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Objective: To examine the effects of navigation controls and field-of-view modes on cybersickness severity and gait dynamics after cessation of exposure to a virtual environment (VE). Background: The applications of virtual reality are increasing in various fields; however, whether changes in interaction techniques and visual contents could mitigate the potential gait disturbance following VE exposure remains unclear. Method: Thirty healthy adults wore a head-mounted display to complete six sessions of 12-min run-and-gun tasks using different navigation controls (gamepad, head, natural) and field-of-view modes (full, restricted). Forward and backward walking tasks were performed before and after VE exposure. The degrees of cybersickness and presence were evaluated using questionnaires, along with the in-session task performance. Spatiotemporal gait measures and their variabilities were calculated for each walking task. Results: The participants experienced less cybersickness with the head and natural controls than with the gamepad. Natural control, based on matching body movements, was associated with the highest degree of presence and best performance. VE navigation using the gamepad showed reduced cadences and increased stride times during postexposure forward-walking tasks. When the VE was presented via the restricted field-of-view mode, increased gait variabilities were observed from backward-walking tasks after VE exposure. Conclusion: Body movement-based navigation controls may alleviate cybersickness. We observed gait adaptation during both ambulation tasks, which was influenced by the navigation control method and field-of-view mode. Application: This study provides the first evidence for gait adaptation during balance-demanding tasks after VE exposure, which is valuable for designing guidelines for virtual reality interactions. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effects of inflatable mat design on body discomfort, task performance, and musculoskeletal exposures during standing computer work. Twenty-seven healthy adults completed three 2-hour standing trials on different mediums (concrete floor, foam mat, and inflatable mat) on different days in an experimental laboratory. Both mats were associated with reduced discomfort in all lower-body regions and increased typing performance compared to the concrete floor. Perceived discomfort in lower extremities (except thighs) was further alleviated while standing on the inflatable mat than on the foam mat. Use of the inflatable mat led to increased lower-body muscle activity, a flexed lower back, and a wide range of sagittal knee movements. As standing time increased, body discomfort increased, typing accuracy decreased, and there were increased variations in muscle activity and postural movements in the lower body. The inflatable mat shows potential to improve the ergonomic experience during prolonged standing. Practitioner summary: Incorporating standing postures in office-based workplaces can reduce sitting time and may mitigate the health hazards associated with sedentary behaviour. With adequate weight-shifting movements, using an inflatable mat for standing could be an effective way to lessen discomfort and accumulated musculoskeletal strain due to constrained standing, without jeopardising task productivity. Abbreviations: APDF: amplitude probability distribution function. AVR: average rectified value. CI: confidence interval. CMRR: common mode rejection ratio. COP: center of pressure. CV: coefficient of variation. EA: electrical activity. EMG: electromyography. FL: fibularis longus. GM: gluteus medius. LBP: lower back pain. LES: lumbar erector spinae. MVC: maximum voluntary contraction. PD: pain developer. rANOVA: repeated-measures analysis of variance. SOL: soleus. VAS: visual analog scale. WPM: words per minute [ABSTRACT FROM AUTHOR]

This study aimed to determine the effects of virtual keyboard designs and postures on task performance and muscle activity during tablet use. Eighteen healthy adults were randomly assigned to one of three postures (DESK, LAP, BED) to complete six sessions of 60-minute typing on a tablet with three virtual keyboards (STD, WIDE, SPLIT) twice in an experimental laboratory. Keystroke dynamics and muscle activity of the forearm and neck-shoulder regions were measured by electromyography. The split virtual keyboard was found to be associated with faster typing speed (SPLIT vs STD, p =.015; SPLIT vs WIDE, p <.001) and decreased muscle activity of extensor digitorum communis (SPLIT vs STD, p =.021). Lap posture was associated with faster typing speed (p =.018) and higher forearm muscle activity (p <.05). Typing performance decreased (p <.001) with elevated neck extensor muscle activity (p =.042) when the task duration prolonged. The split virtual keyboard showed potential to improve tablet ergonomics under various postures. Practitioner Summary: Tablets have become widely used for a variety of tasks and have gradually expanded into the realm of mobile productivity and education. Adequate designs of virtual keyboards for tablets show the potential for increased task performance and decreased muscle activity pertinent to typing activity and posture constraints imposed by non-traditional work positions. Abbreviations: WPM: words per minute; IKI: inter-key press interval; EMG: electromyography; EDC: extensor digitorum communis; FDS: flexor digitorum superficialis; CES: cervical erector spinae; UT: upper trapezius; EA: electrical activity; MVC: maximum voluntary contraction; APDF: amplitude probability distribution function [ABSTRACT FROM AUTHOR]

