An analysis of the association between prostate cancer risk loci, PSA levels, disease aggressiveness and disease-specific mortality

BACKGROUND

Genome-wide association studies have identified multiple single-nucleotide polymorphsims (SNPs) associated with prostate cancer (PCa). Although these SNPs have been clearly associated with disease risk, their relationship with clinical outcomes is less clear. Our aim was to assess the frequency of known PCa susceptibility alleles within a single institution ascertainment and to correlate risk alleles with disease-specific outcomes.

METHODS

We genotyped 1354 individuals treated for localised PCa between June 1988 and December 2007. Blood samples were prospectively collected and de-identified before being genotyped and matched to phenotypic data. We investigated associations between 61 SNPs and disease-specific end points using multivariable analysis and also determined if SNPs were associated with PSA at diagnosis.

RESULTS

Seven SNPs showed associations on multivariable analysis (P<0.05), rs13385191 with both biochemical recurrence (BR) and castrate metastasis (CM), rs339331 (BR), rs1894292, rs17178655 and rs11067228 (CM), and rs11902236 and rs4857841 PCa-specific mortality. After applying a Bonferroni correction for number of SNPs (P<0.0008), the only persistent significant association was between rs17632542 (KLK3) and PSA levels at diagnosis (P=1.4 × 10(-5)).

CONCLUSIONS

We confirmed that rs17632542 in KLK3 is associated with PSA at diagnosis. No significant association was seen between loci and disease-specific end points when accounting for multiple testing. This provides further evidence that known PCa risk SNPs do not predict likelihood of disease progression.

Multi-centre variability of ISCEV standard ERGs in two normal adults

BACKGROUND

The reproducibility of an individual's full-field ERG between centres has not previously been investigated.

METHODS

ERGs were recorded using both silver thread and skin electrodes from the same two normal adult subjects at 15 UK centres using routine, local protocols and a highly standardised, 'ISCEV-specified' protocol matching the values specified in the ISCEV standard; where the ISCEV standard allows options, a single value was chosen.

RESULTS

Inter-ocular differences were small, and amplitudes were smaller for skin than silver thread electrodes. No centre produced outlying data points, and ERGs across all 15 centres were remarkably similar. Amplitude variability was less for local protocols (using LED flashes) than for the ISCEV-specified protocol using xenon flashes (22 vs. 24 %, p = 0.01), but peak time variability was less for the ISCEV-specified protocol (6.1 vs. 7.4 %, p = 0.001). Only the DA 0.01 ERG correlated with photometric variability. The bifidity of the DA 3 a-wave doubled its peak time variability compared with the DA 10 a-wave.

CONCLUSIONS

Inter-centre amplitude variability was typically within clinically significant thresholds, suggesting that inter-centre variability with suitable standardisation may not add more to total variability than inter-subject variability. Variability improvements gained by the tighter specifications of the ISCEV-specified protocol were possibly more than lost due to imprecisions of xenon flashtubes. Peak time variability was far lower than amplitude variability, corresponding with acceptable variability of biochemical assays. These results represent a vindication of the existence of an ERG standard and suggest that further standardisation would lend itself to greater reproducibility of ERGs worldwide.

Implementation of a nurse-delivered intravitreal injection service

PURPOSE

The purpose of this study was to introduce nurse-delivered intravitreal injections to increase medical retina treatment capacity.

METHODS

Indemnity, clinical governance, training, planning, and implementation issues were addressed. The outcome measures were patient safety, patient experience, and clinic capacity.

RESULTS

No serious vision-threatening complications were recorded in a consecutive series of 4000 nurse-delivered intravitreal injections. A Mann-Whitney test showed a significant increase in intravitreal injections (P=0.003) in the medical retina service after introduction of nurse-delivered intravitreal injections. The majority of patients accepted and were satisfied with a nurse-delivered intravitreal injection.

DISCUSSION

Nurse-delivered intravitreal injections appear safe, acceptable to patients, and are an effective means to increase intravitreal injection capacity in medical retina clinics.

