Literature search from ms 29/4/2010

Wang, J., S. B. Patten, et al. (2005). "Help-seeking behaviours of individuals with mood disorders." Canadian Journal of Psychiatry - Revue Canadienne de Psychiatrie 50(10): 652-9.

OBJECTIVES: This study had the following objectives: 1) to estimate the 12-month prevalence of conventional and unconventional mental health service use by individuals with major depressive disorder (MDD) or mania in the past year, and 2) to identify factors associated with the use of conventional mental health services by individuals with MDD or mania in the past year. METHODS: We examined data from the Canadian Community Health Survey: Mental Health and Well-Being (CCHS 1.2). Respondents with MDD (n = 1563) or manic episodes (n = 393) in the past 12 months were included in this analysis. RESULTS: An estimated 63.9% of respondents with MDD and 59.0% of those with manic episodes reported having used some type of help in the past 12 months; 52.9% of those with MDD and 49.0% of those with manic episodes used conventional mental health services. Approximately 21% of respondents with either MDD or manic episodes used natural health products specifically for emotional, mental health, and drug or alcohol use problems. Respondents who reported comorbid anxiety disorders and long-term medical conditions were more likely to have used conventional mental health services. CONCLUSIONS: Relative to previous Canadian literature, our analysis suggests that the frequency of conventional mental health service use among persons with MDD has not increased significantly in the past decade. Further, the rate of conventional mental health service use by persons with manic episodes is unexpectedly low. These findings may reflect the lack of national initiatives targeting mood disorders in Canada. They have important implications for planning future education, promotion, and research efforts.

Wang, J. L. (2006). "Perceived work stress, imbalance between work and family/personal lives, and mental disorders." Social Psychiatry & Psychiatric Epidemiology 41(7): 541-8.

BACKGROUND: Occupational mental health research has been focusing on the relationship between work stress and depression. However, the impacts of work stress on anxiety disorders and of imbalance between work and family life on workers' mental health have not been well studied. This analysis investigated the association between levels of perceived work stress and of imbalance between work and family/personal lives and current mood/anxiety disorders. METHOD: This was a cross-sectional study using data from the Canadian Community Health Survey-Mental Health and Well-being (CCHS-1.2) (n=36,984). Mood and anxiety disorders were measured using the World Mental Health-Composite International Diagnostic Interview. RESULTS: The 1-month prevalence of mood and anxiety disorders among those with a work stress score at the 75th percentile value and above was 3.6% and 4.0%. Among those who reported that their work and family/personal lives "never" balanced in the past month, the 1-month prevalence of mood and anxiety disorders was 21.2% and 17.9%. In multivariate analyses, work stress and imbalance between work and family/personal lives were independently associated with mood and anxiety disorders. There was no evidence that perceived work stress interacted with imbalance between work and family/personal lives to increase the likelihood of having mental disorders. Gender was associated with anxiety disorders, but not with major depressive disorder and mood disorders. CONCLUSIONS: Work stress and imbalance between work and family/personal lives may be part of the etiology of mood and anxiety disorders in the working population. Community based longitudinal studies are needed to delineate the causal relationships among work stress, imbalance between work and family/personal lives and mental disorders.

Wang, Y., K. Saigoh, et al. (2000). "YAC/BAC-based physical and transcript mapping around the gracile axonal dystrophy (gad) locus identifies Uchl1, Pmx2b, Atp3a2, and Hip2 genes." GENOMICS 66(3): 333-6.

We generated a yeast artificial chromosome (YAC)/bacterial artificial chromosome (BAC)-based physical and transcript map of a region containing the gracile axonal dystrophy (gad) locus on mouse chromosome 5. The YAC/BAC contig consists of 13 YAC and 49 BAC clones onto which 4 genes, 40 expressed sequence tags, and 7 new DNA polymorphisms were ordered. Using this physical map, we mapped Uchl1 encoding ubiquitin carboxyl-terminal hydrolase I, whose deletion has been determined to cause the gad mutation. We also mapped three other recently identified genes: Hip2, encoding Huntingtin interacting protein 2; Atp3a2, encoding a P-type ATPase; and Pmx2b, encoding PHOX2b. Copyright 2000 Academic Press.

Warnecke, M., H. Oster, et al. (2005). "Abnormal development of the locus coeruleus in Ear2(Nr2f6)-deficient mice impairs the functionality of the forebrain clock and affects nociception." GENES AND DEVELOPMENT 19(5): 614-625.

