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Background: The issue of whether there exists an own-effect on facial recognition in the elderly remains equivocal. Moreover, currently the literature of this issue in pathological aging is little. Objective: Our study was thus to explore the issue in both of healthy older people and patients with AD Methods: In study 1, 27 older and 31 younger healthy adults were recruited; in study 2, 27 healthy older adults and 80 patients (including subjective cognitive decline (SCD), mild cognitive impairment (MCI), and Alzheimer’s disease (AD) groups) were recruited. Participants received the Taiwan Facial Emotion Recognition Task (FER Task), and a clinical neuropsychological assessment. Results: No significant differences on the FER test were found among our groups, except for sadness recognition in which our MCI and AD patients’ scores were remarkably lower than their healthy counterparts. The own-age effect was not significantly evident in healthy younger and older adults, except for recognizing neutral photos. Our patients with MCI and AD tended to have the effect, particularly for the sad recognition in which the effect was significantly evident in terms of error features (mislabeling it as anger in younger-face and neutral in older-face photos). Conclusion: Our results displayed no remarkable own-age effect on facial emotional recognition in the healthy elderly (including SCD). However, it did not appear the case for MCI and AD patients, especially their recognizing those sadness items, suggesting that an inclusion of the FER task particularly involving those items of low-intensity emotion in clinical neuropsychological assessment might be contributory to the early detection of AD-related pathological individuals.

Recent study has suggested semantic memory deterioration may be the earliest cognitive changes in Alzheimer's disease (AD). Few previous researchers have investigated specific changes in the semantic structures in the memory of patients with amnestic mild cognitive impairment (aMCI). This study examined the clustering performance in semantic fluency among 160 participants in various MCI subgroups (aMCI single domain, aMCI-sd, n = 30; aMCI multiple domain, aMCI-md, n = 30; non-aMCI multiple domain, naMCI-md, n = 10) as well as a group of mildly impaired individuals with dementia of AD type (DAT, n = 20), and a group of healthy controls (HC, n = 70). Compared with HC group, DAT patients presented deficient clustering in each semantic category related to living things. aMCI-sd group presented defective clustering when dealing with the clustering of items that may be more strongly associated with praxis and perceptual information in the categories that included inanimate living things. aMCI-md group displayed defective patterns similar to those in the aMCI-sd group; however, they displayed more profound deficits in clustering that may require perceptual information. Patients with naMCI-md preserved their ability to perform clustering on all of the categories. The poor clustering of items that may be more strongly associated with praxis could be used as a means of predicting conversion from aMCI-sd to DAT, whereas performance on items that may require perceptual information could be used to predict conversion among aMCI-md patients. These findings demonstrate the degree to which the semantic structures in memory can be used for the assessment of aMCI patients and prediction of conversion to DAT.

Background Optimization of vascular risk factor control is emerging as an alternative approach to improve cognitive outcomes in Alzheimer’s disease, although its efficacy is still under debate. We aimed to investigate the contribution of vascular risk factors on Alzheimer’s biomarkers and conversion rate to dementia in subjects with mild cognitive impairment (MCI) with low cerebral small vessel disease burden. Methods Two hundred ninety-five newly diagnosed MCI subjects were enrolled from March 2005 to May 2017 for a cross-sectional assessment of vascular risk factors and Alzheimer’s plasma and imaging biomarkers, followed by a cognitive outcome assessment 24 months after enrollment. The association between vascular risk factors and Alzheimer’s biomarkers were tested using multivariable linear regression models adjusted with age, gender, education, and APOE ε4 allele. The association between vascular risk factors and conversion to dementia was tested using multivariable logistic regression models adjusted with age, gender, education, and baseline Mini-Mental State Examination (MMSE) score. Results At baseline, higher low-density lipoprotein (LDL) cholesterol level was associated with more advanced plasma biomarkers, including Aβ42/Aβ40 ratio (P = 0.012) and tau level (P = 0.001). A history of hypertension was associated with more advanced white matter hyperintensity (P = 0.011), while statin therapy for dyslipidemia was associated with less advanced white matter hyperintensity (P = 0.002). At 24 months, individual vascular risk factor was not significantly associated with cognitive outcome. By contrast, statin therapy for dyslipidemia was associated with reduced conversion to dementia (adjusted OR = 0.191, 95% CI = 0.062~0.586, P = 0.004). Conclusions For MCI subjects, dyslipidemia may contribute to AD-related neurodegeneration while hypertension may contribute to vascular pathology. The association between statin therapy for dyslipidemia and reduced conversion to dementia supports further interventional study to evaluate the potential beneficial effect of statin in MCI subjects.