Abstract Background The association between sexual function and depression has yet to be examined in a prospective cohort study with prolonged postpartum follow-up. Aim We investigated whether sexual dysfunction predicted depressive symptoms during the 24-month postpartum period and examined the influence of obstetric factors. Methods This prospective 2-year cohort study with repeated measures included 196 participants who were recruited in a medical center in Taipei, Taiwan (2010–2011). Data on participants' personal characteristics, sexual function, and depression symptoms at 4–6 weeks and at 3, 6, 12, and 24 months postpartum were collected and then assessed using the Female Sexual Function Index and the Center for Epidemiologic Studies Depression Scale. Results After adjusting for time and covariates, women with sexual dysfunction had a 1.62-fold (95% confidence interval [CI]: 1.05–2.50-fold) higher estimated odds ratio (OR) for depressive symptoms during the entire 24 months after childbirth than did women without sexual dysfunction. Risk factors for depressive symptoms were a higher pain score (OR: 1.33, 95% CI: 1.13–1.57), a medical condition (OR: 1.65, 95% CI: 1.00–2.73), and severe perineal laceration (OR: 4.67, 95% CI: 1.37–15.92). Sexual satisfaction during the entire 24 months after childbirth (OR: 0.81, 95% CI: 0.70–0.95) and the highest personal income level (OR: 0.33, 95% CI: 0.11–0.99) were factors protecting against higher-scoring depressive symptoms. Conclusions Our study provides robust evidence that sexual dysfunction and poor satisfaction, together with severe perineal laceration, greater pain, and a medical condition, predict depressive symptoms during the 24-month postpartum period. [ABSTRACT FROM AUTHOR]

Background: Increasing evidence suggests that walking while performing a concurrent task negatively influences gait performance. However, it remains unclear how higherlevel cognitive processes and coordination of limb movements are altered in challenging walking environments. This study investigated the influence of cognitive task complexity and walking road condition on the neutral correlates of executive function and postural control in dual-task walking. Methods: Twenty-four healthy young adults completed a series of overground walks with three walking road conditions (wide, narrow, with obstacles) with and without the concurrent n-back working memory tasks of two complexity levels (1-back and 3- back). Prefrontal brain activation was assessed by functional near-infrared spectroscopy. A three-dimensional motion analysis system was used simultaneously to measure gait performance and lower-extremity kinematics. Repeated measures analysis of variance were performed to examine the differences between the conditions. Results: In comparison with standing still, participants showed lower n-back task accuracy while walking, with the worst performance from the road with obstacles. Spatiotemporal gait parameters, lower-extremity joint movements, and the relative changes in oxygenated hemoglobin (HbO) concentration levels were all significantly different across the task complexity and walking path conditions. While dual-tasking participants were found to flex their hips and knees less, leading to a slower gait speed, longer stride time, shorter step length, and greater gait variability than during normal walking. For narrow-road walking, smaller ankle dorsiflexion and larger hip flexion were observed, along with a reduced gait speed. Obstacle negotiation was mainly characterized by increased gait variability than other conditions. HbO levels appeared to be lower during dual-task walking than normal walking. Compared to wide and obstacle conditions, walking on the narrow road was found to elicit a smaller decrement in HbO levels. Conclusion: The current study provided direct evidence that, in young adults, neural correlates of executive function and dynamic postural control tend to be altered in response to the cognitive load imposed by the walking environment and the concurrent task during ambulation. A shift of brain activation patterns between functionally connected networks may occur when facing challenging cognitive-motor interaction. [ABSTRACT FROM AUTHOR]

Purpose: The increase in tablet usage allows people to perform computer work in non-traditional office environments. The aim of this study was to assess the effects of changes in tablet keyboard design on postures of the upper extremities and neck, discomfort, and usability under different usage positions during prolonged touch-typing. Methods: Eighteen healthy participants familiar with touch-screen devices were randomized into three usage positions (desk, lap, and bed) and completed six, 60-minute typing sessions using three virtual keyboard designs (standard, wide, split). Electrogoniometers continuously measured the postures of the wrists, elbow, and neck. Body discomfort and system usability were evaluated by questionnaires before and immediately after each typing session. Results: Separate linear mixed effects models on various postural measures and subjective ratings are conducted with usage position as the between-subject factors, keyboard design and typing duration as the with-in subject factors were conducted. Using the tablet in bed led to more extended wrists but a more natural elbow flexion than the desk position. The angled split virtual keyboard significantly reduced the extent of wrist ulnar deviation than the keyboard with either standard or wide design. However, little difference was observed across the usage position and keyboard design. When the postural data were compared between the middle and end of typing sessions, the wrists, elbow, and neck all exhibited a substantially increased range of joint movements (13% to 38%). The discomfort rating also increased significantly over time in every upper body region investigated. Additionally, the split keyboard design received a higher usability rating in the bed position, whereas participants had more satisfactory experience while using the wide keyboard in the traditional desk setting. Conclusions: Prolonged use of tablets in non-traditional office environments may result in awkward postures in the upper body that may expose users to greater risks of developing musculoskeletal symptoms. Adequate virtual keyboard designs show the potential to alleviate some postural effects and improve the user experience without changing the tablet form factors. [ABSTRACT FROM AUTHOR]

