Localization of taurine transporters, taurine, and H-3 taurine accumulation in the rat retina, pituitary, and brain

The nervous system contains an abundance of taurine, a neuroactive sulfonic acid. Antibodies were generated against two cloned high-affinity taurine transporters, referred to in this study as TAUT-1 and TAUT-2. The distribution of such was compared with the distribution of taurine in the rat brain, pituitary, and retina. The cellular pattern of [H-3] taurine uptake in brain slices, pituitary slices, and retinas was examined by autoradiography. TAUT-2 was predominantly associated with glial cells, including the Bergmann glial cells of the cerebellum and astrocytes in brain areas such as hippocampus. Low-level labeling for TAUT-2 was also observed in some neurones such as CA1 pyramidal cells. TAUT-1 distribution was more limited; in the posterior pituitary TAUT-1 was associated with the pituicytes but was absent from glial cells in the intermediate and anterior lobes. Conversely, in the brain TAUT-1 was associated with cerebellar Purkinje cells and, in the retina, with photoreceptors and bipolar cells. Our data suggest that intracellular taurine levels in glial cells and neurons may be regulated in part by specific high-affinity taurine transporters. The heterogeneous distribution of taurine and its transporters in the brain does not reconcile well with the possibility that taurine acts solely as a ubiquitous osmolyte in nervous tissues. (C) 2002 Wiley-Liss, Inc.

Micronesian banana, taro, and other foods: newly recognized sources of provitamin A and other carotenoids

Vitamin A deficiency (VAD) and chronic diseases are serious problems in the Federated States of Micronesia and other Pacific island countries. Nutrition education programs to address these in Micronesia have had limited success, partly due to lack of information on nutrient content in local foods. The study objective was to identify local plant foods rich in provitamin A and other carotenoids that have high levels of cultural acceptability. Food cultivars likely to be carotenoid-rich (suggested by coloration) were identified using an ethnographic approach including key informant interviews. Raw and cooked samples (mostly cultivars previously not analyzed) of 12 banana, 13 giant swamp taro, 10 breadfruit cultivars and four other local foods were analyzed by high-performance liquid chromatography. Many banana and taro cultivars were found with significant levels of beta- and alpha-carotene; the beta-carotene levels ranged from 30 to 2780 mug/100 g (banana) and. 50 to 2040 mug/100 g (taro). The results highlight the potential significance of cultivar differences in human nutrition, important for evaluation of the diet, establishment of locally relevant dietary guidelines, and research on the relationship between diet, health, and disease. These highly acceptable food cultivars could play an important role in VAD and chronic disease prevention programs in the Pacific. (C) 2003 Elsevier Science Ltd. All rights reserved.

Genetic and environmental sources of covariance between reading tests used in neuropsychological assessment and IQ subtests

In this study, we examined genetic and environmental influences on covariation among two reading tests used in neuropsychological assessment (Cambridge Contextual Reading Test [CCRT], [Beardsall, L., and Huppert, F. A. ( 1994). J. Clin. Exp. Neuropsychol. 16: 232 - 242], Schonell Graded Word Reading Test [SGWRT], [ Schonell, F. J., and Schonell, P. E. ( 1960). Diagnostic and attainment testing. Edinburgh: Oliver and Boyd.]) and among a selection of IQ subtests from the Multidimensional Aptitude Battery (MAB), [Jackson, D. N. (1984). Multidimensional aptitude battery, Ontario: Research Psychologists Press.] and the Wechsler Adult Intelligence Scale-Revised (WAIS-R) [Wechsler, D. (1981). Manual for the Wechsler Adult Intelligence Scale-Revised (WAIS-R). San Antonio: The Psychological Corporation]. Participants were 225 monozygotic and 275 dizygotic twin pairs aged from 15 years to 18 years ( mean, 16 years). For Verbal IQ subtests, phenotypic correlations with the reading tests ranged from 0.44 to 0.65. For Performance IQ subtests, phenotypic correlations with the reading tests ranged from 0.23 to 0.34. Results of Structural Equation Modeling (SEM) supported a model with one genetic General factor and three genetic group factors ( Verbal, Performance, Reading). Reading performance was influenced by the genetic General factor ( accounting for 13% and 20% of the variance for the CCRT and SGWRT, respectively), the genetic Verbal factor ( explaining 17% and 19% of variance for the CCRT and SGWRT), and the genetic Reading factor ( explaining 21% of the variance for both the CCRT and SGWRT). A common environment factor accounted for 25% and 14% of the CCRT and SGWRT variance, respectively. Genetic influences accounted for more than half of the phenotypic covariance between the reading tests and each of the IQ subtests. The heritabilities of the CCRT and SGWRT were 0.54 and 0.65, respectively. Observable covariance between reading assessments used by neuropsychologists to estimate IQ and IQ subtests appears to be largely due to genetic effects.

Sources of stress experienced by occupational therapists and social workers in mental health settings

This study examined the sources of stress experienced by occupational therapists and social workers employed in Australian public mental health services and identified the demographic and work-related factors related to stress using a cross-sectional survey design. Participants provided demographic and work-related information and completed the Mental Health Professionals Stress Scale. The overall response rate to the survey was 76.6%, consisting of 196 occupational therapists and 108 social workers. Results indicated that lack of resources, relationships and conflicts with other professionals, workload, and professional self-doubt were correlated with increased stress. Working in case management was associated with stress caused by client-related difficulties, lack of resources, and professional self-doubt. The results of this study suggest that Australian occupational therapists and social workers experience stress, with social workers reporting slightly more overall stress than occupational therapists. Copyright © 2005 Whurr Publishers Ltd.

