Literature search from ms 29/4/2010

Bourdeaut, F., D. Trochet, et al. (2005). "Germline mutations of the paired-like homeobox 2B (PHOX2B) gene in neuroblastoma." CANCER LETTERS 228(1-2): 51-8.

Hereditary predisposition to neuroblastoma accounts for less than 5% of neuroblastomas and is probably heterogeneous. Recently, a predisposition gene has been mapped to 16p12-p13, but has not yet been identified. Occurrence of neuroblastoma in association with congenital central hypoventilation and Hirschsprung's disease suggests that genes, involved in the development of neural-crest-derived cells, may be altered in these conditions. The recent identification of PHOX2B as the major disease-causing gene in congenital central hypoventilation prompted us to test it as a candidate gene in familial neuroblastoma. We report a family with three first-degree relatives with neuroblastic tumours (namely two ganglioneuromas and one neuroblastoma) in one branch and two siblings with Hirschsprung's disease in another branch. A constitutional R100L PHOX2B mutation was identified in all three patients affected with tumours. We also report a germline PHOX2B mutation in one patient treated for Hirschsprung's disease who subsequently developed a multifocal neuroblastoma in infancy. Both mutations disrupt the homeodomain of the PHOX2B protein. No loss of heterozygosity at the PHOX2B locus was observed in the tumour, suggesting that haplo-insufficiency, gain of function or dominant negative effects may account for the oncogenic effects of these mutations. These observations identify PHOX2B as the first predisposing gene to hereditary neuroblastic tumours. [References: 29]

Bower, R. J. and J. C. Adkins (1980). "Ondine's curse and neurocristopathy." CLINICAL PEDIATRICS 19(10): 665-8.

A newborn with congenital neuroblastomas, Ondine's curse (central hypoventilation) and Hirschsprung's disease is presented. All lesions may be related embryologically and might fall under the general heading of neurocristopathy.

Bowker, S. L., S. L. Pohar, et al. (2006). "A cross-sectional study of health-related quality of life deficits in individuals with comorbid diabetes and cancer." Health & Quality of Life Outcomes 4: 17.

BACKGROUND: Numerous studies have identified a reduced health related quality of life (HRQL) in patients that have either diabetes or cancer. We assessed the HRQL burden in patients with these comorbid conditions, postulating that they would have even greater HRQL deficits. METHODS: Data from the Public Use File of the Canadian Community Health Survey (PUF CCHS) Cycle 1.1 (September 2000-November 2001) were used for this analysis. The total sample size of the CCHS PUF is 130,880 individuals. We used the Health Utilities Index Mark 3 (HUI3) to assess HRQL in patients with: 1) comorbid diabetes and cancer, 2) diabetes alone, 3) cancer alone, and 4) no diabetes or cancer. Analysis of covariance was used to compare the mean overall HUI3 score, controlling for age, sex, marital status, body mass index (BMI), physical activity level, smoking status, education level, depression status, and other chronic conditions. RESULTS: We identified 113,587 individuals (87%) with complete data for the analysis. The comorbid diabetes and cancer group were older and a larger proportion reported being obese, inactive, having less than a secondary education and more chronic conditions when compared to the other three cohorts (p < 0.0001). However, the diabetes and cancer cohort was less likely to be depressed (p < 0.0001). Overall HUI3 scores were significantly lower for the diabetes and cancer group (unadjusted mean (SD): 0.67 (0.30)), compared to diabetes (0.78 (0.27)), cancer (0.78 (0.25)), and the reference group (0.89 (0.18)) (p < 0.0001). After adjusting for covariates, the comorbid diabetes and cancer group continued to have significantly lower overall HUI3 scores than the reference group (unstandardized mean difference: -0.11, 95% CI: -0.13 to -.0.09) (p < 0.0001). CONCLUSION: Individuals with diabetes and cancer had a clinically important and significantly lower HRQL than those with either condition alone. A better understanding of the relationship between diabetes and cancer, and their associated comorbidities, complications, and HRQL deficits may have important implications for prevention and management strategies.