Objective: To examine the correlation of function, quality of life (QOL), and parental impact on developmental delayed children. Methods: Sixty parents of children with developmental delays ( M: F = 36:24, mean age 4 years and 2 months) and 56 parents of age-sex matched typical development children were included. Pediatric Outcomes Data Collection Instrument and Child Health Questionnaire for children, World Health Organization-QOL, Impact on Family Scale, and Hospital Anxiety and Depression Scale for parents were assessed. Results: Functional performance was correlated with physical component of QOL in children (correlation coefficients: 0.7-0.9; p < 0.01), age of children (0.3-0.4; p < 0.05) and parents (0.3; p < 0.05), maternal employment (0.3-0.4; p < 0.05), parental QOL (0.3-0.4; p < 0.01), family impact (−0.3 to −0.5; p < 0.01), and parental emotion (−0.3 to −0.4; p < 0.05). Conclusions: Children who exhibited higher levels of function had higher QOL, as did their parents, and less parental impact. [ABSTRACT FROM AUTHOR]

Background/Purpose: Poor oral-motor developments in premature infants are common. From the viewpoint of developmental care, most of the infants required individualized therapy. The specific aim of our study was to evaluate the effectiveness and impact of early intervention of oral-motor management on feeding pattern and the neonatal outcomes in premature neonates. Methods: The study enrolled 68 preterm infants with birth weight less than 1500g or gestational age less than 32 weeks. We tried to strengthen the sucking ability of infants with poor oral-motor coordination. Results: There were significant differences in the body weight (g) while feeding up to 45 mL (1916 ± 156 vs. 2003 ± 191g, p = 0.002) and hospital stay (46.3 ± 25.3 vs. 54.7 ± 23.5 days, p = 0.003) between the study and control groups. Conclusion: Abnormal brain sonography [odds ratio (OR): 2.222, p = 0.047) and necrotizing enterocolitis (NEC) (OR: 2.857, p = 0.017) did affect the first trial in the study group. Early intervention of oral-motor management in very-low-birth-weight premature infants improved feeding performance and neonatal outcome in terms of shorter hospital days. Abnormal brain image and NEC could interfere with the success rate of initial challenge of transitioning from tube to oral feeding in the study group. [ABSTRACT FROM AUTHOR]

Epileptic encephalopathy with suppression-burst in electroencephalography (EEG) can evolve into a few types of epileptic syndromes. We present here an unusual case of early myoclonic encephalopathy that evolved into migrating partial seizures in infancy. A female neonate initially had erratic myoclonus movements, hiccups, and a suppression-burst pattern in EEG that was compatible with early myoclonic encephalopathy. The seizures were controlled with dextromethorphan (20 mg/kg), and a suppression-burst pattern in EEG was reverted to relatively normal background activity. However, at 72 days of age, alternating focal tonic seizures, compatible with migrating partial seizures in infancy, were demonstrated by the 24-hour EEG recording. The seizures responded poorly to dextromethorphan. To our knowledge, this is the first reported case of early myoclonic encephalopathy evolving into migrating partial seizure in infancy. Whether it represents another age-dependent epilepsy evolution needs more clinical observation. [ABSTRACT FROM AUTHOR]

