A threonine to isoleucine missense mutation in the pericentriolar material 1 gene is strongly associated with schizophrenia

Markers at the pericentriolar material 1 gene (PCM1) have shown genetic association with schizophrenia in both a University College London (UCL) and a USA-based case-control sample. In this paper we report a statistically significant replication of the PCM1 association in a large Scottish case-control sample from Aberdeen. Resequencing of the genomic DNA from research volunteers who had inherited haplotypes associated with schizophrenia showed a threonine to isoleucine missense mutation in exon 24 which was likely to change the structure and function of PCM1 (rs370429). This mutation was found only as a heterozygote in 98 schizophrenic research subjects and controls out of 2246 case and control research subjects. Among the 98 carriers of rs370429, 67 were affected with schizophrenia. The same alleles and haplotypes were associated with schizophrenia in both the London and Aberdeen samples. Another potential aetiological base pair change in PCM1 was rs445422, which altered a splice site signal. A further mutation, rs208747, was shown by electrophoretic mobility shift assays to create or destroy a promoter transcription factor site. Five further non-synonymous changes in exons were also found. Genotyping of the new variants discovered in the UCL case-control sample strengthened the evidence for allelic and haplotypic association (P=0.02-0.0002). Given the number and identity of the haplotypes associated with schizophrenia, further aetiological base pair changes must exist within and around the PCM1 gene. PCM1 protein has been shown to interact directly with the disrupted-in-schizophrenia 1 (DISC1) protein, Bardet-Biedl syndrome 4, and Huntingtin-associated protein 1, and is important in neuronal cell growth. In a separate study we found that clozapine but not haloperidol downregulated PCM1 expression in the mouse brain. We hypothesize that mutant PCM1 may be responsible for causing a subtype of schizophrenia through abnormal cell division and abnormal regeneration in dividing cells in the central nervous system. This is supported by our previous finding of orbitofrontal volumetric deficits in PCM1-associated schizophrenia patients as opposed to temporal pole deficits in non-PCM1-associated schizophrenia patients. Caution needs to be exercised in interpreting the actual biological effects of the mutations we have found without further cell biology. However, the DNA changes we have found deserve widespread genotyping in multiple case-control populations.

Factors associated with radiation exposure in patients with inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) patients undergo multiple radiological evaluations.

AIM

To estimate total and abdominal radiation exposure from diagnostic X-ray investigations in IBD patients and the associated risk factors.

METHODS

Patients with Crohn's disease (CD) or ulcerative colitis (UC) treated in the IBD clinic were recruited. Clinical data were extracted from patient files and radiological data were obtained from the central HMO computer data base.

RESULTS

A total of 199 CD and 125 UC patients were included. The mean cumulative estimated doses (CED) for CD and UC were 21.1 19.5 and 15.1 20.4 millisieverts (mSv) respectively (P < 0.001). Twenty-three patients (7.1%) had an estimated CED of > or =50 mSv. In multivariate analyses, predictors of increased CED were: surgery (OR 5.68, 95% CI: 2.73-11.8, P < 0.001), CD (OR 2.56, 95% CI: 1.29-5.07, P = 0.007), prednisone use (OR 2.0, 95% CI: 1.11-3.67, P = 0.02), first year of disease (OR 6.4, 95% CI: 1.3-32, P = 0.02) and age in the upper quartile(OR 3.26, 95% CI: 1.68-6.3, P = 0.001).

CONCLUSIONS

Diagnosis of CD, IBD-related surgery, prednisone use, first year of diagnosis and age on the upper quartile are independent predictors of increased exposure in IBD patients. Alternative investigations which do not require radiation exposure should be considered for patients at risk for increased radiation exposure.

An investigation of medication information transfer and application in aged care facilities in an Australian rural setting

INTRODUCTION

As patients move within Australia's increasingly complex healthcare system, it is desirable that they receive uninterrupted, timely and accurate administration of medication. For this to occur, effective communication of medication information is required, and mechanisms must be in place to ensure timely administration. This study focused on these issues as they apply to patients being admitted to aged care facilities in an Australian rural setting, including investigation of the transfer and early application of information about their current medications (or 'medication information'). Electronic prescribing and associated information transfer may improve the transfer of medication information in the future; however, this study focused on the current situation in rural Australia.