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This study focuses on serious virtual reality games, and how users can increase their understanding of the sustainable innovation learning (SIL) model and their familiarity with sustainable development strategies. &ldquo, Users&rdquo, of serious games consists of all possible target groups that are interested in attaining knowledge of sustainability through the use of games that are designed for a purpose beyond entertainment, in this case, for sustainable education. This research investigates the sustainable innovation experiential learning model by using a virtual chemistry laboratory to affect academic achievement. A questionnaire was completed by students who had used the virtual lab, and structural equation modeling (SEM) was applied for analysis. Importance-performance matrix analysis (IPMA) was able to help expand the basic partial least square (PLS)-SEM result with the fraction. The results show that experiential learning significantly affects learning motivation and academic achievement. Cognitive load and self-efficacy significantly affect learning motivation. Involvement significantly affects academic achievement. The virtual chemistry laboratory significantly affects academic achievement. Students who used the sustainability innovation experiential learning model obtained a better understanding of the chemical concepts. Moreover, a virtual lab promotes students&rsquo, motivation in regard to chemistry.

Although laccase is involved in the biotransformation of 2,4,6-trinitrotoluene (TNT), little is known regarding the effect of E. coli laccase on TNT biotransformation. In this study, E. coli K12 served as the parental strain to construct a laccase deletion strain and two laccase-overexpressing strains. These E. coli strains were used to investigate the effect of laccase together with copper ions on the efficiency of TNT biotransformation, the variety of TNT biotransformation products generated and the toxicity of the TNT metabolites. The results showed that the laccase level was not relevant to TNT biotransformation in the soluble fraction of the culture medium. Conversely, TNT metabolites varied in the insoluble fraction analyzed by thin-layer chromatography (TLC). The insoluble fraction from the laccase-null strain showed fewer and relatively fainter spots than those detected in the wild-type and laccase-overexpressing strains, indicating that laccase expression levels were interrelated determinants of the varieties and amounts of TNT metabolites produced. In addition, the aquatic invertebrate Tigriopus japonicus was used to assess the toxicity of the TNT metabolites. The toxicity of the TNT metabolite mixture increased when the intracellular laccase level in strains increased or when purified E. coli recombinant Laccase (rLaccase) was added to the culture medium. Thus, our results suggest that laccase activity must be considered when performing microbial TNT remediation.

Frontotemporal lobar degeneration (FTLD) is a neurodegenerative disease that typically presents as progressive behavioral changes or language deficits; and is associated with atrophy and hypometabo...

Objective Evaluating social-functioning impairments in patients with Alzheimer's disease (AD) objectively is essential for clinical service. However, the existing instruments lack representative content, consensus on purposes of use, and adequate scoring systems and samples. This study was thus to develop a social functioning scale for patients: the Social Functioning Scale for Alzheimer's Disease (SFSAD). Method Questionnaires were analyzed from 142 AD patients, 30 patients with amnestic mild cognitive impairment (aMCI), and 50 normal controls. Results Based on the literature review and experts' opinions, the final scale includes 20 items in four subscales. The SFSAD showed high internal consistency coefficients (Cronbach's α = .97) and test-retest reliability (r = .99) coefficients. The content validity was desirable, and the criterion-related validity was demonstrated by a significant association with the MMSE, the IADL, and the Barthel ADL. The discriminant validity of the scale was also demonstrated as the level of social-functioning impairment was significantly related to the degree of dementia, and for construct validity, our findings supported the structure of the four-factor hypothesized model. Conclusions The SFSAD is thus a practical, psychometrically sound, and easy-to-administer measure to evaluate social functioning of AD and aMCI in brisk clinical settings.