Recently, physiologic sampling pumps (PSPs), which can adjust their sampling rates in proportion to wearers’ minute ventilation (VE), have been proposed to better estimate exposure to airborne contaminants in the workplace. A laboratory evaluation was conducted to compare the performance of a new PSP with a traditional sampling pump (TSP) in an exposure chamber. Fifteen subjects (aged 19–36 years) performed two replicate sessions of step-tests for correlated and uncorrelated exposure scenarios on four separate days. When exposed to a scenario in which subject VEis highly correlated with m-xylene concentration over the sampling period (r= 0.93), the PSP-measured time-weighted average (TWA) concentrations are higher than TSP-measured concentrations (average ratio of PSP to TSP = 1.18). The ratio of PSP- and TSP-measured TWA concentrations for the uncorrelated scenario (r= 0.02) is closer to one, as expected, with an average value of 0.94. The test results of the linear mixed model further indicate that the performance of the PSP is unaffected by the anthropometric and physiological characteristics of the wearer. Potential differences in exposure estimates resulting from the use of the two instruments were examined in light of various schemes which can potentially occur in the field. With the capability of estimating the total volume of air inhaled over the sampling period with improved accuracy, PSPs show promise in reducing the inherent uncertainty in current risk assessment approaches that entail constant-flow (TSP) sampling approaches. [ABSTRACT FROM AUTHOR]

Background/purpose: Chorioamnionitis (CAM) is one of the main causes of preterm labor. The specific aim of our study was to evaluate neonatal outcome and anthropometric growth at the corrected age of 2 years after exposure to an adverse intrauterine event of CAM in very low birth weight (VLBW, less than 1500 g) infants.Methods: One hundred and nineteen VLBW infants had adequate placental histological data available for the study. Maternal and perinatal characteristics and neonatal morbidity were determined. The infants were followed up prospectively and their anthropometric growth was recorded in the neonatal follow-up clinic for 2 years.Results: Histological CAM was evident in 64 cases (53.8%, CAM group). Patients with histological CAM delivered earlier (27.8 +/- 2.9 vs. 29.6 +/- 3.6 weeks, p = 0.003), and they had higher incidence of preterm premature rupture of membranes (PPROM, p less than 0.001) and longer ventilation days (p = 0.001). After adjusting for gestational age, sepsis (aOR, 3.355), bronchopulmonary dysplasia (aOR, 3.018) and mechanical ventilation (aOR, 4.094) had a higher incidence in the CAM group. At the corrected ages of 6, 12, 18 and 24 months, anthropometric measurements, including body weight, body height and head circumference, were similar for the study and control infants.Conclusion: Histological CAM was associated with a higher incidence of PPROM, sepsis, bronchopulmonary dysplasia, more mechanical ventilation and longer ventilation days. However, at the age of 2 years, CAM had no impact on anthropometric growth. [ABSTRACT FROM AUTHOR]

The objectives of this study were to quantify the electromyographic activities (EMG) of finger muscles during prolonged, low-forces, and repetitive typing with an ergonomically designed VDT workstation, as well as to analyze the occurrence and the possible mechanisms of muscular fatigue in touched typists. Thirty healthy female typists were recruited to type consecutively for 2 h. The surface EMG of extensor digitorum communis (EDC) and flexor digitorum superficialis (FDS) of both hands was recorded throughout the entire test. Electrical activity (EA) and median frequency (MDF) were calculated, and then regressed against the time courses to obtain the slopes of progress. Further analysis of the EMG parameters was done by the joint analysis of spectra and amplitudes (JASA). The results indicated that maximum voluntary electrical activation (MVE) decreased after 2-h typing, and did not recover to the initial values even after a 10-min break. Besides, there was a trend of decrement in frequency throughout the entire trail, and the MDF reduced by 25% in comparison with the initial values. With the JASA plot, 74% of the muscles manifested fatigue after 2-h typing activity. Furthermore, we observed that the EDC muscles were more susceptible to muscular fatigue than the FDS muscles. In conclusion, prolonged consecutive typing may induce muscular fatigue in the healthy typists even in an ergonomic typing environment. [Copyright &y& Elsevier]