METHOD

In this observational study, patient outcomes and participating nurses' experience of medication issues related to admissions to rural residential aged care facilities from an acute hospital, a rehabilitation facility, another aged care facility or the community were investigated. Data were collected using a customised questionnaire completed by nursing staff at participating aged care facilities.

RESULTS

Data relating to 59 individual patient transfers were obtained from 14 aged care facilities. A number of pathways for the communication of medication information were identified, with timely and effective information transfer occurring for most patients. However, one in five patients experienced a delay of up to 4 hours, and a limited number of incidents of inadequate information transfer were identified. While most patient transfers occurred with 12 or more hours notice, one in ten transfers occurred with no more than one hour of notice. Transfers were not evenly distributed among week days; however, very few transfers occurred after 5 pm on Friday. A number of staff reported that they had felt it necessary to act beyond their normal employee duties to ensure timely medication delivery to their aged care residents.

CONCLUSIONS

This study identified pathways used to transfer medication information about patients being admitted to aged care facilities, and also immediate responses to that information. The study indicates that these processes, while generally satisfactory, are at times less than ideal. Health professionals in rural Australia may be in an ideal position to develop and implement effective local responses to identified problems, by activating interprofessional links. The study also highlights the issue of aged care staff acting outside their designated role in an attempt to ensure timely medication administration to their patients, a potentially inefficient use of limited staff time.

The value of interhospital transfer and emergency MRI for suspected cauda equina syndrome: a 2-year retrospective study

INTRODUCTION

The timing of surgery in cauda equina syndrome due to prolapsed intervertebral disc remains controversial. Assessment of these patients requires magnetic resonance imaging (MRI), which is of limited availability outside normal working hours in the UK.

PATIENTS AND METHODS

We reviewed radiological results in all patients undergoing emergency MRI within our unit for suspected cauda equina syndrome over a 2-year period, and all subjects undergoing emergency lumbar discectomy for cauda equina syndrome within the same period. Outcome measures were: proportion of positive findings in symptomatic patients and proportion of patients referred with diagnostic MRI scans undergoing emergency surgery. We also assessed outcomes of patients having surgery for cauda equina syndrome in terms of improvement of pain, sensory and sphincter disturbance.

RESULTS

A total of 76 patients were transferred for assessment and 'on-call' MRI; 27 were subsequently operated upon. Only 5 proceeded to emergency discectomy that night (prior to next scheduled list). This may be due to delays in timing--from referral to acceptance, to arrival in the department, to diagnostic scan and to theatre. With the second group of patients, 43 had emergency discectomy for cauda equina syndrome during the study period. Of these, 6 patients had an out-of-hours MRI at our hospital for assessment (one patient living locally). Most surgically treated patients experienced improvement in their pain syndrome, with approximately two-thirds experiencing improvement in sensory and sphincter disturbance.

CONCLUSIONS

These data support a policy of advising MRI scan for cauda equina syndrome at the earliest opportunity within the next 24 h in the referring hospital, rather than emergency transfer for diagnostic imaging which has a relatively low yield in terms of patients operated on as an emergency.

Alemtuzumab in chronic lymphocytic leukemia

QUESTIONS

With respect to outcomes such as survival, response rate, response duration, time to progression, and quality of life, is alemtuzumab a beneficial treatment option for patients with B-cell chronic lymphocytic leukemia (cll)?What toxicities are associated with the use of alemtuzumab?Which patients are more likely-or less likely-to benefit from treatment with alemtuzumab?

PERSPECTIVES

Evidence was selected and reviewed by one member of the Hematology Disease Site Group (dsg) of Cancer Care Ontario's Program in Evidence-Based Care (pebc) and by methodologists. The practice guideline report was reviewed and approved by the Hema-tology dsg, which comprises hematologists, medical and radiation oncologists, and a patient representative. As part of an external review process, the report was disseminated to obtain feedback from practitioners in Ontario.