Laminar distribution of the pathological changes in sporadic frontotemporal lobar degeneration with transactive response (TAR) DNA-binding protein of 43 kDa (TDP-43) proteinopathy: a quantitative study using polynomial curve fitting

AIMS

Previous data suggest heterogeneity in laminar distribution of the pathology in the molecular disorder frontotemporal lobar degeneration (FTLD) with transactive response (TAR) DNA-binding protein of 43 kDa (TDP-43) proteinopathy (FTLD-TDP). To study this heterogeneity, we quantified the changes in density across the cortical laminae of neuronal cytoplasmic inclusions, glial inclusions, neuronal intranuclear inclusions, dystrophic neurites, surviving neurones, abnormally enlarged neurones, and vacuoles in regions of the frontal and temporal lobe.

METHODS

Changes in density of histological features across cortical gyri were studied in 10 sporadic cases of FTLD-TDP using quantitative methods and polynomial curve fitting.

RESULTS

Our data suggest that laminar neuropathology in sporadic FTLD-TDP is highly variable. Most commonly, neuronal cytoplasmic inclusions, dystrophic neurites and vacuolation were abundant in the upper laminae and glial inclusions, neuronal intranuclear inclusions, abnormally enlarged neurones, and glial cell nuclei in the lower laminae. TDP-43-immunoreactive inclusions affected more of the cortical profile in longer duration cases; their distribution varied with disease subtype, but was unrelated to Braak tangle score. Different TDP-43-immunoreactive inclusions were not spatially correlated.

CONCLUSIONS

Laminar distribution of pathological features in 10 sporadic cases of FTLD-TDP is heterogeneous and may be accounted for, in part, by disease subtype and disease duration. In addition, the feedforward and feedback cortico-cortical connections may be compromised in FTLD-TDP.

1p/19q testing has no significance in the workup of glioblastomas

AIMS

To determine whether testing for isolated 1p or 19q losses, or as a codeletion, has any significance in the workup of glioblastomas (GBMs).

METHODS

Upfront 1p/19q testing by fluorescence in situ hybridization (FISH) and/or polymerase chain reaction (PCR)-based loss of heterozygosity (LOH) was done in 491 gliomas that were histologically diagnosed as GBMs. Outcomes were determined and measured against 1p/19q results.

RESULTS

Twenty-eight showed apparent 1p/19q codeletion by either FISH and/or PCR-based LOH, but only 1/26 showed codeletion by both tests. Over 90% of tumours with apparent codeletion by either FISH or LOH also had 10q LOH and/or EGFR amplification, features inversely related to true whole-arm 1p/19q codeletion. Furthermore, only 1/28 tumours demonstrated an R132H IDH1 mutation. Neither 1p/19q codeletion by FISH nor LOH had an impact on GBM survival. Isolated losses of 1p or 19q also had no impact on survival.

CONCLUSIONS

These data suggest that (i) 1p/19q testing is not useful on gliomas that are histologically GBMs; (ii) codeletion testing should be reserved only for cases with compatible morphology; and (iii) EGFR, 10q, and IDH1 testing can help act as safeguards against a false-positive 1p/19q result.

Human and mouse embryonic development, metabolism and gene expression are altered by an ammonium gradient in vitro

Ammonium is generated in culture media by the spontaneous deamination of amino acids at 37 °C and through the metabolism of amino acids by human embryos. The appearance of ammonium is a time-dependent phenomenon and can compromise embryo physiology, development and viability. In this study, the effects of a gradient of ammonium on the development, metabolism and transcriptome of human and mouse embryos were investigated. Pronucleate oocytes were cultured in the presence of an ammonium gradient that mimicked the spontaneous deamination of Eagle's amino acids together with 1 mM glutamine. All embryos were cultured in sequential media G1/G2 at 5% O2, 6% CO2 and 89% N2. Human embryo metabolism was assessed through a non-invasive fluorometric analysis of pyruvate consumption. Transcriptome analysis was performed on the resultant blastocysts from both species using a microarray technology. Embryo development prior to compaction was negatively affected by the presence of low levels of ammonium in both species. Human embryo metabolism was significantly inhibited after just 24 and 48 h of culture. Transcriptome analysis of blastocysts from both species revealed significantly altered gene expression profiles, both decreased and increased. Functional annotation of the altered genes revealed the following over represented biological processes: metabolism, cell growth and/or maintenance, transcription, cell communication, transport, development and transcription regulation. These data emphasize the enhanced sensitivity of the cleavage-stage embryo to its environment and highlight the requirement to renew culture media at frequent intervals in order to alleviate the in vitro induced effects of ammonium build-up in the environment surrounding the embryo.