Limbic encephalitis (LE) is a rare cause of encephalitis presenting as an acute and subacute onset of neuropsychiatric manifestations, particularly with memory deficits and confusion as core features, along with seizure occurrence, movement disorders, or autonomic dysfunctions. LE is caused by neuronal antibodies targeting the cellular surface, synaptic, and intracellular antigens, which alter the synaptic transmission, especially in the limbic area. Immunologic mechanisms involve antibodies, complements, or T-cell-mediated immune responses in different degree according to different autoantibodies. Sensitive cerebrospinal fluid markers of LE are unavailable, and radiographic findings may not reveal a typical mesiotemporal involvement at neurologic presentations; therefore, a high clinical index of suspicions is pivotal, and a neuronal antibody testing is necessary to make early diagnosis. Some patients have concomitant tumors, causing paraneoplastic LE; therefore, tumor survey and treatment are required in addition to immunotherapy. In this study, a review on the molecular and immunologic aspects of LE was conducted to gain awareness of its peculiarity, which we found quite different from our knowledge on traditional psychiatric illness. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the association of blood lead, mercury, and cadmium concentrations with developmental delays and to explore the association of these concentrations with the health status of children. This study recruited 89 children with developmental delays and 89 age- and sex-matched children with typical development. Their health status was evaluated using the Pediatric Quality of Life (PedsQL) Inventory for health-related quality of life (HRQOL) and the Pediatric Outcomes Data Collection Instrument for function. Family function was also evaluated. Blood lead, mercury, and cadmium concentrations were measured using inductively coupled mass spectrometry. The children with developmental delays had a considerably poorer HRQOL, lower functional performance and family function, and a higher blood lead concentration than those with typical development. The blood lead concentration had a significantly positive association with developmental delays [odds ratio (OR) = 1.54, p < 0.01] in a dose-response manner, and it negatively correlated with PedsQL scores (regression coefficient: −0. 47 to −0.53, p < 0.05) in all the children studied. The higher blood cadmium concentration showed a significantly positive association with developmental delays (OR = 2.24, for >1.0 μg/L vs. <0.6 μg/L, p < 0.05). The blood mercury concentration was not associated with developmental delays and health status. [ABSTRACT FROM AUTHOR]

This case-control study identified the association between the arsenic methylation capacity and developmental delays and explored the association of this capacity with the health status of children. We recruited 120 children with developmental delays and 120 age- and sex-matched children without developmental delays. The health status of the children was assessed using the Pediatric Quality of Life Inventory (PedsQL) and Pediatric Outcomes Data Collection Instrument (PODCI). The arsenic methylation capacity was determined by the percentages of inorganic arsenic (InAs%), monomethylarsonic acid (MMAV%), and dimethylarsinic acid (DMAV%) through liquid chromatography and hydride generation atomic absorption spectrometry. Developmental delays were significantly positively associated with the total urinary arsenic concentration, InAs%, and MMAV%, and was significantly negatively associated with DMAV% in a dose-dependent manner. MMAV% was negatively associated with the health-related quality of life (HRQOL; −1.19 to −1.46, P < 0.01) and functional performance (−0.82 to −1.14, P < 0.01), whereas DMAV% was positively associated with HRQOL (0.33-0.35, P < 0.05) and functional performance (0.21-0.39, P < 0.01-0.05) in all children and in those with developmental delays. The arsenic methylation capacity is dose-dependently associated with developmental delays and with the health status of children, particularly those with developmental delays. [ABSTRACT FROM AUTHOR]

Abstract Inefficient arsenic methylation capacity has been associated with developmental delay in preschool children. Selenium has antioxidant and anti-inflammatory properties that protect experimental animals from chemically induced neurotoxicity. The present study was designed to explore whether plasma selenium levels affects arsenic methylation capacity related to developmental delay in preschool children. A case-control study was conducted from August 2010 to March 2014. All participants were recruited from the Shin Kong Wu Ho-Su Memorial Teaching Hospital. In total, 178 children with a developmental delay and 88 children without a delay were recruited. High-performance liquid chromatography-linked hydride generator and atomic absorption spectrometry were used to determine urinary arsenic species, including arsenite (AsIII), arsenate (AsV), monomethylarsonic acid (MMAV), and dimethylarsinic acid (DMAV). Plasma selenium levels were measured by inductively coupled plasma mass spectrometry. As results, plasma selenium concentration was significantly inversely associated with the odds ratio (OR) of developmental delay. Plasma selenium concentration was positively associated with arsenic methylation capacity [percentage of inorganic arsenic and percentage of MMAV (MMAV%) decreased, and percentage of DMAV (DMAV%) increased]. High plasma selenium concentration and high DMA% significantly and additively interacted to decrease the OR of developmental delay; the OR and 95% confidence interval were 0.40 (0.18–0.90). This is the first study to show a combined dose-response effect of plasma selenium concentration and that efficient arsenic methylation capacity decreased the OR of developmental delay in preschool children. Highlights • Plasma selenium concentration was significantly inversely associated with the odds ratio of developmental delay. • Increases in plasma selenium concentration increased the arsenic methylation capacity. • High plasma selenium concentration and high DMA% significantly and additively interacted to decrease the OR of developmental delay. [ABSTRACT FROM AUTHOR]