Background/Purpose: Researchers have recently proposed a preclinical stage of dementia of Alzheimer's type (DAT), referred to as subjective memory impairment (SMI), with the aim of developing methods for the early detection of DAT and subsequent intervention. It has been proposed that the objective memory functions of individuals with SMI are normal; however, arbitrary and semantic associations are both used to describe the processes of memory. No previous studies have investigated these processes among individuals with SMI. Methods: Cross-sectional analysis was used to compare the memory function of individuals with SMI, amnestic mild cognitive impairment (aMCI), or DAT. One hundred and eighty-three participants were recruited from the Memory Clinic of National Taiwan University Hospital and communities in northern Taiwan, including individuals with no memory complaints (HC, n = 30) and individuals with SMI (n = 61), aMCI-single domain (n = 24), aMCI-multiple domain (n = 33), or DAT (n = 35). The Word Sequence Learning Test (WSLT) was used to assess the formation of arbitrary associations and the Logical Memory subtest of the Wechsler Memory Scale-Third Edition was used to assess the formation of semantic associations. Results: Compared to the HC group, the SMI group performed poorly only on the WSLT, whereas the other groups performed poorly on both of the memory tasks. This study demonstrated that SMI individuals tend to perform poorly in the formation of arbitrary associations. Conclusion: Our findings suggest that tasks requiring arbitrary associations may provide greater sensitivity in the detection cognitive changes associated with preclinical DAT. Keywords: Alzheimer's disease, Mild cognitive impairment, Neuropsychology, Dementia

Terrestrial hydrocarbon seeps are an important source of naturally emitted methane over geological time. The exact community compositions responsible for carbon cycling beneath these surface features remain obscure. As sulfate reduction represents an essential process for anoxic organic mineralization, this study collected muddy fluids from a high-temperature hydrocarbon seep in Taiwan and analyzed community structures of sulfate-supplemented sediment slurries incubated anoxically at elevated temperatures. The results obtained demonstrated that sulfate consumption occurred between 40°C and 80°C. Dominant potential sulfate reducers included Desulfovibrio spp., Desulfonatronum spp., Desulforhabdus spp., and Desulfotomaculum spp. at 40°C, Thermodesulfovibrio spp. at 50°C, Thermodesulfovibrio spp. and Thermacetogenium spp. at 60°C, Thermacetogenium spp. and Archaeoglobus spp. at 70°C, and Archaeoglobus spp. at 80°C. None of these potential sulfate reducers exceeded 7% of the community in the untreated sample. Since no exogenous electron donor was provided during incubation, these sulfate reducers appeared to rely on the degradation of organic matter inherited from porewater and sediments. Aqueous chemistry indicated that fluids discharged in the region represented a mixture of saline formation water and low-salinity surface water; therefore, these lines of evidence suggest that deeply-sourced, thermophilic and surface-input, mesophilic sulfate-reducing populations entrapped along the subsurface fluid transport could respond rapidly once the ambient temperature is adjusted to a range close to their individual optima.

Hydrocarbon seepage is a surface expression where fluids mixed with sediments and hydrocarbons are expelled through fracture systems that potentially tap into gas–petroleum reservoirs. Hydrocarbons released from most seeps appear to be thermogenic on the basis of their relative abundance and isotopic composition. The potential for subsurface microbial processes modifying these geochemical fingerprints remains poorly constrained. In this study, microcosm incubations were conducted on mud slurries supplied with/without various methanogenic precursors at temperatures ranging from ambient conditions to 90 °C, in order to assess microbial CH4 formation in the subsurface beneath hydrocarbon seeps. The analyses indicated that CH4 production was positive at ⩽80 °C, regardless of whether or not or which precursors were added. However, the pattern of CH4 production rates varied with the precursor and temperature. In general, the optimum CH4 production from H2/CO2 and formate occurred over a wide range of temperatures (⩾40 °C), whereas that from acetate, methanol and methylamine was restricted to relatively lower temperatures (40–50 °C). The CH4 recoveries, together with the C isotopic compositions of CH4, further indicated that the quantities of CH4 produced could not completely account for the quantities of precursor consumed, suggesting that a complex metabolic network was involved in the transformation of the added precursor and organic C inherited from inoculated sediments. Microbial CH4 was estimated to constitute 7–61% of the CH4 observed using experimentally-derived apparent isotope fractionations as the end member compositions. This illustrates the possibility that microbial CH4 produced at shallower depths could quantitatively and isotopically alter deeply-sourced thermogenic CH4 in hydrocarbon seep environments.