The orphan nuclear receptor Ear2 (Nr2f6) is transiently expressed in the rostral part of the rhombic lip in which the locus coeruleus (LC) arises. LC development, regulated by a signaling cascade (Mash1 [right arrow] Phox2b [right arrow] Phox2a), is disrupted in Ear2^-/- embryos as revealed by an approximately threefold reduction in the number of Phox2a- and Phox2b-expressing LC progenitor cells. Mash1 expression in the rhombic lip, however, is unaffected, placing Ear2 in between Mash1 and Phox2a/b. Dopamine-beta- hydroxylase and tyrosine hydroxylase staining demonstrate that <70% of LC neurons are absent in the adult with agenesis affecting primarily the dorsal division of the LC. Normally, this division projects noradrenergic efferents to the cortex that appear to be diminished in Ear2^-/- since the cortical concentration of noradrenaline is four times lower in these mice. The rostral region of the cortex is known to contain a circadian pacemaker regulating adaptability to light- and restricted food-driven entrainment. In situ hybridization establishes that the circadian expression pattern of the clock gene Period1 is abolished in the Ear2^-/- forebrain. Behavioral experiments reveal that Ear2 mutants have a delayed entrainment to shifted light-dark cycles and adapt less efficiently to daytime feeding schedules. We propose that neurons in the dorsal division of LC contribute to the regulation of the forebrain clock, at least in part, through targeted release of noradrenaline into the cortical area. copyright 2005 by Cold Spring Harbor Laboratory Press.

Wassermann, K. (2003). "Undine's error. [German]." Atemwegs- und Lungenkrankheiten 29(3): 93-97.

Weese-Mayer, D. E. and E. M. Berry-Kravis (2004). "Genetics of congenital central hypoventilation syndrome: lessons from a seemingly orphan disease." AMERICAN JOURNAL OF RESPIRATORY & CRITICAL CARE MEDICINE 170(1): 16-21.

Weese-Mayer, D. E., E. M. Berry-Kravis, et al. (2010). "An official ATS clinical policy statement: Congenital central hypoventilation syndrome: genetic basis, diagnosis, and management." AMERICAN JOURNAL OF RESPIRATORY & CRITICAL CARE MEDICINE 181(6): 626-44.

BACKGROUND: Congenital central hypoventilation syndrome (CCHS) is characterized by alveolar hypoventilation and autonomic dysregulation. PURPOSE: (1) To demonstrate the importance of PHOX2B testing in diagnosing and treating patients with CCHS, (2) to summarize recent advances in understanding how mutations in the PHOX2B gene lead to the CCHS phenotype, and (3) to provide an update on recommendations for diagnosis and treatment of patients with CCHS. METHODS: Committee members were invited on the basis of their expertise in CCHS and asked to review the current state of the science by independently completing literature searches. Consensus on recommendations was reached by agreement among members of the Committee. RESULTS: A review of pertinent literature allowed for the development of a document that summarizes recent advances in understanding CCHS and expert interpretation of the evidence for management of affected patients. CONCLUSIONS: A PHOX2B mutation is required to confirm the diagnosis of CCHS. Knowledge of the specific PHOX2B mutation aids in anticipating the CCHS phenotype severity. Parents of patients with CCHS should be tested for PHOX2B mutations. Maintaining a high index of suspicion in cases of unexplained alveolar hypoventilation will likely identify a higher incidence of milder cases of CCHS. Recommended management options aimed toward maximizing safety and optimizing neurocognitive outcome include: (1) biannual then annual in-hospital comprehensive evaluation with (i) physiologic studies during awake and asleep states to assess ventilatory needs during varying levels of activity and concentration, in all stages of sleep, with spontaneous breathing, and with artificial ventilation, and to assess ventilatory responsiveness to physiologic challenges while awake and asleep, (ii) 72-hour Holter monitoring, (iii) echocardiogram, (iv) evaluation of ANS dysregulation across all organ systems affected by the ANS, and (v) formal neurocognitive assessment; (2) barium enema or manometry and/or full thickness rectal biopsy for patients with a history of constipation; and (3) imaging for neural crest tumors in individuals at greatest risk based on PHOX2B mutation.

Weese-Mayer, D. E., E. M. Berry-Kravis, et al. (2008). "Congenital central hypoventilation syndrome (CCHS) and sudden infant death syndrome (SIDS): kindred disorders of autonomic regulation." Respiratory Physiology & Neurobiology 164(1-2): 38-48.