OUTCOMES

Outcomes of interest were overall survival, quality of life, response rates and duration, and adverse event rates.

METHODOLOGY

A systematic review of the medline, embase, HealthStar, cinahl, and Cochrane Library databases was conducted to search for primary articles and practice guidelines. The evidence informed the development of clinical practice recommendations. The evidence review and recommendations were appraised by a sample of practitioners from Ontario, Canada, and were modified in response to the feedback received. The systematic review and modified recommendations were approved by a review body within the pebc.

RESULTS

The literature review found no published randomized controlled trials (rcts) that evaluated alem-tuzumab alone or in combination with other chemotherapeutic agents for the treatment of relapsed or refractory cll. One rct evaluated alemtuzumab administered to consolidate a complete or partial response to first-line fludarabine-containing chemotherapy. That study was stopped early because of excessive grades 3 and 4 infection-related toxicity in the alemtuzumab arm. Patients receiving alemtuzumab experienced significantly improved progression-free survival as compared with patients undergoing observation. Six single-arm studies evaluated disease response with administration of alemtuzumab as a single agent in the treatment of patients with relapsed or refractory cll post-fludarabine. The pooled overall response rate was 38% (complete response: 6%; partial response: 32%). Adverse events associated with the use of alemtuzumab were commonly reported and included serious infusion-related, hematologic, and infection-related toxicities.

RECOMMENDATION

This evidence-based recommendation applies to adult patients with B-cell cll. Treatment with alemtuzumab is a reasonable option for patients with progressive and symptomatic cll that is refractory to both alkylator-based and fludarabine-based regimens.

QUALIFYING STATEMENTS

The evidence supporting treatment with alemtuzumab comes principally from case series that evaluated disease response as the primary outcome measure. Patients should be informed that any possible beneficial effect of alemtuzumab on other outcome measures such as duration of response, quality of life, and overall survival are not supported in evidence and currently remain speculative. Treatment with alemtuzumab is associated with significant and potentially serious treatment-related toxicities. Patients must be carefully informed of the uncertain balance between potential risks of harm and the chance for benefit reported in studies. Given the current substantial uncertainty in this balance, patient preferences will likely play a large role in determining the appropriate treatment choice. Given the potential toxicities associated with alemtuzumab, and given the limited nature of the agent's testing in clinical trials in broad populations of patients with cll, the use of alemtuzumab in patients with important comorbidities may be associated with excessive risks.

Misunderstanding of prostate cancer (CaP) among African American (AA) men of lower socioeconomic status (Lo-SES)

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Background: CaP disproportionately affects AA men. The objective of this investigation was to assess understanding of the prostate and CaP among Lo-SES, predominantly AA men. Methods: We performed cross sectional, semistructured interviews of 105 men, age 40 and older, in two low-income medical clinics. CaP knowledge was assessed using a subset of questions by Mercer et al. Can J of Public Health 88(5):327, 1997. Patients were shown two male anatomic figures and asked to identify the prostate, bladder, bowels, and penis: 1) Please point to the _____ on the picture of the man. 2) What does the ____ do? Patients’ understanding of sexual, urinary, and bowel function was evaluated using semi-qualitative methods coded by two independent investigators. Demographic data were collected and literacy measured using REALM. Results: Patients’ median age was 58 and 87% self-identified their race as AA. Median annual household income was $16,000. Median reading level was 4th-6th grade. Although 87% of patients had heard of the prostate, only 24% could locate the prostate, and 3% could explain prostate function. Because many men learn about the prostate in the context of CaP screening during physical exam, 23% of patients thought the prostate was synonymous with prostate cancer, 15% of patients believed the prostate is located in the rectum and 4% confused prostate cancer with colorectal cancer. Prostate cancer knowledge was poor and the concept of a risk factor was not understood well. Only 7% could name a single risk factor for CaP including 3% who named race. Just 22% of men cited surgery or radiation therapy as treatments for CaP and 11% could name a side effect of early CaP treatment. Domain confusion was common: 43% of patients confused bowel function with urinary function, 21% confused urinary with sexual function, and 20% confused bowel with sexual function. Conclusions: Baseline understanding of CaP, anatomy, bowel, urinary, and sexual function is poor among older, lo-SES AA men. Substantial patient education is required for CaP screening and treatment efforts in this population with consideration for low literacy.