Olfactory sensory neurons (OSNs) extend their axons from the nasal epithelium to their odorant receptor-dependent locations in the olfactory bulb. Previous studies have identified several membrane proteins along the projection pathway, and on OSN axons themselves, which regulate this process; however, little is known about the signaling mechanisms through which these factors act. We have identified and characterized Rap1gap2, a novel small GTPase regulator, in OSNs during early postnatal mouse development. Rap1gap2 overexpression limits neurite outgrowth and branching in Neuro-2a cells, and counteracts Rap1-induced augmentation of neurite outgrowth. Rap1gap2 expression is developmentally regulated within OSNs, with high expression in early postnatal stages that ultimately drops to undetectable levels by adulthood. This temporal pattern coincides with an early postnatal plastic period of OSN innervation refinement at the OB glomerular layer. Rap1gap2 stunts OSN axon outgrowth when overexpressed in vitro, while knock-down of Rap1gap2 transcript results in a significant increase in axon length. These results indicate an important role of Rap1gap2 in OSN axon growth dynamics during early postnatal development.

Terrestrial mud volcanism represents the prominent surface geological feature, where fluids and hydrocarbons are discharged along deeply rooted structures in tectonically active regimes. Terrestrial mud volcanoes (MVs) directly emit the major gas phase, methane, into the atmosphere, making them important sources of greenhouse gases over geological time. Quantification of methane emission would require detailed insights into the capacity and efficiency of microbial metabolisms either consuming or producing methane in the subsurface, and establishment of the linkage between these methane-related metabolisms and other microbial or abiotic processes. Here we conducted geochemical, microbiological and genetic analyses of sediments, gases, and pore and surface fluids to characterize fluid processes, community assemblages, functions and activities in a methane-emitting MV of southwestern Taiwan. Multiple lines of evidence suggest that aerobic/anaerobic methane oxidation, sulfate reduction and methanogenesis are active and compartmentalized into discrete, stratified niches, resembling those in marine settings. Surface evaporation and oxidation of sulfide minerals are required to account for the enhanced levels of sulfate that fuels subsurface sulfate reduction and anaerobic methanotrophy. Methane flux generated by in situ methanogenesis appears to alter the isotopic compositions and abundances of thermogenic methane migrating from deep sources, and to exceed the capacity of microbial consumption. This metabolic stratification is sustained by chemical disequilibria induced by the mixing between upward, anoxic, methane-rich fluids and downward, oxic, sulfate-rich fluids.

Introduction This study aimed to investigate the feasibility of predicting the long–term effects of cholinesterase inhibitors (ChEI) with common clinical neuroimaging parameters of Alzheimer’s disease, including medial temporal lobe atrophy (MTA) and white matter hyperintensity (WMH). Method A cohort of 353 patients with very mild to moderate Alzheimer’s disease received cholinesterase inhibitors and were followed for a median of 46.6 months. Baseline clinical data, including age, educational level, Clinical Dementia Rating (CDR), Taiwanese Mental State Examination (TMSE), and visual scoring for MTA and WMH were tested as possible predictive factors that influence the survival from a TMSE decline of at least 3 points. Results During the follow-up period, 162(46 %) patients had a significant TMSE decline. Patients with age-adjusted prominent MTA had a significantly shorter TMSE-decline free interval than those without (43.4 ± 4.5 months vs. 68.2 ± 9.5 months, log rank test p-value =0.001). However, the severity of WMH does not significantly influence cognitive outcomes. Cox regression analysis identified that younger age at the time of starting ChEI (p Conclusions Younger age at the time of starting ChEI and higher visual scoring of MTA may imply a more advanced Alzheimer’s pathology. WMH load is not a prognostic indicator of treatment response to ChEI.