Congenital central hypoventilation syndrome (CCHS) and sudden infant death syndrome (SIDS) were long considered rare disorders of respiratory control and more recently have been highlighted as part of a growing spectrum of disorders within the rubric of autonomic nervous system (ANS) dysregulation (ANSD). CCHS typically presents in the newborn period with a phenotype including alveolar hypoventilation, symptoms of ANSD and, in a subset of cases, Hirschsprung disease and later tumors of neural crest origin. Study of genes related to autonomic dysregulation and the embryologic origin of the neural crest led to the discovery of PHOX2B as the disease-defining gene for CCHS. Like CCHS, SIDS is thought to result from central deficits in control of breathing and ANSD, although SIDS risk is most likely defined by complex multifactorial genetic and environmental interactions. Some early genetic and neuropathological evidence is emerging to implicate serotonin systems in SIDS risk. The purpose of this article is to review the current understanding of the genetic basis for CCHS and SIDS, and discuss the impact of this information on clinical practice and future research directions. [References: 142]

Weese-Mayer, D. E., E. M. Berry-Kravis, et al. (2005). "In pursuit (and discovery) of a genetic basis for congenital central hypoventilation syndrome." Respiratory Physiology & Neurobiology 149(1-3): 73-82.

Congenital central hypoventilation syndrome (CCHS) typically presents in the newborn period with a phenotype including alveolar hypoventilation, symptoms of autonomic nervous system dysregulation, and in a subset of cases Hirschsprung disease and later tumors of neural crest origin. Study of genes related to the autonomic dysregulation and the embryologic origin of the neural crest has led to identification of the genetic basis for CCHS, the mode of inheritance, and the presence of mosaicism in a subset of parents. Polyalanine expansion mutations in PHOX2B have been identified to be the disease-defining mutation in CCHS, with a small subset of patients having other mutations in PHOX2B. Further, the size of the polyalanine repeat mutation in PHOX2B is correlated with the severity of the phenotype in CCHS, and non-polyalanine repeat mutations appear to, in general, result in CCHS phenotypes at the severe end of the spectrum. These studies highlight the utility of PHOX2B genetic testing for confirmation of the CCHS diagnosis, for prenatal diagnosis, and for identification of previously undiagnosed adults with unexplained hypercarbia or control of breathing deficits. This diagnostic approach may be a consideration for other complex, seemingly undecipherable diseases that affect infants and children. The purpose of this article is to provide a comprehensive review of current research into the genetic basis for CCHS, an explanation for how these studies evolved, recent studies that begin to explain the mechanisms through which mutations in PHOX2B exert their effects, and clinical application of the genetic testing. [References: 72]

Weese-Mayer, D. E., E. M. Berry-Kravis, et al. (2005). "Adult identified with congenital central hypoventilation syndrome--mutation in PHOX2b gene and late-onset CHS." AMERICAN JOURNAL OF RESPIRATORY & CRITICAL CARE MEDICINE 171(1): 88.

Weese-Mayer, D. E., E. M. Berry-Kravis, et al. (2004). "Sudden infant death syndrome: case-control frequency differences at genes pertinent to early autonomic nervous system embryologic development." PEDIATRIC RESEARCH 56(3): 391-5.

We have previously identified polymorphisms in the serotonin transporter gene promoter region and in intron 2 that were more common among sudden infant death syndrome (SIDS) cases compared with control subjects. To elucidate further the genetic profile that might increase an infant's vulnerability to SIDS, we focused on the recognized relationship between autonomic nervous system (ANS) dysregulation and SIDS. We therefore studied genes pertinent to early embryologic development of the ANS, including MASH1, BMP2, PHOX2a, PHOX2b, RET, ECE1, EDN1, TLX3, and EN1 in 92 probands with SIDS and 92 gender- and ethnicity-matched control subjects. Eleven protein-changing rare mutations were identified in 14 of 92 SIDS cases among the PHOX2a, RET, ECE1, TLX3, and EN1 genes. Only 1 of these mutations (TLX3) was identified in 2 of 92 control subjects. Black infants accounted for 10 of these mutations in SIDS cases and 2 control subjects. Four protein-changing common polymorphisms were identified in BMP2, RET, ECE1, and EDN1, but the allele frequency did not differ between SIDS cases and control subjects. However, among SIDS cases, the allele frequency for the BMP2 common polymorphism demonstrated ethnic differences; among control subjects, the allele frequency for the BMP2 and the ECE1 common polymorphisms also demonstrated ethnic differences. These data represent further refinement of the genetic profile that might place an infant at risk for SIDS.
Weese-Mayer, D. E., E. M. Berry-Kravis, et al. (2003). "Idiopathic congenital central hypoventilation syndrome: analysis of genes pertinent to early autonomic nervous system embryologic development and identification of mutations in PHOX2b." AMERICAN JOURNAL OF MEDICAL GENETICS Part A. 123A(3): 267-78.

