Proteolytic degradation and potential role of onconeural protein cdr2 in neurodegeneration.

Cerebellar degeneration-related protein 2 (cdr2) is expressed in the central nervous system, and its ectopic expression in tumor cells of patients with gynecological malignancies elicits immune responses by cdr2-specific autoantibodies and T lymphocytes, leading to neurological symptoms. However, little is known about the regulation and function of cdr2 in neurodegenerative diseases. Because we found that cdr2 is highly expressed in the midbrain, we investigated the role of cdr2 in experimental models of Parkinson's disease (PD). We found that cdr2 levels were significantly reduced after stereotaxic injection of 1-methyl-4-phenylpyridinium (MPP(+)) into the striatum. cdr2 levels were also decreased in the brains of post-mortem PD patients. Using primary cultures of mesencephalic neurons and MN9D cells, we confirmed that MPP(+) reduces cdr2 in tyrosine hydroxylase-positive dopaminergic neuronal cells. The MPP(+)-induced decrease of cdr2 was primarily caused by calpain- and ubiquitin proteasome system-mediated degradation, and cotreatment with pharmacological inhibitors of these enzymes or overexpression of calcium-binding protein rendered cells less vulnerable to MPP(+)-mediated cytotoxicity. Consequently, overexpression of cdr2 rescued cells from MPP(+)-induced cytotoxicity, whereas knockdown of cdr2 accelerated toxicity. Collectively, our findings provide insights into the novel regulatory mechanism and potentially protective role of onconeural protein during dopaminergic neurodegeneration.

Racial/ethnic and Weight Status Differences in Food Preparation among WIC Participants.

The main purpose of this study was to examine whether the Supplemental Nutrition Program for Women, Infants and Children (WIC) helped mothers of overweight/obese preschool children to cut down on dietary fat and sugar intake for their families. Data from the Children Eating Well for Health (CHEW) Nutrition Survey, a probability sample of 150 (50 each White, Black and Hispanic) families with preschoolers participating in the WIC program in Nashville/Davidson County, Tennessee, were analyzed using logistic regression modeling. Mothers who reported that the WIC program helped them reduce fat intake were 2.5 times more likely to have an overweight/obese child and 2.1 times more likely to be obese themselves. No significant effects were found for adding sugar. These results suggest that the mothers in this sample were applying WIC nutritional counseling to use food preparation techniques that cut down on added fats for themselves and their children who were at risk due to weight status.

Short communication: a food-systems approach to assessing dairy product waste.

Concern about world population increase, food security, and the environmental burdens of food production have made food-waste reduction a social and environmental priority. In this context, the quantification of dairy product waste is especially difficult due to the varied means of disposal, by solid and liquid waste streams, and due to inclusion as an ingredient in many processed foods. In this study, food intake data from the Australian National Nutrition Survey (>13,000 participants; >4,500 food items) were disaggregated into basic foods and total national dairy product intake was expressed in whole-milk equivalents. This result was compared with total domestic milk supply, indicating a level of waste of 29% for dairy products in the Australian food system. With national food-waste reduction targets becoming increasingly common, reliable estimates of food waste at the national scale are important for goal setting, baseline reporting, and performance monitoring. For this purpose, the systems approach to assessing food waste demonstrated in this project is deemed to have advantages over other common methods of food-waste assessment, such as bin audits, waste diaries, and surveys.

Fatty infiltrate in the cervical extensor muscles is not a feature of chronic, insidious-onset neck pain.

AIM: To investigate the presence of fatty infiltrate in the cervical extensor musculature in patients with insidious-onset neck pain to better understand the possible pathophysiology underlying such changes in chronic whiplash-associated disorders (WAD). MATERIALS AND METHODS: A sample of convenience of 23 women with persistent insidious-onset neck pain (mean age 29.2+/-6.9 years) was recruited for the study. Magnetic resonance imaging (MRI) was used to quantify fatty infiltration in the cervical extensor musculature. Quantitative Sensory Testing (QST; pressure and thermal pain thresholds) was performed as sensory features are present in chronic whiplash. Self-reported pain and disability, as well as psychological distress, were measured using the Neck Disability Index (NDI) and the General Health Questionnaire-28 (GHQ-28), respectively. RESULTS: Measures were compared with those of a previous dataset of chronic whiplash patients (n=79, mean age 29.7+/-7.8 years). Using a classification tree, insidious-onset neck pain was clearly identified from whiplash (p<0.001), based on the presence of MRI fatty infiltrate in the cervical extensor musculature (0/102 individuals) and altered temperature thresholds (cold; 3/102 individuals). CONCLUSION: Fatty infiltrates in the cervical extensor musculature and widespread hyperalgesia were not features of the insidious-onset neck pain group in this study; whereas these features have been identified in patients with chronic WAD. This novel finding may enable a better understanding of the underlying pathophysiological processes in patients with chronic whiplash.