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Nutrient loss and water quality under extensive grazing in the upper Burdekin river catchment, North Queensland

Increased sediment and nutrient losses resulting from unsustainable grazing management in the Burdekin River catchment are major threats to water quality in the Great Barrier Reef Lagoon. To test the effects of grazing management on soil and nutrient loss, five 1 ha mini-catchments were established in 1999 under different grazing strategies on a sedimentary landscape near Charters Towers. Reference samples were also collected from watercourses in the Burdekin catchment during major flow events. Soil and nutrient loss were relatively low across all grazing strategies due to a combination of good cover, low slope and low rainfall intensities. Total soil loss varied from 3 to 20 kg ha(-1) per event while losses of N and P ranged from 10 to 1900 g ha(-1) and from 1 to 71 g ha(-1) per event respectively. Water quality of runoff was considered moderate across all strategies with relatively low levels of total suspended sediment (range: 8-1409 mg l(-1)), total N (range: 101-4000 microg l(-1)) and total P (range: 14-609 microg l(-1)). However, treatment differences are likely to emerge with time as the impacts of the different grazing strategies on land condition become more apparent. Samples collected opportunistically from rivers and creeks during flow events displayed significantly higher levels of total suspended sediment (range: 10-6010 mg l(-1)), total N (range: 650-6350 microg l(-1)) and total P (range: 50-1500 microg l(-1)) than those collected at the grazing trial. These differences can largely be attributed to variation in slope, geology and cover between the grazing trial and different catchments. In particular, watercourses draining hillier, grano-diorite landscapes with low cover had markedly higher sediment and nutrient loads compared to those draining flatter, sedimentary landscapes. These preliminary data suggest that on relatively flat, sedimentary landscapes, extensive cattle grazing is compatible with achieving water quality targets, provided high levels of ground cover are maintained. In contrast, sediment and nutrient loss under grazing on more erodable land types is cause for serious concern. Long-term empirical research and monitoring will be essential to quantify the impacts of changed land management on water quality in the spatially and temporally variable Burdekin River catchment.

Alcohol, tobacco and breast cancer--collaborative reanalysis of individual data from 53 epidemiological studies, including 58,515 women with breast cancer and 95,067 women without the disease

Alcohol and tobacco consumption are closely correlated and published results on their association with breast cancer have not always allowed adequately for confounding between these exposures. Over 80% of the relevant information worldwide on alcohol and tobacco consumption and breast cancer were collated, checked and analysed centrally. Analyses included 58,515 women with invasive breast cancer and 95,067 controls from 53 studies. Relative risks of breast cancer were estimated, after stratifying by study, age, parity and, where appropriate, women's age when their first child was born and consumption of alcohol and tobacco. The average consumption of alcohol reported by controls from developed countries was 6.0 g per day, i.e. about half a unit/drink of alcohol per day, and was greater in ever-smokers than never-smokers, (8.4 g per day and 5.0 g per day, respectively). Compared with women who reported drinking no alcohol, the relative risk of breast cancer was 1.32 (1.19-1.45, P<0.00001) for an intake of 35-44 g per day alcohol, and 1.46 (1.33-1.61, P<0.00001) for >/=45 g per day alcohol. The relative risk of breast cancer increased by 7.1% (95% CI 5.5-8.7%; P<0.00001) for each additional 10 g per day intake of alcohol, i.e. for each extra unit or drink of alcohol consumed on a daily basis. This increase was the same in ever-smokers and never-smokers (7.1% per 10 g per day, P<0.00001, in each group). By contrast, the relationship between smoking and breast cancer was substantially confounded by the effect of alcohol. When analyses were restricted to 22 255 women with breast cancer and 40 832 controls who reported drinking no alcohol, smoking was not associated with breast cancer (compared to never-smokers, relative risk for ever-smokers=1.03, 95% CI 0.98-1.07, and for current smokers=0.99, 0.92-1.05). The results for alcohol and for tobacco did not vary substantially across studies, study designs, or according to 15 personal characteristics of the women; nor were the findings materially confounded by any of these factors. If the observed relationship for alcohol is causal, these results suggest that about 4% of the breast cancers in developed countries are attributable to alcohol. In developing countries, where alcohol consumption among controls averaged only 0.4 g per day, alcohol would have a negligible effect on the incidence of breast cancer. In conclusion, smoking has little or no independent effect on the risk of developing breast cancer; the effect of alcohol on breast cancer needs to be interpreted in the context of its beneficial effects, in moderation, on cardiovascular disease and its harmful effects on cirrhosis and cancers of the mouth, larynx, oesophagus and liver.