Idiopathic congenital central hypoventilation syndrome (CCHS) has been linked to autonomic nervous system dysregulation and/or dysfunction (ANSD) since it was first described in 1970. A genetic basis of CCHS has been proposed because of the reports of four families with two affected children, because of mother-child transmission, and because of a recent report of a polyalanine expansion mutation in PHOX2b in a subset of CCHS subjects. We, therefore, studied genes pertinent to early embryologic development of the ANS including mammalian achaete-scute homolog-1 (MASH1), bone morphogenic protein-2 (BMP2), engrailed-1 (EN1), TLX3, endothelin converting enzyme-1 (ECE1), endothelin-1 (EDN1), PHOX2a, and PHOX2b in 67 probands with CCHS, and gender- and ethnicity-matched controls. No disease-defining mutations were identified in MASH1, BMP2, EN1, TLX3, ECE1, EDN1, or PHOX2a. The 65/67 CCHS probands (97%) were found to be heterozygous for the exon 3 polyalanine expansion mutation identified previously in PHOX2b. Further, there was an association between repeat mutation length and severity of the CCHS/ANSD phenotype. Of the two probands who did not carry the expansion mutation, one had a nonsense mutation in exon 3 which truncated the protein and the other had no mutation in PHOX2b but had a previously reported EDN3 frameshift point mutation. The polyalanine expansion mutation was not found in any of 67 matched controls. Of 54 available families (including 97 unaffected parents), whose child carried the PHOX2b mutation, 4 parents demonstrated mosaicism for an expansion mutation identical to that seen in the CCHS cases, suggesting that not all mutations in affected probands with unaffected parents are de novo. We also studied four women with CCHS who were heterozygous for the PHOX2b mutation, each with one child. Three of the four children were also affected and had the same mutation, demonstrating autosomal dominant inheritance of the mutation. Assay of the PHOX2b polyalanine repeat mutation represents a highly sensitive and specific technique for confirming the diagnosis of CCHS. Identification of the CCHS mutation will lead to clarification of the phenotype, allow for prenatal diagnosis for parents of CCHS probands and adults with CCHS in future pregnancies, and potentially direct intervention strategies for the treatment of CCHS. Copyright 2003 Wiley-Liss, Inc.

Weese-Mayer, D. E., S. Bolk, et al. (2002). "Idiopathic congenital central hypoventilation syndrome: evaluation of brain-derived neurotrophic factor genomic DNA sequence variation." AMERICAN JOURNAL OF MEDICAL GENETICS 107(4): 306-10.

Idiopathic congenital central hypoventilation syndrome (CCHS) is an unique disorder of respiratory control, occurring in association with Hirschsprung disease (HSCR), tumors of neural crest origin, and symptoms of autonomic nervous system dysfunction (ANSD). CCHS is thought to be genetic in origin based upon 1) affected sib pairs, 2) genetic analysis, and 3) identification of genetic mutations in both HSCR and CCHS patients. Because these mutations have been found in but a few cases of CCHS, exploration of other candidate genes has continued. Brain-derived neurotrophic factor (BDNF) represents a potential candidate gene to consider because of altered respiratory control in the BDNF knock-out mouse model and localization to the enteric nervous system in human tissue. The objective of this study was to determine the frequency of BDNF mutations among 19 children with CCHS (five with HSCR) compared to 40 unaffected unrelated controls. Using the known genomic DNA sequence for BDNF, polymerase chain reaction (PCR)-amplified genomic DNA was analyzed by standard sequencing methods. A discrete mutation was identified in one of 19 children with isolated CCHS and the unaffected father. Specifically, an isoleucine was substituted for a threonine or serine in the amino acid sequence. Absence of this mutation in 40 controls confirmed that this mutation was likely not a common polymorphism. These data further support a genetic basis for CCHS, though mutations of BDNF are not consistent in this disorder. Copyright 2001 Wiley-Liss, Inc.

Weese-Mayer, D. E., A. S. Morrow, et al. (1989). "Diaphragm pacing in infants and children. A life-table analysis of implanted components." American Review of Respiratory Disease 139(4): 974-9.