Bradley Judy, M. and M. O'Neill Brenda (2005) Short-term ambulatory oxygen for chronic obstructive pulmonary disease. Cochrane Database of Systematic Reviews Volume, DOI: 10.1002/14651858.CD004356.pub3

BACKGROUND: Ambulatory oxygen is defined as the use of supplemental oxygen during exercise and activities of daily living. Ambulatory oxygen therapy is often used for patients on long term oxygen therapy during exercise, or for non long term oxygen therapy users who achieve some subjective and/or objective benefit from oxygen during exercise. The evidence for the use of ambulatory oxygen therapy is extrapolated from two sources: longer term studies and single assessment studies. Longer term studies assess the impact of ambulatory oxygen therapy used at home during activities of daily living. Single assessment studies compare performance during an exercise test using oxygen with performance during an exercise test using placebo air. OBJECTIVES: To determine the efficacy of ambulatory oxygen in patients with COPD using single assessment studies. SEARCH STRATEGY: The Cochrane Airways Group COPD register was searched with predefined search terms. Searches were current as of March 2005. SELECTION CRITERIA: Only randomised controlled trials were included. Studies did not have to be blinded. Studies had to compare oxygen and placebo when administered to people with COPD who were undergoing an exercise test. DATA COLLECTION AND ANALYSIS: Two reviewers (JB, B'ON) extracted and entered data in to RevMan 4.2. MAIN RESULTS: Thirty one studies (contributing 33 data sets), randomising 534 participants met the inclusion criteria of the review. Oxygen improved all pooled outcomes relating to endurance exercise capacity (distance, time, number of steps) and maximal exercise capacity (exercise time and work rate). Data relating to VO2 max could not be pooled and results from the original studies were not consistent. For the secondary outcomes of breathlessness, SaO2 and VE, comparisons were made at isotime. In all studies except two the isotime is defined as the time at which the placebo test ended. Oxygen improved breathlessness, SaO2/PaO2 and VE at isotime with endurance exercise testing. There was no data on breathlessness at isotime with maximal exercise testing. Oxygen improved SaO2/PaO2 and reduced VE at Isotime. AUTHORS' CONCLUSIONS: This review provides some evidence from small, single assessment studies that ambulatory oxygen improves exercise performance in people with moderate to severe COPD. The results of the review may be affected by publication bias, and the small sample sizes in the studies. Although positive, the findings of the review require replication in larger trials with more distinct subgroups of participants. Maximal or endurance tests can be used in ambulatory oxygen assessment. Consideration should be given to the measurement of SaO2 and breathlessness at isotime as these provide important additional information. We recommend that these outcomes are included in the assessment for ambulatory oxygen. Future research needs to establish the level of benefit of ambulatory oxygen in specific subgroups of people with COPD. SHORT-TERM AMBULATORY OXYGEN FOR CHRONIC OBSTRUCTIVE PULMONARY DISEASE: Short-term studies indicate that people with chronic obstructive pulmonary disease respond to the administration of oxygen when they do exercise tests. Ambulatory oxygen is the use of supplemental oxygen during exercise and activities of daily living. One way to assess if ambulatory oxygen is beneficial for a patient with COPD is to compare the effects of breathing oxygen and breathing air on exercise capacity. Some people with COPD may benefit more than others, and trials should take account of whether people who do not already meet criteria for domiciliary oxygen also respond. This review shows that there is strong evidence that ambulatory oxygen (short-term) improves exercise capacity. Further research needs to focus on which COPD patients benefit from ambulatory oxygen, how much oxygen should be provided and the long-term effect of ambulatory oxygen.
Breslin, F. C. and J. D. Pole (2009). "Work injury risk among young people with learning disabilities and attention-deficit/hyperactivity disorder in Canada." AMERICAN JOURNAL OF PUBLIC HEALTH 99(8): 1423-30.

OBJECTIVES: We sought to gain a better understanding of the relationship between learning disabilities, attention-deficit/hyperactivity disorder (ADHD), and risk of occupational injury among young workers. METHODS: We assessed 15- to 24-year-old workers (n = 14 379) from cycle 2.1 of the Canadian Community Health Survey (CCHS). We gathered data on demographic characteristics, work-related factors, and presence of learning disabilities or ADHD. We conducted a multivariate logistic regression analysis to assess occurrences of medically attended work injuries. RESULTS: There was an 89% adjusted increase in work injury risk among workers with self-reported dyslexia (a type of learning disability) relative to workers reporting no learning disabilities, although this result did not meet traditional statistical significance criteria. Being out of school, either with or without a high school diploma, was associated with a significantly increased risk of work injury, even after control for a number of demographic and work-related variables. CONCLUSIONS: Our findings underscore the notion that individual differences salient in the education system (e.g., learning disabilities, school dropout) need to be integrated into conceptual models of injury risk among young workers.

Brna, P., K. Gordon, et al. (2007). "Health-related quality of life among Canadians with migraine." Journal of Headache & Pain 8(1): 43-8.