Protective effect of faecal occult blood test screening for colorectal cancer: worse prognosis for screening refusers

BACKGROUND AND AIMS

Screening for colorectal cancer (CRC) by faecal occult blood testing (FOBT) decreases CRC mortality by 15-33%. Compliance remains an obstacle to maximising the benefit of FOBT screening. We tested the hypothesis that individuals offered FOBT screening but refused would have an increased incidence and worse prognosis for CRC compared with those tested and with controls.

METHODS

Annual screening was offered to 3548 average risk individuals, > or = 40 years of age, from a highly stable population. A total of 2538 agreed to testing (group 1) and 1010 (28%) refused (group 2). Another 1376 individuals were never offered the test and served as controls (group 3). The groups were followed for 11 years: a three year screening period (1985-1987) and an eight year follow up period at the end of the screening programme (1988-1995). Incidence, stage, and mortality were compared. Characterisation of refusers was completed in 188 and 130 subjects of groups 1 and 2, respectively.

RESULTS

In the screening phase, mortality from CRC was significantly lower in group 1 than in groups 2 and 3. The cumulative incidence of CRC in the eight year follow up period was 21 (0.88%), 23 (2.28%), and 13 (0.94%) in groups 1, 2, and 3, respectively. This shows a reduction of 61.4% in group 1 compared with group 2 (relative risk 0.28 (95% confidence interval (CI) 0.19-0.32)) (p<0.001) and 6.4% compared with group 3 (relative risk 0.93 (95% CI 0.93-1.00)) (NS). During follow up, group 1 subjects also demonstrated a decrease in advanced Dukes' stage and mortality rate by 80% and 64%, and 79% and 62%, compared with groups 2 and 3, respectively. Refusers were more likely to be male, of Asian-African descent, and more likely to smoke, consume more coffee, and less tea or dairy foods.

CONCLUSIONS

When accepted, FOBT may protect against CRC for prolonged periods. Individuals who refuse FOBT have a significantly higher CRC incidence and mortality rates than those who accept testing.

Umbravirus gene expression helps potato leafroll virus to invade mesophyll tissues and to be transmitted mechanically between plants

Potato leafroll virus (PLRV) was mechanically transmissible when inocula also contained the umbravirus Pea enation mosaic virus-2 (PEMV-2). In plants infected with PLRV and PEMV-2, PLRV accumulated in clusters of mesophyll cells in both inoculated and systemically infected leaves. No transmissions were obtained by coinoculation with Potato virus Y, Potato virus X (PVX), Tobacco mosaic virus, or Cucumber mosaic virus (CMV), although PLRV was transmissible from mixtures with CMV(ORF4) (a recombinant that contained the movement protein (MP) gene of the umbravirus Groundnut rosette virus (GRV) in place of the CMV MP gene). In contrast, neither a recombinant PVX that expressed GRV MP nor a mutant of CMV(ORF4), in which the CMV 2b gene was untranslatable, was able to help PLRV transmission. Possibly both a cell-to-cell movement function and counterdefense mechanisms such as those that block posttranscriptional gene silencing are involved in movement of PLRV within plants and its mechanical transmission between plants.