Alterations in cervical muscle activity in functional and stressful tasks in female office workers with neck pain.

This study determined differences between computer workers with varying levels of neck pain in terms of work stressors, employee strain, electromyography (EMG) amplitude and heart rate response to various tasks. Participants included 85 workers (33, no pain; 38, mild pain; 14, moderate pain) and 22 non-working controls. Work stressors evaluated were job demands, decision authority, and social support. Heart rate was recorded during three tasks: copy-typing, typing with superimposed stress and a colour word task. Measures included electromyography signals from the sternocleidomastoid (SCM), anterior scalene (AS), cervical extensor (CE) and upper trapezius (UT) muscles bilaterally. Results showed no difference between groups in work stressors or employee strain measures. Workers with and without pain had higher measured levels of EMG amplitude in SCM, AS and CE muscles during the tasks than controls (all P < 0.02). In workers with neck pain, the UT had difficulty in switching off on completion of tasks compared with controls and workers without pain. There was an increase in heart rate, perceived tension and pain and decrease in accuracy for all groups during the stressful tasks with symptomatic workers producing more typing errors than controls and workers without pain. These findings suggest an altered muscle recruitment pattern in the neck flexor and extensor muscles. Whether this is a consequence or source of the musculoskeletal disorder cannot be determined from this study. It is possible that workers currently without symptoms may be at risk of developing a musculoskeletal disorder.

Cervical musculoskeletal impairment in frequent intermittent headache. Part 2: subjects with concurrent headache types.

A pattern of musculoskeletal impairment inclusive of upper cervical joint dysfunction, combined with restricted cervical motion and impairment in muscle function, has been shown to differentiate cervicogenic headache from migraine and tension-type headache when reported as single headaches. It was questioned whether this pattern of cervical musculoskeletal impairment could discriminate a cervicogenic headache as one type of headache in more complex situations when persons report two or more headaches. Subjects with two or more concurrent frequent intermittent headache types (n = 108) and 57 non-headache control subjects were assessed using a set of physical measures for the cervical musculoskeletal system. Discriminant and cluster analyses revealed that 36 subjects had the pattern of musculoskeletal impairment consistent with cervicogenic headache. Isolated features of physical impairment, e.g. range of movement (cervical extension), were not helpful in differentiating cervicogenic headache. There were no differences in measures of cervical musculoskeletal impairment undertaken in this study between control subjects and those classified with non-cervicogenic headaches.

Cervical musculoskeletal impairment in frequent intermittent headache. Part 1: Subjects with single headaches.

Musculoskeletal disorders are considered the underlying cause of cervicogenic headache, but neck pain is commonly associated with migraine and tension-type headaches. This study tested musculoskeletal function in these headache types. From a group of 196 community-based volunteers with headache, 73 had a single headache classifiable as migraine (n = 22), tension-type (n = 33) or cervicogenic headache (n = 18); 57 subjects acted as controls. Range of movement, manual examination of cervical segments, cervical flexor and extensor strength, the cranio-cervical flexion test (CCFT), cross-sectional area of selected extensor muscles at C2 (ultrasound imaging) and cervical kinaesthetic sense were measured by a blinded examiner. In all but one measure (kinaesthetic sense), the cervicogenic headache group were significantly different from the migraine, tension-type headache and control groups (all P < 0.001). A discriminant function analysis revealed that collectively, restricted movement, in association with palpable upper cervical joint dysfunction and impairment in the CCFT, had 100% sensitivity and 94% specificity to identify cervicogenic headache. There was no evidence that the cervical musculoskeletal impairments assessed in this study were present in the migraine and tension-type headache groups. Further research is required to validate the predictive capacity of this pattern of impairment to differentially diagnose cervicogenic headache.