Should follow-up biopsies for men on active surveillance for prostate cancer be restricted to limited templates?

OBJECTIVE

To investigate if prostate biopsy templates with fewer cores can be used during active surveillance (AS) for prostate cancer.

METHODS

At present, we use an AS protocol template (ASPT) consisting of 13-17 cores. We hypothesize in the setting of known cancer, sextant (6 cores) or standard extended (10-12 cores) templates, could be used with similar effect. We identified patients in our referral institution database (1997-2009) with entry prostate-specific antigen <10 ng/mL, stage ≤cT2, Gleason sum ≤6, ≤3 cores positive for cancer, <50% of single core involved, and age ≤75 years (N = 272). Patients fulfilling standard criteria for pathologic reclassification (N = 94) at any follow-up biopsy were selected for evaluation. By mapping tumor location on the pathologic reclassification determining biopsy, hypothetical scenarios of sextant or standard extended templates (SET) were compared with our ASPT and examined for frequency of cancer detection and pathologic reclassification.

RESULTS

For the 94 patients analyzed, the median number of cores taken was 9.7 (6-22) at baseline and 15 (14-17) for the reclassification biopsy. The median time between baseline and the pathologic reclassification determining biopsy was 15.4 months. Analysis of subgroupings showed that sextant template would identify 84% of cancers and 47.9% of the reclassification events, whereas SET detected 99% of cancers and 81.9% of patients who pathologically reclassified. When only considering Gleason sum ≥7 related progression events, SET found 16.2% less (n = 57) compared with ASPT (n = 68).

CONCLUSION

When monitoring patients on AS, a 13-17 core template detects more pathologic reclassification than standard sextant (18.1%) or extended (52.1%) biopsy templates.

Proof of concept evaluation of the electroencephalophone as a discriminator between wakefulness and general anaesthesia

BACKGROUND

Depth of anaesthesia (DOA) monitors based on the electroencephalogram (EEG) are commonly used in anaesthetic practice. Their technology relies on mathematical analysis of the EEG waveform, generally resulting in a number which corresponds to anaesthetic depth. We have created a novel method of interpreting the EEG, which retains its underlying complexity. This method consists of turning the EEG into a sound: the electroencephalophone (EEP).

METHODS

In a pilot study, we recorded awake and anaesthetized EEGs from six patients. We transformed each EEG into an audio signal using a ring buffer with a write frequency of 1 kHz and a read frequency of 48 kHz, thus elevating all output frequencies by a factor of 48. In essence, the listener hears the previous 12 s of EEG data compressed into 250 ms, updated every 250 ms. From these data, we generated a bank of 5 s audio clips, which were then used to train and test a sample of 23 anaesthetists.

RESULTS

After training, 21 of the 23 anaesthetists were able to use the EEP to correctly identify the conscious state of >5 of 10 randomly selected patients (P<0.001). The median score was 8 out of 10, with an inter-quartile range of 7-9.

CONCLUSIONS

The EEP shows promise as a DOA monitor. However, extensive validation would be required in a variety of clinical settings before it could be accepted into mainstream clinical practice.

Attitudes of mental health staff to protected therapeutic time in adult psychiatric wards

Therapeutic time is a relatively new, ward-based intervention whereby psychiatric nurses spend regular, uninterrupted periods of time with patients during which they do not attend to other matters. A questionnaire survey of nursing and medical staff was conducted to assess attitudes to the approach. The majority of staff viewed the approach as being important for promoting patient recovery, reducing risk, improving nurse-patient relationships and enhancing patient satisfaction with care received. Interference with medical activities, lack of staffing resources and variable patient uptake were highlighted as potential problems. More research is required to establish the benefits, drawbacks and nature of therapeutic time. Given the current support for the approach and previous research emphasizing the extent to which patients value protected time to speak to nurses, investment of resources in further exploration and implementation of this approach may lead to significant clinical returns.