The objective was to determine the impact of migraine on health-related quality of life (HRQOL) among Canadians. Analysis was based on the public use microdata set of the Canadian Community Health Survey (CCHS), limited to those aged > or = 15 residing in Manitoba. HRQOL was measured using the SF-36 survey, which covers 8 health concepts. Multivariate linear regression was used to model each SF-36 scale against age, gender, education, income, migraine status and presence of mood or anxiety disorders. Of the 7236 CCHS respondents, 9.7% reported a diagnosis of migraine. Reported migraine predicted statistically significant (p<0.0001) lower HRQOL in all SF-36 domains with profound impairment of physical role, bodily pain and general health. Those reporting a mood disorder scored significantly lower in all domains with pronounced effects on emotional role, social functioning and general health. Reported anxiety disorder was associated with lower HRQOL in 6/8 domains. Canadians with migraine report significant impairment in HRQOL compared to the general population, independent of psychiatric morbidity.

Brna, P., K. Gordon, et al. (2008). "Canadian adolescents with migraine: impaired health-related quality of life." JOURNAL OF CHILD NEUROLOGY 23(1): 39-43.

The objective of this study was to determine the impact of migraine headaches on health-related quality of life among Canadian adolescents. The Canadian Community Health Survey (CCHS) collects information related to health status, health care utilization, and health determinants for the Canadian population. Analysis was limited to those adolescents 12-19 years of age residing in Manitoba. Respondents reported whether they had migraine and mood/anxiety disorders. Health-related quality of life was measured using the Short Form-36 survey, which covers 8 health concepts related to functional status, well-being, and overall health. Multivariate linear regression analysis was used to model each Short Form-36 scale against age (12-14 years vs 15-19 years), gender, migraine, and the presence of a mood or anxiety disorder. The CCHS was completed by 994 respondents; 9.3% (95% confidence interval, 7.3%-11.5%) reported a diagnosis of migraine. Reported migraine predicted both statistically (P < .0001) and clinically significantly lower health-related quality of life in all Short Form-36 domains except vitality and general health perceptions. Adolescents reporting a mood disorder (2.1%) scored significantly lower in 6 of 8 health-related quality of life domains, most pronounced for emotional role, general mental health, and social functioning. Canadian adolescents with migraine report clinically and statistically significant impairment in health-related quality of life compared to their peers, independent of psychiatric comorbidities.

Brosch, M. (1999). "Correlations between neural discharges are related to receptive field properties in cat primary auditory cortex." EUROPEAN JOURNAL OF NEUROSCIENCE 11(10): 3517-3530.

The functional role of correlated neural activity in auditory cortex for the processing of sounds was explored by investigating whether and how cross-correlation parameters are related to receptive field similarities of neurons. Multi-unit activity was recorded simultaneously from several sites of isofrequency domains in primary auditory cortex. At each site various receptive field properties were determined. From the discharges of pairs of clusters, normalized cross-correlation histograms (CCH) were calculated for extended periods of spontaneous activity and for periods with noise-burst stimulation. In both conditions, most CCHs exhibited a symmetrical positivity near the origin of the CCH, a few to several tens of milliseconds wide. Cross-correlation histograms were characterized with two parameters: the correlation strength, which was estimated from the peak correlation, and the correlation width, i.e. the time period of correlated firing, which was measured as the width of the positivity at half height. It was found that correlation strength increased and correlation width narrowed with increasing similarity of the receptive fields of two clusters. These relationships were observed both in the acoustically-driven and spontaneous conditions. Specifically, correlation strength was most strongly associated with similarity in binaural interaction and in temporal response properties such as response onset, response offset and the temporal pattern of the response. Correlation width was predominantly associated with similarity in characteristic frequency, bandwidth and intensity threshold. Results suggest that correlated activity, reflecting potential mechanisms involved in the neural computation in auditory cortex, provides a means to evaluate the properties of the functional organization of auditory cortex. Systematic relationships were found between correlation properties and the receptive field-based organization of cortical processing, suggesting that similar general mechanisms are utilized in many parts of the sensory cortex. In particular, the magnitude and/or the time period of synchronized firing of neurons is increased if the receptive field properties of the involved neurons are similar.

Brouwers, M. J., J. J. Driessen, et al. (2000). "Clinical letter: epidural analgesia in a newborn with Hirschsprung's disease, associated with congenital central hypoventilation syndrome." EUROPEAN JOURNAL OF ANAESTHESIOLOGY 17(12): 751-3.