Developing global insight into RNA regulation.

Systematic dissection of the activity of RNA-binding proteins (RBPs) has begun to yield global insight into how they work. The paradigm we have used has been the study of Nova, a neuron-specific RBP targeted in an autoimmune neurologic disorder associated with cancer. We have developed a combination of biochemical, genetic, and bioinformatic methods to generate a global understanding of Nova's role as a splicing regulator. Genome-wide identification and validation of Nova target RNAs have yielded unexpected insights into the protein's mechanism of action, its role in neurobiology, and the unique roles RBPs have in the biology of the neuronal synapse. These studies provide us with a paradigm for understanding the role of RBPs in neurons and in disease and, more generally, with the hope that it will be feasible to develop a comprehensive understanding of posttranscriptional regulation.

FMRP RNA targets: identification and validation.

The Fragile X Syndrome is caused by the loss of function of the FMR1 gene (Pieretti et al. 1991. Cell 66, 817-822; O'Donnell & Warren 2002. Annu Rev Neurosci 25, 315-338]. Identification of the RNA targets to which FMRP binds is a key step in understanding the function of the protein and the cellular defects caused by its absence (Darnell et al. 2004 Ment Retard Dev Disabil Res Rev 10, 49-52). Here we discuss the current understanding of FMRP as an RNA-binding protein, the different approaches that have been taken to identify FMRP RNA targets and the relevance of some of these approaches to FMRP biology. In addition, we present evidence that point mutations in the K-homology (KH)1 or KH2 domains of FMRP abrogate its polyribosome association in transfected neuroblastoma cells but that the deletion of the RGG box does not. This suggests that RNA binding by the RGG box of FMRP may mediate other aspects of cellular mRNA metabolism such as mRNA localization or that it may have a role downstream of polyribosome association.

Effective antigen cross-presentation by prostate cancer patients' dendritic cells: implications for prostate cancer immunotherapy.

Despite the potency with which dendritic cells (DCs) are able to utilize the exogenous MHC I antigen cross-presentation pathway to cross-present antigen for the activation of killer T cells in model systems, concern about defects in immune function in cancer patients has led to uncertainty regarding whether immune cells derived from patients can effectively be used to generate tumor vaccines. We have undertaken a careful analysis of the potency of using DCs obtained from prostate cancer patients to cross-present antigen derived from human prostate tumor cells for the activation of antigen-specific T cells. Such DCs can be matured ex vivo into functionally active cells and are capable of cross-presenting influenza antigen derived from internalized apoptotic prostate tumor cells. Importantly, we demonstrate effective stimulation of both CD4+ and CD8+ T cells, as evident by production of IFN-gamma, and the ability of CD8+ T cells to differentiate into effector CTLs. These results, defining conditions in which prostate cancer patient DCs can efficiently utilize the cross-presentation pathway and in which apoptotic tumor can serve as a source of antigen for DCs to activate T cells, demonstrate that this system warrants clinical study as a potential immunotherapy.

Effect of ammonium and nitrate on ferric chelate reductase and nitrate reductase in Vaccinium species.

BACKGROUND AND AIMS: Most Vaccinium species have strict soil requirements for optimal growth, requiring low pH, high iron availability and nitrogen primarily in the ammonium form. These soils are limited and are often located near wetlands. Vaccinium arboreum is a wild species adapted to a wide range of soils, including high pH, low iron, and nitrate-containing soils. This broader soil adaptation in V. arboreum may be related to increased efficiency of iron or nitrate uptake compared with the cultivated Vaccinium species. METHODS: Nitrate, ammonium and iron uptake, and nitrate reductase (NR) and ferric chelate reductase (FCR) activities were compared in two Vaccinium species grown hydroponically in either nitrate or ammonia, with or without iron. The species studied were the wild V. arboreum and the cultivated V. corymbosum interspecific hybrid, which exhibits the strict soil requirements of most Vaccinium species. RESULTS: Ammonium uptake was significantly greater than nitrate uptake in both species, while nitrate uptake was greater in the wild species, V. arboreum, compared with the cultivated species, V. corymbosum. The increased nitrate uptake in V. arboreum was correlated with increased root NR activity compared with V. corymbosum. The lower nitrate uptake in V. corymbosum was reflected in decreased plant dry weight in this species compared with V. arboreum. Root FCR activity increased significantly in V. corymbosum grown under iron-deficient conditions, compared with the same species grown under iron-sufficient conditions or with V. arboreum grown under either iron condition. CONCLUSIONS: V. arboreum appears to be more efficient in acquiring nitrate compared with V. corymbosum, possibly due to increased NR activity and this may partially explain the wider soil adaptation of V. arboreum.

