A systematic review and activation likelihood estimation meta-analysis of fMRI studies on arousing or wake-promoting effects in Buddhist meditation.

Conventional Buddhist texts illustrate meditation as a condition of relaxed alertness that must fend against extreme hypoarousal (sleep, drowsiness) and extreme hyperarousal (restlessness). Theoretical, neurophysiological, and neuroimaging investigations of meditation have highlighted the relaxing effects and hypoarousing without emphasizing the alertness-promoting effects. Here we performed a systematic review supported by an activation-likelihood estimate (ALE) meta-analysis in an effort to counterbalance the surfeit of scholarship emphasizing the hypoarousing and relaxing effects of different forms of Buddhist meditation. Specifically, the current systematic review-cum-meta-analytical review seeks to highlight more support for meditation's wake-promoting effects by drawing from neuroimaging research during wakefulness and meditation. In this systematic review and meta-analysis of 22 fMRI studies, we aim to highlight support for Buddhist meditation's wake-promoting or arousing effects by identifying brain regions associated with alertness during meditation. The most significant peaks were localized medial frontal gyrus (MFG) and precuneus. We failed to determine areas ostensibly common to alertness-related meditation such as the medial prefrontal cortex (mPFC), superior parietal lobule, basal ganglia, thalamus, most likely due to the relatively fewer fMRI investigations that used wakefulness-promoting meditation techniques. Also, we argue that forthcoming research on meditation, related to alertness or wakefulness, continues to adopt a multi-modal method to investigate the correlation between actual behaviors and neural networks connected to Buddhist meditation. Moreover, we recommend the implementation of fMRI paradigms on Buddhist meditation with clinically diagnosed participants to complement recent trends in psychotherapy such as mindfulness-based cognitive therapy (MBCT).

Validation of the tablet-administered Brief Assessment of Cognition (BAC App).

Computerized tests benefit from automated scoring procedures and standardized administration instructions. These methods can reduce the potential for rater error. However, especially in patients with severe mental illnesses, the equivalency of traditional and tablet-based tests cannot be assumed. The Brief Assessment of Cognition in Schizophrenia (BACS) is a pen-and-paper cognitive assessment tool that has been used in hundreds of research studies and clinical trials, and has normative data available for generating age- and gender-corrected standardized scores. A tablet-based version of the BACS called the BAC App has been developed. This study compared performance on the BACS and the BAC App in patients with schizophrenia and healthy controls. Test equivalency was assessed, and the applicability of paper-based normative data was evaluated. Results demonstrated the distributions of standardized composite scores for the tablet-based BAC App and the pen-and-paper BACS were indistinguishable, and the between-methods mean differences were not statistically significant. The discrimination between patients and controls was similarly robust. The between-methods correlations for individual measures in patients were r>0.70 for most subtests. When data from the Token Motor Test was omitted, the between-methods correlation of composite scores was r=0.88 (df=48; p<0.001) in healthy controls and r=0.89 (df=46; p<0.001) in patients, consistent with the test-retest reliability of each measure. Taken together, results indicate that the tablet-based BAC App generates results consistent with the traditional pen-and-paper BACS, and support the notion that the BAC App is appropriate for use in clinical trials and clinical practice.

A Micro-Platinum Wire Biosensor for Fast and Selective Detection of Alanine Aminotransferase.

In this study, a miniaturized biosensor based on permselective polymer layers (overoxidized polypyrrole (Ppy) and Nafion(®)) modified and enzyme (glutamate oxidase (GlutOx)) immobilized micro-platinum wire electrode for the detection of alanine aminotransferase (ALT) was fabricated. The proposed ALT biosensor was measured electrochemically by constant potential amperometry at +0.7 V vs. Ag/AgCl. The ALT biosensor provides fast response time (~5 s) and superior selectivity towards ALT against both negatively and positively charged species (e.g., ascorbic acid (AA) and dopamine (DA), respectively). The detection range of the ALT biosensor is found to be 10-900 U/L which covers the range of normal ALT levels presented in the serum and the detection limit and sensitivity are found to be 8.48 U/L and 0.059 nA/(U/L·mm²) (N = 10), respectively. We also found that one-day storage of the ALT biosensor at -20 °C right after the sensor being fabricated can enhance the sensor sensitivity (1.74 times higher than that of the sensor stored at 4 °C). The ALT biosensor is stable after eight weeks of storage at -20 °C. The sensor was tested in spiked ALT samples (ALT activities: 20, 200, 400, and 900 U/L) and reasonable recoveries (70%~107%) were obtained.

Relationship Between Physician Assistant Program Length and Physician Assistant National Certifying Examination Pass Rates.