The aim of this study was to identify the neuropsychological features in patients with temporal lobe epilepsy (TLE) and their correlation with seizure-related variables. For this purpose, we carried out a retrospective analysis of data from 65 patients with TLE who had undergone a comprehensive neuropsychological assessment. The results suggest that the majority of patients with TLE were impaired in more than one cognitive domain, and among these patients, the mean proportions with defective semantic memory, language, motor/psychomotor speed, verbal episodic memory, and executive function were >50% each. Moreover, age at seizure onset was the strongest predictor of general intellectual impairment, and number of antiepileptic drugs and seizure frequency could significantly predict deficits in verbal memory, language, and psychomotor speed. However, epilepsy duration was a less potent predictor of cognitive deficit than has been reported in cross-sectional studies.

Throughout the nervous system, neurons restrict their connections to specific depths or “layers” of their targets to constrain the type and number of synapses they make. Despite the importance of lamina-specific synaptic connectivity, the mechanisms that give rise to this feature in mammals remain poorly understood. Here we examined the cellular events underlying the formation of lamina-specific retinal ganglion cell (RGC) axonal projections to the superior colliculus (SC) of the mouse. By combining a genetically encoded marker of a defined RGC subtype (OFF-αRGCs) with serial immunoelectron microscopy, we resolved the ultrastructure of axon terminals fated for laminar stabilization versus those fated for removal. We found that OFF-αRGCs form synapses across the full depth of the retinorecipient SC before undergoing lamina-specific arbor retraction and synapse elimination to arrive at their mature, restricted pattern of connectivity. Interestingly, we did not observe evidence of axon degeneration or glia-induced synapse engulfment during this process. These findings indicate that lamina-specific visual connections are generated through the selective stabilization of correctly targeted axon arbors and suggest that the decision to maintain or eliminate an axonal projection reflects the molecular compatibility of presynaptic and postsynaptic neurons at a given laminar depth.

Our aim in this study was to explore the neural substrates of executive function in frontal and nonfrontal white matter using diffusion tensor imaging (DTI). We studied the relationship between executive dysfunction and DTI measurements on 13 subjects with amnesic mild cognitive impairment (aMCI), 11 subjects with early Alzheimer's disease (AD), and 16 control subjects. All participants underwent an examination of their intelligence, memory, and executive function and were subjected to DTI. Both aMCI and early AD subjects showed executive function impairment with differential performance in frontal‐related behaviors. Both aMCI and early AD subjects showed increased mean diffusivity in the genu of the corpus callosum and left frontal periventricular white matter (PVWM), whereas subjects with early AD showed an additional decrease in the fractional anisotropy of bilateral frontal PVWM and in the genu of the corpus callosum. The frontal PVWM was associated with performance on the Verbal Fluency Test, the Wisconsin Card Sorting Test (WCST), and Part B of the Trail Making Test. The parietal PVWM was associated with perseverative errors on the WCST and Part A of the Trail Making Test. In summary, executive function was impaired in subjects with aMCI and early AD and was associated with frontal and parietal PVWM changes. These changes may be due to early AD degeneration of the lateral cholinergic projections or to early change of the superior longitudinal fasciculus. Hum Brain Mapp, 2009. © 2009 Wiley‐Liss, Inc.