Inefficient arsenic methylation capacity has been associated with developmental delay in children. The present study was designed to explore whether polymorphisms and haplotypes of arsenic methyltransferase ( AS3MT ), glutathione-S-transferase omegas ( GSTOs ), and purine nucleoside phosphorylase ( PNP ) affect arsenic methylation capacity and developmental delay. A case-control study was conducted from August 2010 to March 2014. All participants were recruited from the Shin Kong Wu Ho-Su Memorial Teaching Hospital. In total, 179 children with developmental delay and 88 children without delay were recruited. Urinary arsenic species, including arsenite (As III ), arsenate (As V ), monomethylarsonic acid (MMA V ), and dimethylarsinic acid (DMA V ) were measured using a high-performance liquid chromatography-linked hydride generator and atomic absorption spectrometry. The polymorphisms of AS3MT , GSTO , and PNP were performed using the Sequenom MassARRAY platform with iPLEX Gold chemistry. Polymorphisms of AS3MT genes were found to affect susceptibility to developmental delay in children, but GSTO and PNP polymorphisms were not. Participants with AS3MT rs3740392 A/G + G/G genotype, compared with AS3MT rs3740392 A/A genotype, had a significantly lower secondary methylation index. This may result in an increased OR for developmental delay. Participants with the AS3MT high-risk haplotype had a significantly higher OR than those with AS3MT low-risk haplotypes [OR and 95% CI, 1.59 (1.08–2.34)]. This is the first study to show a joint dose-response effect of this AS3MT high-risk haplotype and inefficient arsenic methylation capacity on developmental delay. Our data provide evidence that AS3MT genes are related to developmental delay and may partially influence arsenic methylation capacity. [ABSTRACT FROM AUTHOR]

Abstract: Environmental exposure to lead or mercury can cause neurodevelopmental damage. Arsenic is another neurotoxicant that can affect intellectual function in children. This study was designed to explore the difference of arsenic methylation capacity indices between with and without developmental delay in preschool children. We also aimed to identify whether blood levels of lead or mercury modify the effect of arsenic methylation capacity indices. A cross sectional study was conducted from August 2010 to March 2012. All participants recruited from the Shin Kong Wu Ho-Su Memorial Teaching Hospital. In all, 63 children with developmental delay and 35 children without developmental delay were recruited. Urinary arsenic species, including arsenite (AsIII), arsenate (AsV), monomethylarsonic acid (MMAV) and dimethylarsinic acid (DMAV) were measured with a high-performance liquid chromatography-linked hydride generator and atomic absorption spectrometry. Lead and mercury levels of red blood cells were measured by inductively coupled mass spectrometry. All participants underwent developmental assessments to confirm developmental delays, including evaluations of gross motor, fine motor, speech-language, cognition, social, and emotional domains. Urinary total arsenic and MMAV percentage were significantly positively associated and DMAV percentage was negatively associated with the risk of developmental delay in a dose-dependent manner after adjustment for blood lead or mercury levels and other risk factors. A multivariate regression analysis indicated that blood lead level and arsenic methylation capacity each independently contributed to the risk of developmental delay. This is the first study to show that arsenic methylation capacity is associated with developmental delay, even without obvious environmental arsenic exposure. [Copyright &y& Elsevier]

Limbic encephalitis (LE) is a rare cause of encephalitis presenting as an acute and subacute onset of neuropsychiatric manifestations, particularly with memory deficits and confusion as core features, along with seizure occurrence, movement disorders, or autonomic dysfunctions. LE is caused by neuronal antibodies targeting the cellular surface, synaptic, and intracellular antigens, which alter the synaptic transmission, especially in the limbic area. Immunologic mechanisms involve antibodies, complements, or T-cell-mediated immune responses in different degree according to different autoantibodies. Sensitive cerebrospinal fluid markers of LE are unavailable, and radiographic findings may not reveal a typical mesiotemporal involvement at neurologic presentations; therefore, a high clinical index of suspicions is pivotal, and a neuronal antibody testing is necessary to make early diagnosis. Some patients have concomitant tumors, causing paraneoplastic LE; therefore, tumor survey and treatment are required in addition to immunotherapy. In this study, a review on the molecular and immunologic aspects of LE was conducted to gain awareness of its peculiarity, which we found quite different from our knowledge on traditional psychiatric illness.

Associated abnormalities of the white matter in patients with agyria-pachygyria complex have rarely been investigated using new imaging modalities like diffusion tensor imaging. The present study evaluated the white matter changes of 9 children with agyria-pachygyria complex using diffusion tensor imaging. Regions of interest were placed in 17 white matter tracts. Compared with normal controls, the axial diffusivity of the genu of the corpus callosum, corticospinal tract, and fornix in patients with agyria-pachygyria complex was decreased. In the subcortical white matter without changes in T2-weighted image, there were significant decreases in fractional anisotropy and axial diffusivity and increases in radial diffusivity, indicating significant alterations of the white matter. Since axial diffusivity and radial diffusivity reflect changes in the axon and myelin, respectively, the findings here indicate disturbance in both axonal and myelin development in agyria-pachygyria complex.

