on the medical services and could help shape medical manning for future operations. It would be possible to adopt such a system in both the peacetime setting and in an international operational setting--in keeping with its primary care partner. It is recommended that J95 secondary variant should be continued on operations.

J95 health surveillance in Multinational Division South West (Bosnia): July-November 1996.

A modified version of the J95 morbidity reporting system, called J95a, was used in the Multinational Division South West (MND SW) during Operation Resolute 2. The broad scope of the 'Other Diseases' and 'Other Injuries' event codes were reduced, with codes being added for specific areas of interest which were 'ENT Problems', 'Sports Injuries' and 'Training Injuries'. Designated medical centres from all nations in the division reported on a monthly basis to HQ MND SW, enabling the morbidity profile to be monitored. The first attendance rates in MND SW were twice as high as those experienced by the whole of the British Army, though the rate of working days lost was only a third. Almost half (49%) of the working time lost in the division was due to injuries and orthopaedic problems. The disease and injury distribution showed considerable differences compared to the SHAPE planning figures, with the disease rates experienced being between half and two thirds of those predicted, whilst the injury rates experienced were between four and six times as high as those predicted. This evidence suggests that the planning figures need to be re-assessed for operations other than war. Further investigation into the aetiology of injuries causing loss of working time is recommended, particularly sports injuries and orthopaedic problems.

Hodgkin's disease: a population-adjusted clinical epidemiology study (PACE) of management at presentation. Northern Region Lymphoma Group.

Between January 1991 and December 1993, all newly-diagnosed patients with Hodgkin's disease in the Northern Health Region (population 3.08 million) were entered into a prospective population-based (PACE) study to assess the accuracy of staging at diagnosis, and to evaluate treatment and outcome. On histological review, 202 patients were confirmed to have Hodgkin's disease, an incidence of 2.2 per 100,000 per annum. Radiological review revealed that only 12% of patients were staged to recognized guidelines. In early-stage disease, treatment outcome was comparable to published results in Stage IA disease, but disappointing for Stage IIA. This was partly due to inadequate or inaccurate staging. In-built audit in the process was followed by the introduction and implementation of improved guidelines. Of younger patients (15-55 years) with 'poor-risk disease', 75% of the eligible population were entered into the appropriate randomized controlled trial. This intensive treatment has led to improved survival in this group over that which might be expected on four-drug therapy. The results of the randomized trial are not discussed as it is currently ongoing. This combined research/audit programme has resulted in greater standardization of care across a whole region, and confirms that the PACE (population-adjusted clinical epidemiology) approach facilitates the flow of information from research into practice and vice versa.

Computerized planimetry in the objective assessment of the antispasmodic effect of Zamifenacin in double contrast barium enemas.

A prospective, randomized, double-blind study was undertaken to evaluate Zamifenacin 30 mg (Pfizer Ltd), a novel, orally-administered, gut-specific muscarinic receptor antagonist, as an adjuvant to the double contrast barium enema examination (DCBE). Zamifenacin was compared with placebo in terms of side-effects and colonic tone. Analysis of colonic tone was carried out by two independent observers, using a subjective grading system and also by an objective method using computerized planimetry. Interobserver variability was also assessed. Zamifenacin is safe and well tolerated but at the prescribed dose is an ineffective antispasmodic for DCBE. Subjective assessment of colonic tone was shown to be of limited value whilst the objective analysis using computerized planimetry was reliable and highly reproducible.

Short communication: charge-coupled device camera optical density range enhancement and the effect on radiographic image segmentation.

A method is presented for the pre-processing of radiographs in the automated determination of skeletal maturity. By linearly combining several source images, a density range enhancement is obtained without the creation of edge artefacts. An increase of bit depth of 1 bit was obtained, and density range was improved by 1 OD.

How reliable are ultrasound measurements of renal length in adults?

Ultrasound assessment of patients with renal impairment commonly includes measurement of bipolar renal length. Reduction in length is considered to indicate chronic renal disease and is a factor in deciding whether to proceed to renal biopsy. To date, no published data are available on interobserver and intraobserver variation in sonographic renal length measurement in adults. Bilateral renal lengths were measured in 20 adult subjects, with no history of renal disease, by three experienced operators, on two separate occasions. Limits of agreement for replicate measurements by each ultrasonographer and for replicate measurements by each pair of ultrasonographers were determined. Values of repeatability (a measure of intraobserver variation) and reproducibility (a measure of interobserver variation) were calculated for all renal length measurements, and for right and left renal lengths separately. Results indicate that replicate renal length measurements differ by less than 1.85 cm in 95% of cases, and the magnitude of variations is similar when measurements are made by either single or different ultrasonographers, and are similar for right and left renal length measurements. This suggests that sonographic bipolar renal length measurements in normal adult kidneys are reasonably reliable. In diseased kidneys, however, in which identification of renal poles is difficult, interobserver and intraobserver variation may be much greater.