A case is presented of a neonate with Hirschsprung's disease, associated with congenital central hypoventilation syndrome. After an ileostomy (at 2 days) and a stoma revision (at 10 days), postoperative pain management was established by continuous intravenous infusion of morphine, which caused severe postoperative respiratory depression. At 6 weeks a re-exploration and stoma revision was performed using postoperative epidural analgesia with bupivacaine. This caused no respiratory depression. A colectomy under epidural analgesia at 8 months was also uneventful. Respiratory difficulties in children with congenital central hypoventilation syndrome associated with Hirschsprung's disease are discussed in relation to the technique of choice for postoperative pain management.

Brouwers, M. J. A., J. J. Driessen, et al. (2000). "Epidural analgesia in a newborn with Hirschsprung's disease, associated with congenital central hypoventilation syndrome." EUROPEAN JOURNAL OF ANAESTHESIOLOGY 17(12): 751-753.

A case is presented of a neonate with Hirschsprung's disease, associated with congenital central hypoventilation syndrome. After an ileostomy (at 2 days) and a stoma revision (at 10 days), postoperative pain management was established by continuous intravenous infusion of morphine, which caused severe post-operative respiratory depression. At 6 weeks a reexploration and stoma revision was performed using postoperative epidural analgesia with bupivacaine. This caused no respiratory depression. A colectomy under epidural analgesia at 8 months was also uneventful. Respiratory difficulties in children with congenital central hypoventilation syndrome associated with Hirschsprung's disease are discussed in relation to the technique of choice for postoperative pain management.

Brunet, J.-F. and A. Pattyn (2002). "Phox2 genes - from patterning to connectivity." Current Opinion in Genetics & Development 12(4): 435-40.

In the developing brain, many transcription factors are expressed in complex patterns and dynamics, and drive the differentiation of many classes of neurons. How does the spatio-temporal landscape of transcription factor expression map onto the bewildering variety of neuronal types, and, for each of them, the variety of developmental stages they go through? In other words, what is the logic in the transcriptional control of neuronal differentiation? Here, we review what recent work on the two neuronal-type-specific transcription factors Phox2a and Phox2b has contributed to our understanding of this broad question. [References: 53]

Bucci, M. P., Z. Kapoula, et al. (2003). "Saccades, vergence and combined eye movements in a young subject with Congenital Central Hypoventilation Syndrome (CCHS)." Strabismus 11(2): 95-107.

PURPOSE: To study saccades, vergence and combined eye movements in a case of Congenital Central Hypoventilation Syndrome. METHODS: A 16-year-old girl with congenital partial third cranial nerve palsy, with ptosis and divergent strabismus dependent on viewing distance, participated in this study. A first operation for her ptosis was done seven years ago and an operation for her strabismus was done four years ago. The day of our oculomotor test, the patient had a residual exotropia of 12 prism diopters, mild amblyopia of the left eye and no binocular vision. LEDs on a table placed at eye level were used to stimulate saccades, pure vergence along the median plane and combined saccade-vergence movements. Horizontal eye movements from both eyes were recorded simultaneously with a photoelectric device (Bouis Oculometer). RESULTS: The binocular coordination of saccades in this subject was unstable and more variable than normal, and there was divergent post-saccadic drift, i.e., in the direction of her residual deviation. The patient had difficulty making movements in space, particularly vergence eye movements. Pure saccades and combined movements showed abnormally long latencies and marked hypometrias. The velocity of pure saccades was normal. In contrast, the velocity of saccades in the combined movements was abnormally slow. CONCLUSION: The long latency and the low accuracy of the eye movements in natural space indicate a general deficit in the central circuitry that controls the initiation and programming of all these types of eye movements. The absence of pure vergence and the slowness of the saccades in the combined movements could be due to a brainstem deficit specific to the vergence oculomotor system.

Buch, H., T. Vinding, et al. (2004). "Prevalence and causes of visual impairment and blindness among 9980 Scandinavian adults: the Copenhagen City Eye Study." OPHTHALMOLOGY 111(1): 53-61.