Olfactory sensory neurons synapse with mitral cells to form stereotyped connections in the olfactory bulb (OB). Mitral cell apical dendrites receive input from olfactory sensory neurons expressing the same odorant receptor. During development, this restricted dendritic targeting of mitral cells is achieved through eliminating elaborated dendritic trees to a single apical dendrite. Through a genome-wide microarray screen, we identified TARSH (Target of NESH SH3) as a transiently expressed molecule in mitral cells during the dendritic refinement period. TARSH expression is restricted to pyramidal neurons along the main olfactory pathway, including the anterior olfactory nucleus and piriform cortex. The dynamic TARSH expression is not altered when odor-evoked activity is blocked by naris closure or in AC3 knockout mice. We also demonstrate that TARSH is a secreted protein. In dissociated OB cultures, secreted TARSH promotes the reduction of mitral cell dendritic complexity and restricts dendritic branching and outgrowth of interneurons. Dendritic morphological changes were also observed in mitral cells overexpressing TARSH themselves. We propose that TARSH is part of the genetic program that regulates mitral cell dendritic refinement.

This study aimed to investigate the feasibility of predicting the long–term effects of cholinesterase inhibitors (ChEI) with common clinical neuroimaging parameters of Alzheimer’s disease, including medial temporal lobe atrophy (MTA) and white matter hyperintensity (WMH). A cohort of 353 patients with very mild to moderate Alzheimer’s disease received cholinesterase inhibitors and were followed for a median of 46.6 months. Baseline clinical data, including age, educational level, Clinical Dementia Rating (CDR), Taiwanese Mental State Examination (TMSE), and visual scoring for MTA and WMH were tested as possible predictive factors that influence the survival from a TMSE decline of at least 3 points. During the follow-up period, 162(46 %) patients had a significant TMSE decline. Patients with age-adjusted prominent MTA had a significantly shorter TMSE-decline free interval than those without (43.4 ± 4.5 months vs. 68.2 ± 9.5 months, log rank test p-value =0.001). However, the severity of WMH does not significantly influence cognitive outcomes. Cox regression analysis identified that younger age at the time of starting ChEI (p

Limited research has investigated the effects of executive dysfunction on semantic memory deterioration among patients with amnestic mild cognitive impairment (aMCI). This study examined the cognitive performance of 181 participants from various MCI subgroups, a group of mildly impaired individuals with dementia of the Alzheimer type (DAT) and a group of individuals with subjective memory impairment on various semantic memory tasks. The aMCI-single domain (aMCI-sd) group displayed poor performance on a semantic memory task requiring relatively higher degrees of effortful retrieval, and participants in the aMCI-multiple domain (aMCI-md) group, who also suffered with mild executive dysfunction displayed poor performance on all semantic memory tasks, similar to the DAT group. The nonamnestic MCI (non-a-MCI)-single domain group displayed normal performance across all semantic tasks, whereas the non-a-MCI-multiple domain group displayed a pattern similar to that of the aMCI-sd group. aMCI-sd patients who displayed poor performance on the semantic memory task had higher risk of conversion to DAT, whereas poor performance on tasks requiring relatively less effortful retrieval was associated with higher risk of conversion in the aMCI-md group. Thus, executive function may relate to deterioration of semantic memory retrieval processes. Such patterns of semantic memory impairment could be valuable for characterization of cognitive differences among MCI patients.

Geothermal environments are characterized by dynamic redox and temperature fluctuations inherited from the exposure of deeply-sourced, hot, reducing fluids to low-temperature, oxidizing ambient environments. To investigate whether microbial assemblages shifted in response to the changes of a redox state within acidic hot ponds, we collected three paired water and sediment samples from the Tatun Volcano Group, assessed metabolic roles of community members, and correlated their functional capabilities with geochemical factors along depth. Molecular analyses revealed that Sulfolobus spp., Acidianus spp. and Vulcanisaeta spp. capable of respiring elemental sulfur under oxic and/or low-oxygen conditions were the major archaeal members in planktonic communities. In contrast, obligate anaerobic Caldisphaera spp. dominated over others in bottom-dwelling communities. Bacteria were only detected in one locality wherein the majority was affiliated with microaerophilic Hydrogenobaculum spp. Cluster analyses indicated that archaeal communities associated with sediments tended to cluster together and branch off those with water. In addition, the quantities of dissolved oxygen within the water column were substantially less than those in equilibrium with atmospheric oxygen, indicating a net oxygen consumption most likely catalyzed by microbial processes. These lines of evidence suggest that the segregation of planktonic from bottom-dwelling archaeal assemblages could be accounted for by the oxygen affinities inherited in individual archaeal members. Community assemblages in geothermal ecosystems would be often underrepresented without cautious sampling of both water and sediments.