PURPOSE: This study was conducted to examine the relationship between physician assistant (PA) educational program length and PA programs' 5-year average Physician Assistant National Certifying Examination (PANCE) first-time pass rates. METHODS: This was a retrospective correlational study that analyzed previously collected data from a nonprobability purposive sample of accredited PA program Web sites. Master's level PA programs (n = 108) in the United States with published average PANCE scores for 5 consecutive classes were included. Provisional and probationary programs were excluded (n = 4). Study data were not normally distributed per the Kolmogorov-Smirnov test, P = .00. RESULTS: There was no relationship between program length and PANCE pass rates, ρ (108) = -0.04, P = .68. Further analyses examining a possible relationship between program phase length (didactic and clinical) and PANCE pass rates also demonstrated no differences (ρ [107] = -0.05, P = .60 and ρ [107] = 0.02, P = .80, respectively). CONCLUSION: The results of this study suggest that shorter length PA programs perform similarly to longer programs in preparing students to pass the PANCE. In light of rapid expansion of PA educational programs, educators may want to consider these findings when planning the length of study for new and established programs.

Fabrication of implantable, enzyme-immobilized glutamate sensors for the monitoring of glutamate concentration changes in vitro and in vivo.

Glutamate sensors based on the immobilization of glutamate oxidase (GlutOx) were prepared by adsorption on electrodeposited chitosan (Method 1) and by crosslinking with glutaraldehyde (Method 2) on micromachined platinum microelectrodes. It was observed that glutamate sensors prepared by Method 1 have faster response time (<2 s) and lower detection limit (2.5±1.1 µM) compared to that prepared by Method 2 (response time: <5 sec and detection limit: 6.5±1.7 µM); glutamate sensors prepared by Method 2 have a larger linear detection range (20-352 µM) and higher sensitivity (86.8±8.8 nA·µM-1·cm-2, N=12) compared to those prepared by Method 1 (linear detection range: 20-217 µM and sensitivity: 34.9±4.8 nA·µM-1·cm-2, N=8). The applicability of the glutamate sensors in vivo was also demonstrated. The glutamate sensors were implanted into the rat brain to monitor the stress-induced extracellular glutamate release in the hypothalamus of the awake, freely moving rat.

Implantable Microprobe with Arrayed Microsensors for Combined Amperometric Monitoring of the Neurotransmitters, Glutamate and Dopamine.

An implantable, micromachined microprobe with a microsensor array for combined monitoring of the neurotransmitters, glutamate (Glut) and dopamine (DA), by constant potential amperometry has been created and characterized. Microprobe studies in vitro revealed Glut and DA microsensor sensitivities of 126±5 nA·µM(-1)·cm(-2) and 3250±50 nA·µM(-1)·cm(-2), respectively, with corresponding detection limits of 2.1±0.2 µM and 62±8 nM, both at comparable ~1 sec response times. No diffusional interaction of H(2)O(2) among arrayed microelectrodes was observed. Also, no responses from the electroactive interferents, ascorbic acid (AA), uric acid (UA), DOPA (a DA catabolite) or DOPAC (a DA precursor), over their respective physiological concentration ranges, were detected. The dual sensing microbe attributes of size, detection limit, sensitivity, response time and selectivity make it attractive for combined sensing of Glut and DA in vivo.

Transient extracellular glutamate events in the basolateral amygdala track reward-seeking actions.

The ability to make rapid, informed decisions about whether or not to engage in a sequence of actions to earn reward is essential for survival. Modeling in rodents has demonstrated a critical role for the basolateral amygdala (BLA) in such reward-seeking actions, but the precise neurochemical underpinnings are not well understood. Taking advantage of recent advancements in biosensor technologies, we made spatially discrete near-real-time extracellular recordings of the major excitatory transmitter, glutamate, in the BLA of rats performing a self-paced lever-pressing sequence task for sucrose reward. This allowed us to detect rapid transient fluctuations in extracellular BLA glutamate time-locked to action performance. These glutamate transients tended to precede lever-pressing actions and were markedly increased in frequency when rats were engaged in such reward-seeking actions. Based on muscimol and tetrodotoxin microinfusions, these glutamate transients appeared to originate from the terminals of neurons with cell bodies in the orbital frontal cortex. Importantly, glutamate transient amplitude and frequency fluctuated with the value of the earned reward and positively predicted lever-pressing rate. Such novel rapid glutamate recordings during instrumental performance identify a role for glutamatergic signaling within the BLA in instrumental reward-seeking actions.

A convenient homogeneous enzyme immunoassay for estradiol detection.

A convenient homogeneous enzyme immunoassay for estradiol is described. Unlike heterogeneous immunoassays, which require time-consuming separation steps or expensive automated systems, homogeneous immunoassays, wherein all reagents are freely suspended in bulk solution, can be simple and fast without costly instrumentation. The key component of this assay system, an estradiol-reporter enzyme conjugate, was prepared by covalently binding ß-estradiol-6-(O-carboxymethyl)oxime to glucose-6-phosphate dehydrogenase (G6PDH) by an N-hydroxysuccinimide-enhanced, carbodiimide-mediated coupling reaction. The estradiol-G6PDH activity can be repressed up to 46% upon anti-estradiol antibody binding. The lower detection limit of the assay is 1 nM estradiol in aqueous solution, and the standard curve is linear on logit-log scale-up to 6.7 µM estradiol. A detection limit of 11.5 nM in estradiol-spiked human serum samples suggests the feasibility of applying this assay to monitor estradiol levels for the prediction and prevention of ovarian hyperstimulation syndrome.