Prevalence of hypertension in children after early repair of coarctation of the aorta: a cohort study using casual and 24 hour blood pressure measurement.

OBJECTIVE: To study the prevalence of hypertension in a cohort of patients using the current strategy of repair in early childhood. PATIENTS: The cohort of patients with coarctation of the aorta born between 1983 and 1992. INTERVENTION: Casual (mean of three resting readings) and 24 hour blood pressure were measured in 119 children and compared with data from 1034 normal controls. The arch repair and left ventricular parameters were assessed using Doppler echocardiography. RESULTS: Median ages at first intervention and at blood pressure measurement were 0.2 years (interquartile range 0.04-2.0) and 12.0 years (9.0-14.5), respectively. Doppler velocity in the descending aorta was significantly associated with blood pressure (r = 0.28, p = 0.002 for casual systolic blood pressure (SBP); r = 0.26, p = 0.005 for mean 24 hour SBP). Patients were classified as having "no" (n = 70) or "mild" (n = 49) arch obstruction. Casual SBP was > 95th centile in 28% (34 of 119) overall and in 21% (15 of 70) of the no arch obstruction group. Mean 24 hour SBP was > 95th centile in 30% (36 of 119) overall and in 19% (13 of 70) of the no obstruction group. The sensitivity and specificity of casual SBP in detecting increased 24 hour SBP were 66% and 88%, respectively. CONCLUSIONS: This unique study of a large cohort of patients treated for coarctation in early childhood showed that a disappointingly high prevalence of hypertension is already apparent in children aged 7-16 years in the absence of significant arch obstruction, whether assessed by 24 hour or by casual blood pressure measurement.

Neuronal signaling through alternative splicing: some exons CaRRE.

Alternative splicing represents a mechanism by which a single gene can be used to create proteins with different functions. Neurons use alternative splicing to produce channels with different sequences and biophysical or regulatory properties. O'Donovan and Darnell discuss a mechanism by which neurons can alter channel splicing in response to neuronal activity through a signal generated by calcium and calcium/calmodulin-dependent kinase activity.

Fragile X mental retardation protein targets G quartet mRNAs important for neuronal function.

Loss of fragile X mental retardation protein (FMRP) function causes the fragile X mental retardation syndrome. FMRP harbors three RNA binding domains, associates with polysomes, and is thought to regulate mRNA translation and/or localization, but the RNAs to which it binds are unknown. We have used RNA selection to demonstrate that the FMRP RGG box binds intramolecular G quartets. This data allowed us to identify mRNAs encoding proteins involved in synaptic or developmental neurobiology that harbor FMRP binding elements. The majority of these mRNAs have an altered polysome association in fragile X patient cells. These data demonstrate that G quartets serve as physiologically relevant targets for FMRP and identify mRNAs whose dysregulation may underlie human mental retardation.

Microarray identification of FMRP-associated brain mRNAs and altered mRNA translational profiles in fragile X syndrome.

Fragile X syndrome results from the absence of the RNA binding FMR protein. Here, mRNA was coimmunoprecipitated with the FMRP ribonucleoprotein complex and used to interrogate microarrays. We identified 432 associated mRNAs from mouse brain. Quantitative RT-PCR confirmed some to be >60-fold enriched in the immunoprecipitant. In parallel studies, mRNAs from polyribosomes of fragile X cells were used to probe microarrays. Despite equivalent cytoplasmic abundance, 251 mRNAs had an abnormal polyribosome profile in the absence of FMRP. Although this represents <2% of the total messages, 50% of the coimmunoprecipitated mRNAs with expressed human orthologs were found in this group. Nearly 70% of those transcripts found in both studies contain a G quartet structure, demonstrated as an in vitro FMRP target. We conclude that translational dysregulation of mRNAs normally associated with FMRP may be the proximal cause of fragile X syndrome, and we identify candidate genes relevant to this phenotype.

