Clinical observation on acute low-frequency hearing loss without vertigo: the role of cochlear hydrops analysis masking procedure as initial prognostic parameter.

OBJECTIVES: Even though it is currently not possible to prove a pathological diagnosis for inner ear disease, acute low-frequency hearing loss (ALFHL) without vertigo could be caused by inner ear hydrops because progression into the clinical spectrum of endolymphatic hydrops (EH) frequently occur among patients with the initial clinical presentation. Therefore, audiological measures representative of inner ear hydrops, such as the cochlear hydrops analysis masking procedure (CHAMP) test, may be used to predict the prognosis of ALFHL without vertigo. To test this hypothesis, we prospectively investigated patients with ALFHL unaccompanied by vertigo and examined whether the CHAMP test generated more useful information for prediction of progression into clinical spectrum of EH compared with other neurotologic parameters. DESIGN: A prospective clinical study of 28 patients who initially presented with ALFHL without vertigo was conducted. Detailed neurotologic findings from pure-tone audiometry, electrocochleography, CHAMP, spontaneous nystagmus, head-shaking nystagmus, vibration-induced nystagmus, the bithermal caloric test, and the rotatory chair test were recorded at the time of initial presentation. A regular audiological and clinical examination was conducted until either the last follow-up at our clinic or on the day on which secondary audiovestibular symptoms occurred. The rates of progression to Ménière's disease (MD) or clinical presentation compatible with isolated cochlear hydrops during the study period were calculated by the log-rank test and relative risk. A receiver operating characteristics curve was plotted to determine the prognostic value of CHAMP. RESULTS: Of 28 patients, 15 (53%) showed improvement in hearing on pure-tone audiometry. Seven patients (25%) showed hearing fluctuation and nine (32%) developed a vertigo attack during the observation period. Of these, three patients experienced both vertigo and a hearing fluctuation. Abnormal results of electrocochleography and neurotologic tests reflecting vestibular ocular reflex on yaw plane were common at the time of diagnosis of ALFHL in many patients, but these parameters were not associated with an increased risk of progression of clinical spectrum of EH. In contrast, patients with an abnormal complex amplitude ratio (CAR) on CHAMP had a 2.6-fold increased risk of progression to a clinical spectrum of EH (either hearing fluctuation or MD). The hazard ratio of developing MD for patients with normal CAR as compared with those with an abnormal CAR was 0.137 (95% confidence interval 0.03-0.57; p < 0.001), which indicates an 84.3% reduced risk of developing MD in those with normal CAR. A CAR value of 0.975 or less indicated the possibility of developing either a hearing fluctuation or vertiginous episode with a sensitivity of 82% and a specificity of 73% by receiver operating characteristics curve analysis. CONCLUSIONS: The results of the study suggest that CHAMP measurement may be useful for determining the prognosis of patients with ALFHL without vertigo. A CAR value of 0.975 or less indicates the possibility of developing fluctuating hearing loss or vertigo in patients with ALFHL unaccompanied by vertigo.

Predialysis Urea Nitrogen Is a Nutritional Marker of Hemodialysis Patients.

End-stage renal disease (ESRD) patients on hemodialysis have poor nutritional status and associated problems such as inflammation and sarcopenia. Blood urea nitrogen (BUN) is an important measure of uremic toxins, and urea reduction is a marker of hemodialysis efficacy. However, a low protein diet for lower BUN could aggravate malnutrition in patients, and optimal pre-dialysis BUN is not defined. We investigated the association of pre-dialysis BUN with patients' comorbidities and the relationship between pre-dialysis BUN and serum albumin as a nutrient marker. Among the 67 patients, the average pre- and post-dialysis BUN were 59.2 and 15.0 mg/dL, respectively, serum creatinine was 10.1 mg/dL, and the average serum albumin was 4.0 g/dL. Patients' age was negatively correlated with serum creatinine (r=-0.277, p<0.05) and albumin (r=-0.453, p<0.001). Predialysis BUN showed a significant positive correlation with serum albumin (r=0.287, p<0.05) and creatinine (r=0.454, p<0.001). However, the predialysis BUN was not significantly related to diabetes, coronary artery disease, congestive heart failure, or cerebrovascular disease. Hemodialysis patients with high pre-dialysis BUN and high serum creatinine could be regarded as having good nutritional status. The significance of this study lies in the potential utility of pre-dialysis blood urea nitrogen as an indicator of the nutritional status of patients. Liberal protein intake might be recommended to adequately dialyzed patients.

The Associations Between Vitamin D Receptor BsmI and ApaI Polymorphisms and Obesity in Korean Patients with Type 2 Diabetes Mellitus.