The merits of using physiologic sampling pumps (PSPs) instead of using constant-flow sampling pumps, i.e., "traditional sampling pumps" (TSPs), are discussed. A novel PSP that overcomes shortcomings of previous PSP designs is presented. Calibrated valves are used to obviate pump inertia that has limited the system response and accuracy of prior work. Technologies that provide minute ventilation (V[combining dot above](E)) of subjects in real time may therefore be used to the limit of their own accuracies to sample inhalation exposures. Analysis of the design and data from a prototype are presented to show how air sampling can be modulated to follow breathing.

A study was conducted to evaluate a portable respiratory inductive plethysmograph (RIP) as a means to estimate minute ventilation (V(E)) for use in controlling the flow rate of a physiologic sampling pump (PSP). Specific aims were to: (1) evaluate the ability of the portable RIP system to measure V(E) using a direct (individual) fixed-volume calibration method (Direct RIP model), (2) develop and evaluate the performance of indirect (group) regression models for V(E) prediction using output data from the portable RIP and subject demographic characteristics (Indirect RIP model), and (3) compare V(E) estimates from indirect and direct portable RIP calibration with indirect estimation models published previously. Nine subjects (19-44 years) were divided into calibration (n = 6) and test (n = 3) datasets and performed step-tests on three different days while wearing the portable RIP and breathing through a pneumotachometer (reference). Minute ventilation and portable RIP output including heart rate, breathing rate, and a motion index were recorded simultaneously during the 80 minute sessions. Calibration data were used to develop a regression model for V(E) prediction that was subsequently applied to the test dataset. Direct calibration of the portable RIP system produced highly variable estimates of V(E) (R2 = 0.62, average % error = 15 +/- 50) while Indirect RIP model results were highly correlated with the reference (R2 = 0.80-0.88) and estimates of total volume were within 10% of reference values on average. Although developed from a limited dataset, the Indirect RIP model provided an alternative approach to estimation of V(E) and total volume with accuracy comparable to previously published models.

Background: Chorioamnionitis (CAM) is one of the main causes of preterm labor and has been associated with an adverse perinatal outcome in preterm infants., Objective: The specific aim of our study was to evaluate whether there is significant difference in the Bayley developmental index scores at 6, 12, 18 and 24 months of corrected age for very-low-birthweight (birth body weight <1500 gm, VLBW) infants with or without placental CAM., Methods: Ninety-five cases (54 in CAM and 41 in non-CAM groups) available for the study were all VLBW infants with adequate histologic placental material for analysis. Neonatal characteristics and morbidities were recorded. The infants were followed up prospectively with Bayley Scales of Infant Development in the Neonatal Follow-up Clinic for 2 years., Results: We found that 56.8% of placentas presented a picture of CAM. In comparison of the neonatal characteristics, VLBW infants with CAM had shorter gestational age (27.9 +/- 2.8 vs. 30.0 +/- 3.7 weeks, p = 0.003), lower Cesarean delivery rate (48.1% vs. 73.2%, p = 0.011), more maternal steroid use (44.4% vs. 12.2%, p = 0.004) and higher incidence of preterm premature rupture of membrane (PPROM, 37.0% vs. 12.2%, p = 0.009). In comparison of neonatal outcomes, the CAM group had higher incidence of bronchopulmonary dysplasia (BPD, 40.7% vs. 19.5%, p = 0.044), more mechanical ventilation (87.0% vs. 27/41, p = 0.023) and intubation (68.5% vs. 46.3%, p = 0.049), and more median days of ventilation (23.1 +/- 29.1 vs. 7.8. +/- 13.7 days, p = 0.001). As for the follow-up, at any test age, either the mean (Mental Development Index (MDI) / (Psychomotor Development Index (PDI) scores of Bayley test or the incidence of score below 85, there was no significant difference in both groups., Conclusions: The VLBW infants with histologic chorioamnionitis were not associated with an increased risk of lower MDI or PDI scores at the corrected ages of 6, 12, 18 and 24 months compared with the non-CAM control group.