Dendritic cell maturation is required for the cross-tolerization of CD8+ T cells.

In vivo models have shown that tissue-restricted antigen may be captured by bone marrow-derived cells and cross-presented for the tolerization of CD8+ T cells. Although these studies have shown peripheral tolerization of CD8+ T cells, the mechanism of antigen transfer and the nature of the antigen-presenting cell (APC) remain undefined. We report here the establishment of an in vitro system for the study of cross-tolerance and show that dendritic cells (DCs) phagocytose apoptotic cells and tolerize antigen-specific CD8+ T cells when cognate CD4+ T helper cells are absent. Using this system, we directly tested the "two-signal" hypothesis for the regulation of priming versus tolerance. We found that the same CD83+ myeloid-derived DCs were required for both cross-priming and cross-tolerance. These data suggested that the current model for peripheral T cell tolerance, "signal 1 in the absence of signal 2", requires refinement: the critical checkpoint is not DC maturation, but instead the presence of a third signal, which is active at the DC-CD4+ T cell interface.

Children's respiratory health and daily particulate levels in 10 nonurban communities.

We conducted a study to assess the association between the acute respiratory health of children and the levels of particulates in communities near and away from active opencast coal mines. The study enrolled children aged 1-11 years from the general population of five socioeconomically matched pairs of nonurban communities in northern England. Diaries of respiratory events were collected for 1405 children, and information was collected on the consultations of 2442 children with family/general practitioners over the 6-week study periods during 1996-1997, with concurrent monitoring of particulate levels. The associations found between daily PM(10) levels and respiratory symptoms were frequently small and positive and sometimes varied between communities. The magnitude of these associations were in line with those from previous studies, even though daily particulate levels were low, and the children were drawn from the general population, rather than from the population with respiratory problems. The associations among asthma reliever use, consultations with general practitioners, and daily particulate levels were of a similar strength but estimated less precisely. The strength of association between all respiratory health measures and particulate levels was similar in communities near and away from opencast coal mining sites.

Consultations of children living near open-cast coal mines.

Because of local concerns, general practitioner consultation rates in children living in communities close to and away from open-cast mines were compared. Information on consultations was collected on 2,442 children 1-11 years of age living in five socioeconomically matched pairs of open-cast and control communities in northern England. The data collection periods were 6 weeks each during 1996-1997 and the 52-week periods preceding these weeks. Consultations were categorized as respiratory, skin and eye conditions (possibly exacerbated by particulate matter), or other conditions. Over the 6-week periods, children in 4/5 pairs of open-cast and control communities had similar consultation rates for all conditions combined [2.7 vs. 2.4 per person-year; odds ratio (OR) = 1.1; 95% confidence interval (CI), 0.96-1.3). Consultations were higher in the open-cast communities for respiratory, skin, and eye conditions (2.1 vs. 1.5 per person-year; OR = 1.4; 95% CI, 1.2-1.7), and respiratory conditions alone (1.5 vs. 1.1 per person-year; OR = 1.5; 95% CI, 1.2-1.8). However, increases in consultation rates in open-cast communities were generally not seen over the portions of the 52-week periods when the open-cast sites were either active or inactive.

Paraneoplastic neurologic disease antigens: RNA-binding proteins and signaling proteins in neuronal degeneration.

Studies of the disorders known as paraneoplastic neurologic degenerations exemplify the successful application of modern molecular biological techniques to diseases, yielding, even for these extremely rare disorders, wide-ranging insight into basic neurobiology, tumor immunity, and autoimmune neurologic disease. Immune responses to paraneoplastic neurologic degeneration antigens, also called onconeural antigens, have been exploited to clone and characterize a number of neuron-specific proteins, including several RNA-binding proteins and new kinds of signaling molecules. The biology and functions of these proteins are reviewed, and a model in which their functions are related to the pathogenesis of autoimmune neurologic disease is discussed.