The effects of ambient music on simulated anaesthesia monitoring

We examined the effect of no music, classical music or rock music on simulated patient monitoring. Twenty-four non-anaesthetist participants with high or low levels of musical training were trained to monitor visual and auditory displays of patients' vital signs. In nine anaesthesia test scenarios, participants were asked every 50-70 s whether one of five vital signs was abnormal and the trend of its direction. Abnormality judgements were unaffected by music or musical training. Trend judgements were more accurate when music was playing (p = 0.0004). Musical participants reported trends more accurately (p = 0.004), and non-musical participants tended to benefit more from music than did the musical participants (p = 0.063). Music may provide a pitch and rhythm standard from which participants can judge changes in vital signs from auditory displays. Nonetheless, both groups reported that it was easier to monitor the patient with no music (p = 0.0001), and easier to rely upon the auditory displays with no music (p = 0.014).

Localization and movement of mineral oil in plants by fluorescence and confocal microscopy

Fluorescence and confocal laser scanning microscopy were explored to investigate the movement and localization of mineral oils in citrus. In a laboratory experiment, fluorescence microscopy observation indicated that when a 'narrow' distillation fraction of an nC23 horticultural mineral oil was applied to adaxial and opposing abaxial leaf surfaces of potted orange [Citrus x aurantium L. (Sapindales: Rutaceae)] trees, oil penetrated steadily into treated leaves and, subsequently, moved to untreated petioles of the leaves and adjacent untreated stems. In another experiment, confocal laser scanning microscopy was used to visualize the penetration into, and the subsequent cellular distribution of, an nC24 agricultural mineral oil in C. trifoliata L. seedlings. Oil droplets penetrated or diffused into plants via both stomata and the cuticle of leaves and stems, and then moved within intercellular spaces and into various cells including phloem and xylem. Oil accumulated in droplets in intercellular spaces and within cells near the cell membrane. Oil entered cells without visibly damaging membranes or causing cell death. In a field experiment with mature orange trees, droplets of an nC23 horticultural mineral oil were observed, by fluorescence microscopy, in phloem sieve elements in spring flush growth produced 4-5 months and 16-17 months after the trees were sprayed with oil. These results suggest that movement of mineral oil in plants is both apoplastic via intercellular spaces and symplastic via plasmodesmata. The putative pattern of the translocation of mineral oil in plants and its relevance to oil-induced chronic phytotoxicity are discussed.

The role of different sources of communication and trust in reducing change-related uncertainties during organisational change

The current paper presents a qualitadve study of the role of different sources of communicadon in reducing change-related uncertaintj' experienced by employees during organisadonal change. The paper examines the role of trust in influencing how employees' appraise informadon from different sources within organisadons. Interviews with 19 employees from a range of organisadons idendfy the different types of change-related uncertaindes experienced during change. In addidon, the different sources of communicadon utilised by employees are idendfied and the role each source plays in reducing the different t}'pes of uncertaint}' invesdgated. From employee responses it is evident that t)'pically supervisors are the best source of change informadon, while communicadon from senior management usually focuses on strategic issues. Employees indicate that communicadon with coworkers operates as a support mechanism providing an avenue to share grievances arising from the change. Finally, trust is idendfied as playing an important role in influencing who employees go to for informadon when experiencing uncertainty'. ImpUcadons for change management research in addidon to pracdcal implicadons are discussed.

Evaluation and comparison of mammalian subcellular localization prediction methods

Background: Determination of the subcellular location of a protein is essential to understanding its biochemical function. This information can provide insight into the function of hypothetical or novel proteins. These data are difficult to obtain experimentally but have become especially important since many whole genome sequencing projects have been finished and many resulting protein sequences are still lacking detailed functional information. In order to address this paucity of data, many computational prediction methods have been developed. However, these methods have varying levels of accuracy and perform differently based on the sequences that are presented to the underlying algorithm. It is therefore useful to compare these methods and monitor their performance. Results: In order to perform a comprehensive survey of prediction methods, we selected only methods that accepted large batches of protein sequences, were publicly available, and were able to predict localization to at least nine of the major subcellular locations (nucleus, cytosol, mitochondrion, extracellular region, plasma membrane, Golgi apparatus, endoplasmic reticulum (ER), peroxisome, and lysosome). The selected methods were CELLO, MultiLoc, Proteome Analyst, pTarget and WoLF PSORT. These methods were evaluated using 3763 mouse proteins from SwissProt that represent the source of the training sets used in development of the individual methods. In addition, an independent evaluation set of 2145 mouse proteins from LOCATE with a bias towards the subcellular localization underrepresented in SwissProt was used. The sensitivity and specificity were calculated for each method and compared to a theoretical value based on what might be observed by random chance. Conclusion: No individual method had a sufficient level of sensitivity across both evaluation sets that would enable reliable application to hypothetical proteins. All methods showed lower performance on the LOCATE dataset and variable performance on individual subcellular localizations was observed. Proteins localized to the secretory pathway were the most difficult to predict, while nuclear and extracellular proteins were predicted with the highest sensitivity.