PURPOSE: To investigate the age-specific prevalence and causes of visual impairment and blindness in an epidemiologic study of an adult Scandinavian population. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: The study population was composed of 9980 persons, ages 20 to 84, from the general population of Copenhagen, Denmark. METHODS: This study is based on the third Copenhagen City Heart Study (CCHS III). Participants who reported visual impairment or blindness or had difficulty reading newspaper type and used prescribed eye medications were contacted from 1999 through 2000 and asked to complete a standardized interview concerning their ophthalmologic history. Verification of objective ophthalmologic data was done with a validated questionnaire response method. MAIN OUTCOME MEASURES: Best-corrected visual acuity in the better eye and primary causes of visual impairment and blindness. Visual impairment was defined as visual acuity worse than 20/40 but better than 20/200, and blindness was defined as visual acuity of 20/200 or worse. RESULTS: The age-standardized prevalence rates of visual impairment and blindness were 0.66% and 0.20%, respectively, and rose significantly with age (P<0.001). For persons 20 to 64 years, myopia-related retinal disorders, diabetic retinopathy, optic neuropathy, and retinitis pigmentosa were the most common causes of impaired vision. For persons 65 to 84 years, cataract was the most common cause of visual impairment, whereas age-related macular degeneration was the major cause of blindness. CONCLUSIONS: Visual impairment and blindness are strongly associated with increasing age, and the causes are determined by age. Among persons aged 20 to 64 years, an intervention for the predominating eye diseases might have some effect. Among those aged 65 to 84 years, cataract surgery could reduce visual impairment by one third.

Bullemer, F., S. Heindl, et al. (1999). "["Ondine's curse" in adults]." PNEUMOLOGIE 53 Suppl 2: S91-2.

The term "Ondine's curse" is normally used for congenital central hypoventilation in children. We report on 10 adult patients with this disorder (average age 46 y), who were treated from 1990 to 1996. They were hypercapnic while awake (mean 57 Torr) and during sleep (mean 87 Torr). The CO2-rebreathing response was negative. During exercise test minute ventilation volume did not rise adequately (mean pCO2 : 63 Torr, mean pH: 7.21). Five of these patients underwent emergency intubation before diagnosis, 2 presented with hypoventilation syndrome and 2 with decompensated cor pulmonale, 1 was diagnosed without complaints. 8 patients needed intermittent positive pressure ventilation therapy, 7 of them noninvasive, 1 via tracheal canula. One female patient has already died, the others are under stable clinical condition with the underlying central disorder remaining unchanged. Only 2 patients showed central defects visible in magnetic resonance tomography.

Bulloch, A. G. M. and S. B. Patten (2010). "Non-adherence with psychotropic medications in the general population." Social Psychiatry & Psychiatric Epidemiology 45(1): 47-56.

BACKGROUND: Non-adherence with medications is a general medical issue that has received much attention. However, the majority of studies have been on various clinical populations and the relevance of their results to the general population is unknown. In this study, we sought to determine the degree of non-adherence with antidepressants, antipsychotics, anxiolytics, mood stabilizers and sedative hypnotics, and to determine the reasons for non-adherence, in the general population of Canada. METHODS: We used data from the Canadian Community Health Survey: Mental Health and Well-Being (CCHS 1.2), conducted in 2002 (n = 36,984 adults), to produce population-based estimates of the degree of reported non-adherence with psychotropic medications and the reasons for non-adherence. RESULTS: The number of individuals taking psychotropic medications was 6,201. The prevalence of antipsychotic use over the last 12 months was estimated at 0.4% (95% CI 0.3-0.4). The corresponding estimates for sedative-hypnotics, anxiolytics, mood stabilizers and antidepressants were 10.2% (95% CI 9.8-10.7), 5.5% (95% CI 5.2-5.8), 1.1% (1.0-1.3) and 5.8% (95% CI 5.5-6.2), respectively. Non-adherence was estimated to be 34.6% (95% CI 25.5-44.9) for antipsychotics, 34.7% (95% CI 32.2-37.4) for sedative-hypnotics, 38.1% (95% CI 35.0-41.4) for anxiolytics, 44.9% (95% CI 38.1-51.9) for mood stabilizers and 45.9% (95% CI 43.1-48.7) for antidepressants. The degree of non-adherence decreased with age for antidepressants and anxiolytics. Forgetting was the main reported reason for non-adherence, but its degree varied with medication class. The proportion of respondents that reported forgetting as a reason was 36.3% (95% CI 32.0-40.8) for sedative-hypnotics, 46.7% (95% CI 41.3-52.2) for anxiolytics, 72.7% (95% CI 55.5-85.0) for antipsychotics, 74.2% (95% CI 64.0-82.3) for mood stabilizers and 74.5% (95% CI 70.7-77.9) for antidepressants. The degree of non-adherence and the frequency of forgetting were not associated with the level of interference by the associated condition with usual activities. The majority of these estimates were also not impacted by educational status, employment status, rural/urban residence, income or the presence of a comorbid physical condition. CONCLUSION: A high frequency of non-adherence was found with all five classes of psychotropic medication. Both the frequency of reported non-adherence and the reasons reported for it differ according to the medication. However, the degree of non-adherence was not affected by the level of interference of the associated condition.