BACKGROUND AND PURPOSE: ARHSP-TCC is characterized by progressive leg spasticity, ataxia, and cognitive dysfunction. Although mutations in the human SPG11 gene were identified as responsible for ARHSP-TCC, the cerebral fiber integrity has not been assessed systemically. The objective of this study was to assess cerebral fiber integrity and its clinical significance in patients with ARHSP-TCC. MATERIALS AND METHODS: Five patients from 2 families who were clinically and genetically confirmed to have ARHSP-TCC were examined by neuropsychological evaluation and DSI of the brain. We performed voxel-based GFA analysis for global white matter evaluation, tractography-based analysis for tract-to-tract comparisons, and tract-specific analysis of the CST to evaluate microstructural integrity along the axonal direction. RESULTS: The neuropsychological evaluation revealed widespread cognitive decline across all domains. Voxel-based analysis showed global reduction of GFA in the cerebral white matter. Tractography-based analysis revealed a significant reduction of the microstructural integrity in all neural fiber types, while commissure and association fibers had more GFA reduction than projection fibers (P < .00001). Prefrontal and motor portions of the CC were most severely affected among all fiber tracts (P < .00001, P = .018). Tract-specific analysis of the CST validated a “dying-back” phenomenon (R(2) = 0.68, P < .00001). CONCLUSIONS: There was a characteristic gradation in the reduction of microstructural integrity among fiber types and within the CC in patients with the SPG11 mutation. The dying-back process in CST might explain the pathogenic mechanisms for ARHSP-TCC.

Suppressed Digit Span performance has been proposed as an embedded indicator for suboptimal effort detection in neuropsychological evaluations in Western societies, particularly in the USA. However, its effectiveness in Chinese countries remains unexplored. The purposes of this study were first to explore normative Digit Span performance patterns between the Taiwan and American standardization samples, then to examine performances of patients with traumatic brain injury and with psychiatric diseases on the embedded measures (the Digit Span Scaled Score, Vocabulary minus Digit Span difference score, Reliable Digit Span, and the longest string of digits forward and backward) through retrospective data analysis. The normative Digit Span performance differs between the two cultural populations. Although litigating and nonlitigating participants perform differently on these measures, further prospective studies are needed to explore this issue with comprehensive external corroborating validity data.

Given the importance of early detection and intervention for disease management, determining the vulnerable neuropsychological function in patients with early-stage Parkinson's disease (PD) is a priority. Here, we describe the neuropsychological pattern in early-stage PD patients with mild cognitive impairment (PD-MCI) and dementia (PDD) in Taiwanese population. The neuropsychological performance of 94 patients with PD was compared with that of 84 healthy controls (HCs) and available normative data, using a comprehensive neuropsychological assessment including tests of executive, memory, psychomotor speed, attention, visuospatial, and language functions. Our results showed that PD patients performed significantly worse on executive function (i.e., category of card sorting) and psychomotor speed (i.e., processing speed index). Up to 46.8% were classified as PD-MCI and the majority of those having single-domain impairment (68.2%); 9.6% met the consensus diagnostic criteria for PDD. Accordingly, we suggest that early-stage PD patients have cognitive dysfunction predominately in the anterior brain. Further follow-up study to determine how many percent of PD-MCI develop PDD is important. The effect of neurocognitive rehabilitation on executive function is also valuable in the subsequence study.

In recent years, online auction systems such as eBay have been more and more popular. The client-server architecture is usually adopted for the basic architecture of online auction systems. However, the client/server architecture usually causes the problems of bandwidth bottleneck and insufficient storage spaces. Therefore, we propose to replace the client/server architecture of traditional online auction systems to P2P architecture for distributing the loading and storage requirement to peers by sellers and buyers. Also, OpenID is exploited to be integrated into our system so that users do not have to remember multiple accounts and passwords. In this paper, the design of an OpenID integrated P2P auction system is proposed. Also, the comparison of our system design and other related P2P auction systems will be discussed.