Since 1976, we have implanted bilateral phrenic nerve electrodes for diaphragm pacing in 33 infants and children. This population includes 23 patients with congenital central hypoventilation syndrome (CHS), two with late onset CHS and hypothalamic dysfunction, three with hypoventilation associated with Chiari II malformation and myelomeningocele, and five with quadriplegia. Our experience, totalling 192 system-years and 96 patient-years of pacing, has enabled us to document the nature and frequency of problems related to the implanted components of the Avery Laboratories (S-232-1) pacemaker system when used in a pediatric population. By life table analysis, the mean time to need for replacement of any implanted component was 56.3 months. A total of 26 failures requiring component replacement occurred and were classified into four types: (1) receiver failure (15 cases), (2) electrode wire or wire insulation breakage (six cases), (3) infection requiring diaphragm pacer system removal (three cases), and (4) mechanical nerve injury (two cases). We conclude that the present diaphragm pacing system is effective but not without risk of biomedical component failure. The present system might be substantially improved by (1) a modified receiver design with a hermetic seal to prevent fluid penetration, (2) stronger, better insulated electrode wires, and (3) modifications of surgical technique and electrode type to prevent phrenic nerve damage.

Weese-Mayer, D. E., C. M. Rand, et al. (2009). "Congenital central hypoventilation syndrome from past to future: model for translational and transitional autonomic medicine." PEDIATRIC PULMONOLOGY 44(6): 521-35.

The modern story of CCHS began in 1970 with the first description by Mellins et al., came most visibly to the public eye with the ATS Statement in 1999, and continues with increasingly fast paced advances in genetics. Affected individuals have diffuse autonomic nervous system dysregulation (ANSD). The paired-like homeobox gene PHOX2B is the disease-defining gene for CCHS; a mutation in the PHOX2B gene is requisite to the diagnosis of CCHS. Approximately 90% of individuals with the CCHS phenotype will be heterozygous for a polyalanine repeat expansion mutation (PARM); the normal allele will have 20 alanines and the affected allele will have 24-33 alanines (genotypes 20/24-20/33). The remaining approximately 10% of individuals with CCHS will have a non-PARM (NPARM), in the PHOX2B gene; these will be missense, nonsense, or frameshift. CCHS and PHOX2B are inherited in an autosomal dominant manner with a stable mutation. Approximately 8% of parents of a CCHS proband will be mosaic for the PHOX2B mutation. A growing number of cases of CCHS are identified after the newborn period, with presentation from infancy into adulthood. An improved understanding of the molecular basis of the PHOX2B mutations and of the PHOX2B genotype/CCHS phenotype relationship will allow physicians to anticipate the clinical phenotype for each affected individual. To best convey the remarkable history of CCHS, and to describe the value of recognizing CCHS as a model for translational and transitional autonomic medicine, we present this review article in the format of a chronological story, from 1970 to the present day. [References: 104]

Weese-Mayer, D. E., D. C. Shannon, et al. (1999). "Idiopathic congenital central hypoventilation syndrome: Diagnosis and management." AMERICAN JOURNAL OF RESPIRATORY AND CRITICAL CARE MEDICINE 160(1): 368-373.

Weese-Mayer, D. E., J. M. Silvestri, et al. (2001). "Case/control family study of autonomic nervous system dysfunction in idiopathic congenital central hypoventilation syndrome." AMERICAN JOURNAL OF MEDICAL GENETICS 100(3): 237-45.

Children with idiopathic congenital central hypoventilation syndrome (CCHS) have a complex phenotype consistent with an imbalance of the autonomic nervous system (ANS). Since CCHS may be genetic in origin, we hypothesized that relatives of individuals with CCHS may exhibit symptoms of ANS dysfunction (ANSD), albeit in a milder form. We tested this hypothesis by assessing aspects of ANS function in relatives of CCHS cases vs. relatives of matched controls with a scripted questionnaire. Only those 35 symptoms of ANSD exhibited by > or =5% of the CCHS cases were included in the analysis as the basis for determining ANSD affection status. Two different arbitrary ANSD affection status definitions are presented in detail: any case, control, or relative with positive findings (1) in two or more symptoms, or (2) in two or more systems. The subjects included in the analysis totaled 2,353, including 56 CCHS cases, 56 age-, gender-, and race-matched controls, and their families. Under each of the two arbitrary ANSD affection statuses, CCHS cases and parents of cases were more likely to be affected than controls and parents of controls (P < 0.001 for both comparisons), 16% of the CCHS siblings had the ANSD phenotype with two or more symptoms, compared to 4% of control siblings (P = 0.03). Aunts and uncles of the CCHS cases were also significantly more likely to have two or more ANSD symptoms than were aunts and uncles of the controls (P= 0.009). These results support our hypothesis and also indicate that relatives of the CCHS cases tended to manifest a milder spectrum of ANSD, with fewer systems and/or fewer symptoms than the cases. Copyright 2001 Wiley-Liss, Inc.