A Microfluidic System for Stable and Continuous EEG Monitoring from Multiple Larval Zebrafish.

Along with the increasing popularity of larval zebrafish as an experimental animal in the fields of drug screening, neuroscience, genetics, and developmental biology, the need for tools to deal with multiple larvae has emerged. Microfluidic channels have been employed to handle multiple larvae simultaneously, even for sensing electroencephalogram (EEG). In this study, we developed a microfluidic chip capable of uniform and continuous drug infusion across all microfluidic channels during EEG recording. Owing to the modular design of the microfluidic channels, the number of animals under investigation can be easily increased. Using the optimized design of the microfluidic chip, liquids could be exchanged uniformly across all channels without physically affecting the larvae contained in the channels, which assured a stable environment maintained all the time during EEG recording, by eliminating environmental artifacts and leaving only biological effects to be seen. To demonstrate the usefulness of the developed system in drug screening, we continuously measured EEG from four larvae without and with pentylenetetrazole application, up to 60 min. In addition, we recorded EEG from valproic acid (VPA)-treated zebrafish and demonstrated the suppression of seizure by VPA. The developed microfluidic system could contribute to the mass screening of EEG for drug development to treat neurological disorders such as epilepsy in a short time, owing to its handy size, cheap fabrication cost, and the guaranteed uniform drug infusion across all channels with no environmentally induced artifacts.

An EEG system to detect brain signals from multiple adult zebrafish.

Zebrafish has been widely used as an experimental animal in many biological processes to study brain functions, neurological disorders and drug toxicity. Electroencephalogram (EEG), which directly measures brain activities, has been used to diagnose and study neurological disorders. Previous studies have recorded EEG signals from adult zebrafish, but the recordings have been only possible from a single individual. In this study, we developed a system to record EEG of multiple adult zebrafish simultaneously. To secure multiple zebrafish in a stable condition for a certain time, perfusion and recording systems were mechanically separated, which allowed effective immobilization of the fish. We recorded EEG signals from pentylenetetrazole (PTZ)-induced seizure models and valproic acid (VPA)-treated models to demonstrate the performance of the developed system in validation of the effect of anti-epileptic drugs. The developed system effectively measured individual EEG signals from more than three zebrafish out of four simultaneously on average. Seizure induction by PTZ and seizure suppression by VPA were successfully detected through EEG recording. The scheme of the EEG recording system developed in this study has a potential for expansion and could be further applied to mass drug screening in a short time.

Measurements of morphology and refractive indexes on human downy hairs using three-dimensional quantitative phase imaging.

We present optical measurements of morphology and refractive indexes (RIs) of human downy arm hairs using three-dimensional (3-D) quantitative phase imaging techniques. 3-D RI tomograms and high-resolution two-dimensional synthetic aperture images of individual downy arm hairs were measured using a Mach­Zehnder laser interferometric microscopy equipped with a two-axis galvanometer mirror. From the measured quantitative images, the RIs and morphological parameters of downy hairs were noninvasively quantified including the mean RI, volume, cylinder, and effective radius of individual hairs. In addition, the effects of hydrogen peroxide on individual downy hairs were investigated.

A case of incidentally discovered subclinical cushing syndrome in a patient with chronic fatigue and anxiety.

Subclinical Cushing syndrome (SCS) is a hypothalamic-pituitary-adrenal axis abnormality characterized by autonomous cortisol secretion in patients with no typical signs or symptoms of Cushing syndrome. SCS patients may have adverse metabolic and cardiovascular effects due to slight, but continuous glucocorticoid secretion. Glucocorticoids also affect behavior, mood, neural activity, and a number of specific biochemical processes in the central nervous system. Here, we report a case of SCS due to an adrenal incidentaloma in a hypertensive diabetic patient who presented with chronic fatigue and anxiety that disappeared after the removal of the adrenal adenoma.

Effect of Korean red ginseng on insulin sensitivity in non-diabetic healthy overweight and obese adults.

BACKGROUND: Korean red ginseng is one of the most popular herbs worldwide due to the belief that it contains ingredients that possess a variety of health enhancing effects including anti-diabetic effects. The objective of this study was to determine whether Korean red ginseng supplement has an effect on insulin sensitivity in healthy overweight or obese adults without overt diabetes and hypertension. METHODS: In a double-blinded, placebo controlled, randomized trial, a total of 68 participants (BMI >=23 kg/m2) received either 6 g of Korean red ginseng rootlets (n=34) or a placebo each day over a 12 week period. RESULTS: Similar insulin levels and insulin sensitivity index were observed at baseline in the Korean red ginseng and control groups. Korean red ginseng had no significant effect on improving the insulin sensitivity over time. Korean red ginseng does not improve the insulin sensitivity of overweight and obese subjects who do not have diabetes or hypertension.

Changes in skin color after smoking cessation.

This study was performed to assess changes in skin color over 1 month after smoking cessation. The study population consisted of 49 men who participated in a smoking cessation program from March 2010 to June 2010 at a public health centre in Yangsan, South Korea. Thirty-four men who stop smoking completely were included in our study. Instrumental evaluations of skin color were performed using Mexameter (MX 18; Courage and Khazaka Electronic GmbH) at the beginning of the study and at 1-week and 4-week follow-up visits. Skin color was evaluated by measurement of 2 main color bases-melanin and haemoglobin-with the results expressed as melanin index (MI) and erythema index (EI). Both MI and EI were significantly reduced at the 4-week follow-up visit on all 7 sites measured. We anticipate that desirable effects on skin color after smoking cessation will play a positive role in maintaining smoking abstinence in routine clinical practice.

A Case of Wilson's Disease in Patient with Mildly Elevated Liver Enzymes.

Wilson's disease is an autosomal recessive disorder affecting copper transport; it results in the accumulation of copper in the liver, brain, and other organs. Wilson's disease is the most common inherited liver disease with more than 500 cases reported in Korea. An impairment in biliary excretion process leads to copper accumulation in the liver, which progressively damages the liver, leading to cirrhosis. Since effective treatment is available for this disease, early and correct diagnosis is very important. Here, we report a case of Wilson's disease with mildly elevated liver enzyme levels in a 29-year-old breast-feeding woman with weight loss.

The effectiveness of implementing a bladder ultrasound programme in neurosurgical units.

AIM: This paper reports an evaluation of the differences among rates of unnecessary catheterization, urinary retention and urinary tract infection before and after implementing a bladder ultrasound programme to assess urine volume. BACKGROUND: Bladder ultrasound is a non-invasive alternative to urethral catheterization for the determination of bladder urine volume. Much of the literature available on bladder ultrasound technology addresses the accuracy of the equipment, with little research on the clinical outcomes or benefits of the intervention. METHODS: A quasi-experimental design was adopted. Data were collected from March 2001 to May 2001 in a control group in two neurosurgical units in Taiwan. During July and August 2001, nurses were taught how to operate a portable ultrasound machine and how to implement the programme. Data were collected from September to November 2001 in the study group. RESULTS: The rates of unnecessary catheterization in the control group and the study group were 35.3% and 7.0%, respectively. The urine volume (more than 500 mL) in the control group and the study group were 13.4% and 20.3%, respectively. The study group had a statistically significantly lower average catheterization volume than that of the control group (676.9 mL vs. 777.1 mL, t = 1.84, P < 0.05). During 3 months before and after the implementation of the programme, the urinary tract infection rates in the control group and the study group were 3.47% and 2.87%, respectively. After 6 months the urinary tract infection rates decreased to 1.39%. CONCLUSION: The bladder ultrasound programme was successful and could be used to manage patients with urination disorders in neurosurgical units.