Effect of biological fouling on passive collectors used to estimate fish recruitment

Evidence is provided that biofouling of artificial substrata for estimating recruitment of nearshore reef fishes influences recruitment, and it is recommended that investigators consider the effects of fouling when estimating recruitment over space and time.

From the bush to the big smoke--development of a hybrid urban community based medical education program in the Northern Territory, Australia

CONTEXT

The Northern Territory (NT) of Australia is a unique setting for training medical students. This learning environment is characterised by Aboriginal health and an emphasis on rural and remote primary care practice. For over a decade the NT Clinical School (NTCS) of Flinders University has been teaching undergraduate medical students in the NT. Community based medical education (CBME) has been demonstrated to be an effective method of learning medicine, particularly in rural settings. As a result, it is rapidly gaining popularity in Australia and other countries. The NTCS adopted this model some years ago with the implementation of its Rural Clinical School; however, urban models of CBME are much less well developed than those in rural areas. There is considerable pressure to better incorporate CBME into medical student teaching environment, particularly because of the projected massive increase in student numbers over the next few years. To date, the community setting of urban Darwin, the NT capital city, has not been well utilised for medical student training.

ISSUE

In 2008, the NTCS enrolled its first cohort of students in a new hybrid CBME program based in urban Darwin. This report describes the process and challenges involved in development of the program, including justification for a hybrid model and the adaptation of a rural model to an urban setting. Relationships were established and formalised with key partners and stakeholders, including GPs and general practices, Aboriginal medical services, community based healthcare providers and other general practice and community organisations. Other significant issues included curriculum development and review, development of learning materials and the establishment of robust evaluation methods.

LESSONS LEARNT

Development of the CBME model in Darwin posed a number of key challenges. Although the experience of past rural programs was useful, a number of distinct differences were evident in the urban setting. Change leadership and inter-professional collaboration were key strengths in the implementation and ongoing evaluation of the program. The program will provide important information about medical student training in urban community settings, and help inform other clinical schools considering the adoption of similar models.

Internal recycle to improve denitrification in a step feed anoxic/aerobic activated sludge system

During periods of low load (weekends and holidays) the Mangere wastewater treatment plant effluent has breached the summer consent conditions for total nitrogen. The purpose of this research was to determine if an internal recycle would improve nitrogen removal in the anoxic/aerobic activated sludge reactors sufficient to meet the summer resource consent standard. The recycle returned nitrate rich mixed liquor from the downstream aerobic zone back to the initial anoxic zone, thus potentially improving denitrification. A full scale trial showed that installation of the internal recycle on each RC would have satisfied the resource consent for total nitrogen in most cases over the three summer resource consent periods since the upgrade. However, further modifications of the internal recycle would be required to ensure that consent conditions were satisfied at all times and to improve the consistency of the results.

Down-regulation of ATM protein in HRS cells of nodular sclerosis Hodgkin's lymphoma in children occurs in the absence ofATMgene inactivation

The tumour component of classical Hodgkin's lymphoma (cHL), Hodgkin Reed-Sternberg (HRS) cells, are believed to be derived from germinal centre (GC) B cells but intriguingly display a characteristic loss of B cell receptor (BCR) expression. The precise mechanisms by which BCR-negative HRS cell progenitors survive negative selection during the GC reaction remain obscure. Individuals with ataxia telangiectasia, caused by biallelic inactivation of the DNA damage response gene, ataxia telangiectasia mutated (ATM), have a higher risk of cHL development. Here we show that, in contrast to normal GC B cells that expressed low but detectable ATM protein, ATM protein was not detected in HRS cells of 17/18 cases of paediatric cHL, all but one with nodular sclerosis (NS) subtype. A comprehensive analysis of the ATM gene in microdissected HRS cells of nine representative tumours showed no evidence of either loss of heterozygosity or consistent pathogenic mutations. Furthermore, bisulphite sequencing of the ATM promoter from HRS cells of five tumours also revealed the absence of hypermethylation. Since our microarray data suggested significantly reduced ATM transcription in HRS cells compared to GC B cells, we conclude that loss of ATM expression could be the result of alterations in upstream regulators of ATM transcription. Importantly, ATM loss in paediatric cHLs has clinical implications and could be potentially exploited to guide future, less toxic, tumour-specific treatments.