Background: The aim of this retrospective study was to assess neonatal outcomes of pregnant women with myasthenia gravis (MG)., Methods: Pregnant women with MG who were treated in our hospital over an 8-year period were enrolled. Data relating to the course of the mother's MG (including the anti-acetylcholine receptor antibody (anti-AchR) titer and drug dosage), delivery mode, delivery course, puerperium period, and neonatal outcomes were obtained from the medical records., Results: Twelve women with MG had 13 pregnancies in our hospital from January 1997 to December 2005. None of the mothers needed intensive care. Two patients delivered vaginally, and ten delivered by cesarean section. Fourteen infants were born at an average gestational age of 37.2 +/- 2.0 weeks; their average birth weight was 2838.6 +/- 724.2 g. Two neonates (14.2%) had a congenital anomaly. Transitory neonatal myasthenia gravis (NMG) was diagnosed in one infant (7.1%)., Conclusions: In our study, MG exacerbations occurred in 38.5% of the patients. Postpartum, all MG patients experienced deterioration except one patient who deteriorated in the first trimester with a concomitant upper airway tract infection. Only 1 of the 14 neonates developed transient NMG; the incidence of transient NMG was lower than that previously reported. There was no correlation between the occurrence of NMG and the maternal anti-AChR titer. The cesarean section rate was approximately 33%; this high rate of elective cesarean sections in these MG patients could have prevented the occurrence of some of the complications related to vaginal delivery.

Background: Quality of life (QOL) is now considered to be an important part of the assessment of dialysis patients. The aim of this study was to develop and assess the reliability, validity and sensitivity of the dialysis module of the World Health Organization Quality of Life - Brief (WHOQOL-BREF) Taiwan version [WHOQOL-BREF(TW)] in patients undergoing regular hemodialysis (HD)., Methods: QOL survey was administered to 283 regular HD patients in metropolitan Taipei. The instruments used included: (1) the proposed module - composed of the core part, the WHOQOL-BREF(TW), and the six specific items; (2) the symptom/problem (S/P) scale - composed of 12 items specific for dialysis patients; (3) the utility measure, which was performed with standard gamble (SG) methods; and (4) the rating scale (RS)., Results: Based on the six criteria of validity, reliability and variance of the items, four HD-specific items were selected. Reliability study showed that Cronbach's alphas, composite reliability, and test-retest reliability (intraclass correlation at an average retest interval of 4-8 weeks) of the four domains of physical, psychological, social relationship and environment, ranged from 0.74-0.82, 0.79-0.84 and 0.61-0.79, respectively. Validity study showed that all the correlations between an item and its corresponding domain were highly significant (r>0.4, p<0.01) and larger than the correlations between the item and other domains. SG and psychometric measures showed relatively low correlations (0.12-0.26). The module showed the same construct as the WHOQOL-BREF(TW) under confirmatory factor analysis, whereas the exploratory factor analysis showed mild variation. Convergent and discriminant validity were good. Global QOL, physical, psychological and environment domains had some sensitivity to differentiate the severity of the condition of patients receiving HD. Clinical validity was demonstrated in global QOL, physical and psychological domains to have significant correlations with S/P scores., Conclusion: Besides broader coverage than the core WHOQOL-BREF(TW), the dialysis module of the WHOQOL-BREF(TW) is a valid, reliable and sensitive QOL instrument for the assessment of HD patients in Taiwan.

Background: In 1991, the World Health Organization (WHO) initiated a cross-cultural project to develop a quality-of-life (QOL) questionnaire (WHOQOL); soon after this, the clinically applicable short form was developed and named WHOQOL-BREF, followed by a Taiwanese version (WHOQOL-BREF[TW])., Methods: We first administered the WHOQOL-BREF(TW) and symptom/problem scale to 376 patients with end-stage renal disease on regular hemodialysis therapy in Taiwan. Analysis with multiple stepwise regressions was conducted to study determinants of QOL domains and items., Results: The WHOQOL-BREF(TW) was reliable and valid from various validation studies. The 4 domains (physical, psychological, social relations, and environment) and global items (overall quality of life and general health) of the WHOQOL-BREF(TW) each differentiated symptoms/problems of hemodialysis patients from age-, sex-, and education-matched healthy referents. The 4 domains, except for environment and global items of the WHOQOL-BREF(TW), each differentiated erythropoietin dosage from age-, sex-, and education-matched healthy referents. After adjusting for age, sex, marriage, and education, the prominent associated factors of various QOL domains and items were age, area (Taipei or Keelung), hemoglobin level, normalized protein catabolic rate, and symptom/problem scale., Conclusion: The WHOQOL-BREF(TW) is reliable and valid for long-term study of hemodialysis patients, and hemodialysis had negative impacts on QOL, especially in patients with more severe disease with greater symptom/problem scores, lower hemoglobin levels, and lower normalized protein catabolic rates.