Olfactory sensory axons navigate from the nasal cavity to the olfactory bulb and sort from among 1,000 different odorant receptor-expressing types to converge upon the same two or three glomeruli. To achieve this task during development, it is likely that multiple classes of regulatory molecules, including cell adhesion molecules, are involved. Cell adhesion molecules have been shown to be important in controlling axon guidance, fasciculation, and synapse formation. To gain further understanding of the involvement of adhesion molecules in olfactory circuitry development, we examined the dynamic and cell type specific expression of a novel protocadherin, PCDH20, in the olfactory system. PCDH20 is specifically expressed in newly differentiated olfactory sensory neurons and their axons during development. PCDH20 expression is down-regulated in the adult olfactory system, except in a small olfactory sensory neuron population. These small, discrete numbers of PCDH20-positive glomeruli in the adult olfactory bulb are consistently clustered in the ventral-caudal region in both male and female mice. However, adult males have higher numbers of PCDH20-positive glomeruli with a broader distribution, whereas adult females have fewer PCDH20-positive glomeruli with a more restricted distribution. The gender difference in PCDH20 expression may reflect olfactory receptor expression differences for gender-specific social discrimination. J. Comp. Neurol. 507:1076–1086, 2008. © 2007 Wiley-Liss, Inc.

The Taiwan Chelungpu Drilling Project (TCDP) has provided an unprecedented opportunity to reveal a terrestrial subsurface microbial ecosystem that has possibly experienced continuous disturbance by the arccontinental collision since 5 Ma. The drilling penetrated Pliocene-Pleistocene sedimentary rocks to a depth of 2000 meters below the land surface (mbls) and encountered two major fault zones. Sixteen samples retrieved from the drilled cores at depths between 464 to 1451 mbls were examined to characterize microbial community structures through cultivation-based approaches. Cultivation experiments were performed with various media at temperatures ranging from 30 to 50¢XC. The results indicate that fermenters and heterotrophic sulfate reducers, using complex organic carbon, were ubiquitously present in most samples. Acetate-utilizing and H2 ¡Vutilizing sulfate reducers were restricted to shallower intervals along the depth profile. Iron reducers and methanogens were only cultivated in a few shallow samples. Twelve pure strains including 8 fermenters, 3 iron reducers and 1 sulfate reducer originally enriched at 30 or 40¢XC were isolated and identified with 16S rDNA sequence analyses. They were phylogenetically affiliated with Firmicutes, Bacteriodes, Actinobacteria, and Proteobacteria in various degrees of similarity. The presence of metabolism was not correlated with lithology, depth, temperature and the appearance of fracture throughout the core. The ubiquitous appearance of fermentation and organotrophic sulfate reduction suggests that organic carbon sources were readily accessible in this deep terrestrial subsurface environment. These results infer that the foreland sedimentary strata disturbed by tectonic activities over a geological time scale might support a heterotrophy-dominated deep terrestrial subsurface microbial ecosystem.

Rac GTPases act as molecular switch in various morphogenic events. However, the regulation of their activities during the development of multicellular organisms is not well understood. Caenorhabditis elegans rac genes ced-10 and mig-2 have been shown to act redundantly to control P cell migration and the axon outgrowth of D type motoneurons. We showed that ced-10 and mig-2 also control amphid axon outgrowth and amphid dendrite fasciculation in a redundant fashion. Our biochemical and genetic data indicate that unc-73, which encodes a protein related to Trio-like guanine nucleotide exchange factor, acts as a direct activator of ced-10 and mig-2 during P cell migration and axon outgrowth of D type motoneurons and amphid sensory neurons. Furthermore, rac regulators ced-2/crkII and ced-5/dock180 function genetically upstream of ced-10 and mig-2 during axon outgrowth of D type motoneurons and act upstream of mig-2 but not ced-10 during P cell migration. However, neither ced-2/crkII nor ced-5/dock180 is involved in amphid axon outgrowth. Therefore, distinct rac regulators control ced-10 and mig-2 differentially in various cellular processes.