AIDIT and IMPACT: building research collaborations in targeted prostate cancer screening

AIDIT (Advancing International Co-operation and Developing Infrastructure for Targeted Screening of Prostate Cancer in Men with Genetic Predisposition) is a project funded by the Sixth Framework Programme of the European Community which is endeavouring to facilitate co-operation between European countries in the field of cancer research. The project also aims to raise awareness of familial prostate cancer among health professionals and the public within the associated candidate countries (ACCs) and new member states of the European Union (EU). AIDIT will focus on linking clinical and research teams in the ACCs and new member states with the IMPACT Consortium (Identification of Men with a genetic predisposition to ProstAte Cancer: Targeted screening in BRCA1/2 mutation carriers and controls), an international team investigating screening and diagnosis for men with a genetic risk of prostate cancer predisposition genes BRCA1 or BRCA2). Cancer research has been targeted as a high priority for the European Community; however, research is most successful when centralised and well coordinated, avoiding the duplication and fragmentation associated with smaller, isolated studies. AIDIT will consolidate the current IMPACT consortium and allow research partners from across the world to benefit from shared knowledge and experience. To date, the AIDIT team has established a website to facilitate communication between project collaborators (www.impact-study.co.uk), has been represented at several international meetings and has facilitated a conference for the IMPACT study to bring together international research teams, clinicians and policy makers.

Surveillance of insecticide resistance in head lice using biochemical and molecular methods

Treatment of head louse infection is primarily through topical insecticides. However, there is growing evidence of resistance. A representative population sample was tested using biochemical and molecular methods; it was shown that, in Wales, treatments containing pyrethroids are likely to be less effective in controlling head louse infection than those containing organophosphates.

Discrimination of glaucomatous optic neuropathy by digital stereoscopic analysis

PURPOSE

To evaluate the diagnostic power of a novel digital stereoscopic imaging system in the diagnosis of glaucomatous optic neuropathy.

DESIGN

Prospective cross-sectional analysis of the diagnostic accuracy of digital stereoscopic optic disc analysis in the diagnosis of glaucomatous optic neuropathy exhibiting mild to moderate field loss.

PARTICIPANTS

Fifty-two patients with open-angle glaucoma and 54 normal individuals were recruited. The presence of a reproducible visual field loss characteristic of glaucoma was used as the reference standard for the presence of glaucoma independent of the optic nerve head appearance. Patients were excluded if the optic disc, fundus, or visual field indicated other disease. One eye from each patient and individual was included in the study, the eye with the least field loss and a randomly designated normal eye, respectively.

METHODS

Simultaneous stereoscopic optic disc photography was performed on each specified eye. Three experienced observers viewed the resultant stereoscopic image of each nerve head using a Z screen, recorded a subjective clinical diagnosis, and undertook digital stereoscopic planimetry. Separate linear regression analysis was performed, post hoc, from the planimetric results for each observer of the logarithm of neuroretinal rim (NRR) against optic disc area derived from each normal eye. Eyes with NRR areas below the 95th prediction interval of the normal cohort were then classified as glaucomatous.

MAIN OUTCOME MEASURES

Sensitivity and specificity for the detection of glaucomatous optic neuropathy.

RESULTS

With subjective stereoscopic analysis, sensitivity for glaucoma detection among the 3 observers was 80.8%, 76.9%, and 90.4%, with respective specificities of 94.4%, 79.6%, and 79.6%. Regression analysis of the NRR in 30 degrees segments gave sensitivities between 69.2% and 80.8% and specificities between 83.3% and 90.7%. A combination of the subjective and quantitative analysis did not significantly improve discrimination.

CONCLUSIONS

The subjective analysis of digital stereoscopic images provides a useful method for the discrimination of normal and glaucomatous optic nerves. Planimetric analysis does not significantly improve the diagnostic precision of this technique.

The hydroxyapatite-coated JRI-furlong hip. Outcome in patients under the age of 55 years

We present the clinical and radiographic outcome of 68 consecutive primary total hip replacements performed in 54 patients under the age of 55 years using a hydroxyapatite-coated femoral component and threaded cup with a modular ceramic head (JRI-Furlong). We reviewed 62 (91%) hips at a median follow-up of 8.8 years (5 to 13.8) after implantation; six (9%) were lost to follow-up. At review there had been four (6%) revisions but only one for aseptic loosening (acetabulum). Radiographic review of the remaining hips did not identify any evidence of femoral or acetabular loosening. The median Harris and Merle d'Aubigné and Postel hip scores were 95.9 (42.7 to 100) and 17 (3 to 18) respectively. The JRI-Furlong hip gives promising functional and radiographic results in young patients in the medium term.

The hydroxyapatite-coated JRI-Furlong hip

We present the clinical and radiographic outcome of 68 consecutive primary total hip replacements performed in 54 patients under the age of 55 years using a hydroxyapatite-coated femoral component and threaded cup with a modular ceramic head (JRI-Furlong). We reviewed 62 (91%) hips at a median follow-up of 8.8 years (5 to 13.8) after implantation; six (9%) were lost to follow-up. At review there had been four (6%) revisions but only one for aseptic loosening (acetabulum). Radiographic review of the remaining hips did not identify any evidence of femoral or acetabular loosening. The median Harris and Merle d’Aubigné and Postel hip scores were 95.9 (42.7 to 100) and 17 (3 to 18) respectively. The JRI-Furlong hip gives promising functional and radiographic results in young patients in the medium term.

The treatment of acute dacryocystitis using laser assisted endonasal dacryocystorhinostomy

AIMS

To determine whether acute dacryocystitis complicated by abscess formation can be successfully treated using laser assisted endonasal dacryocystorhinostomy.

METHODS

A protocol was adopted for the management of acute dacryocystitis presenting to an ophthalmology department. All patients were assessed jointly by an ophthalmologist and otolaryngologist for their suitability for primary internal drainage via a nasal endoscopic approach. All suitable patients during the study period August 1999 to November 2000 were managed by intravenous antibiotics and holmium:YAG laser dacryocystorhinostomy.

RESULTS

Nine patients were studied (mean age 72 years (range 38-82 years), three men, six women). A history of chronic epiphora was found in 78% of patients, and recurrent nasolacrimal infections in the same 78%. Resolution of symptoms and signs of acute dacryocystitis occurred in all nine patients. No recurrence of acute dacryocystitis occurred during the median follow up period of 11 months (range 6-31 months). Ostium patency defined as the absence of epiphora and the observation of irrigated lacrimal fluorescein at the ostium was achieved in 67% of patients. Epiphora recurred in 33% of cases.

CONCLUSION

Laser assisted endonasal dacryocystorhinostomy is an effective primary treatment in cases of acute dacryocystitis complicated by abscess formation. In addition, pre-existing symptoms of epiphora and recurrent nasolacrimal infections are relieved in the majority of patients.

Relationship between Behavioral Recovery from Unilateral 6-OHDA Lesion of the Substania Nigra and Changes in the Tuberomammillary-Striatal Projection as Measured by HRP-Labelling

The tuberomammillary nucleus (TM) is the only known neuronal cell group in the brain which contains histamine. There is evidence for a reciprocal relationship between the effects of histamine and dopamine on behavior. A unilateral lesion of dopamine cells in the Substantia Nigra (SN) results in asymmetrical behavior, and recovery from this asymmetry was previously found to be associated with asymmetrical changes in the nigro-striatal projection as determined by anatomical tracing technique. In view of the apparent opposing interaction between the TM and the SN, we examined whether the tuberomammillary-striatal projection also shows changes after a unilateral lesion of the SN. Rats had 6-OHDA injected into one substantia nigra and were tested for behavioral asymmetry over a 15 day period. Horseradish peroxidase (HRP) was then deposited in the caudate-putamen (CPU) ipsilateral to the lesion. Controls devoid of a lesion had the tracer deposited in either the right of left CPU. More HRP-labeled cells were found in the anterior part of TM ipsilateral to the lesion in the animals which failed to recover from lesion-induced asymmetry in turning behavior, as compared to normal controls or animals which showed behavioral recovery. The labeled cells in the anterior part of the ipsilateral TM were smaller in animals examined 15 days after the lesions than in the control animals. The results indicate an increase in HRP uptake or transport in the anterior part of the tuberomammillary-striatal projection predominantly ipsilateral to the lesion in animals which failed to recover from lesion induced asymmetry. Previously, we had found an opposite effect in the nigro-striatal projection, namely an increase in HRP uptake or transport only in animals which recovered from their lesion induced asymmetry. The results are discussed in terms of the evidence for a reciprocal relationship between the TM- and SN-striatal systems.