BACKGROUND: Vitamin D receptor (VDR) polymorphisms are associated with osteoporosis, diabetes, immunological diseases, and cancers. However, the association of obesity with VDR polymorphisms has shown inconsistent results, and perhaps it depends upon the characteristics of a population. Therefore, we evaluated the association between BsmI (rs1544410) and ApaI (rs7975232) polymorphisms of VDR and obesity in Korean patients with type 2 diabetes mellitus (T2DM). METHODS: A total of 506 patients with T2DM participated in the study. Polymerase chain reaction-restriction fragment length polymorphism was used to analyze BsmI and ApaI polymorphisms; the genotypes were presented as BB, Bb, or bb for BsmI and AA, Aa, or aa for ApaI. Obesity was defined using the body mass index (BMI) with a cutoff level of 25 kg/m2. RESULTS: The prevalence of obesity was higher in patients with the bb genotype than in those with BB or Bb genotypes (48.4% vs 33.9%, P = 0.031). The mean BMI was 25.2 ± 3.5 kg/m2 in patients with bb genotype and 24.1 ± 3.1 kg/m2 in patients with BB or Bb genotypes. Patients with Aa or aa genotypes showed a higher prevalence of obesity than patients with AA genotype (47.6% vs 26.1%, P = 0.043). Glycemic control parameters and lipid profiles did not show significant differences with either polymorphism. CONCLUSION: To our knowledge, this is the first study to assess the association between VDR polymorphisms and obesity in Korean patients with T2DM. Further studies in larger populations and multiethnic cohorts are needed to validate our findings.

Virtual environment training system for rehabilitation of stroke patients with unilateral neglect: crossing the virtual street.

In this paper, we propose a system for training of stroke patients with unilateral neglect by using technology of virtual reality (VR). The proposed system is designed to compensate for unilateral neglect. This system contains the calibration of unilateral neglect and the training of this disease. The calibration procedure is implemented by aligning the virtual object at a subjective middle line. The training procedure is implemented by completing the missions that are used to keep the virtual avatar safe during crossing the street in a virtual environment. The results of this study show that the proposed system is effective to train unilateral neglect. The left to right ratio scores extracted from this system gradually decrease as the sessions of training are repeated. To validate the VR system parameters, the parameters are analyzed by correlation with those of traditional unilateral neglect assessment methods (such as the line bisection test and the cancellation test).

Pilot study for assessing the behaviors of patients with schizophrenia towards a virtual avatar.

This study examined whether a virtual avatar could be perceived as a real human by patients with mental disease, especially schizophrenia, as well as whether a virtual avatar could be applied to acquiring patients' behavior characteristics in a short conversation situation. The virtual avatar has been used for various applications which need to communicate with other person or to train or educate by showing humanlike behavior. Recently, many researches have shown that the virtual avatar technology has been enhanced and the avatar could be perceived like real human. A virtual avatar, standing in a virtual room, was designed for this study. Tasks to approach, initiate a talk, and answer to avatar's questions was assigned to the 11 patients with schizophrenia. As behavioral parameters in the virtual environment, the interpersonal distance and the verbal response time were acquired. In addition, the Positive and Negative Syndrome Scale (PANSS) for patients was administered in order to investigate the relationship between patients' symptomatic characteristics and behavior parameters. The interpersonal distance was negatively correlated with the negative syndrome scale, a subscale of PANSS, which is consistent with previous research reporting the relationship between interpersonal distance and a real person's image. The verbal response time, however, was not correlated with any other subscale of PANSS. After analyzing subitems of the negative syndrome of PANSS, two positive correlations were found: one was with blunted affect and the other was with poor rapport. We concluded that the virtual avatar could be perceived as a real human by schizophrenic patients and the avatar could draw the schizophrenic patients' behavior characteristics.

Directional disorder of ciliary metachronal waves using two-dimensional correlation map.

The interrelationship of cilia and the order of wave directions are important factors that determine the effectiveness of cilia to transport materials in mucociliary systems of the respiratory tract. The interrelationship of cilia and the directional disorder of ciliary metachronal wave were analyzed using digital microscopic images. The degree of synchronization between ciliary beats was determined by the correlation factor between two different spots. To find out the uniphase directions of beating cilia, principal axes of inertia were applied to the two-dimensional correlation map calculated from sequential ciliary images. The standard deviation of determined wave directions in a region of interest (ROI) was defined as a measure of metachronal wave disorder. The pooled mean of metachronal wave disorder was 23.4 +/- 8.79 degrees in ROIs of 8 microm x 8 microm and 25.4 +/- 6.46 degrees in 32 microm x 24 microm from the sphenoid sinus mucosa of five normal subjects. Our result shows that there is a considerable variation in metachronal wave directions of cilia beating on the epithelium.

Discovery of novel DUSP16 phosphatase inhibitors through virtual screening with homology modeled protein structure.

Recently, dual-specificity phosphatase 16 (DUSP16) emerged as a promising therapeutic target protein for the development of anti-atherosclerosis and anticancer medicines. The present study was undertaken to identify the novel inhibitors of DUSP16 based on the structure-based virtual screening. We have been able to find seven novel inhibitors of DUSP16 through the drug design protocol involving homology modeling of the target protein, docking simulations between DUSP16 and its putative inhibitors with the modified scoring function, and in vitro enzyme assay. These inhibitors revealed good potency, with IC50 values ranging from 1 to 22 µM, and they were also screened computationally for having desirable physicochemical properties as drug candidates. Therefore, they deserve consideration for further development by structure-activity relationship studies to optimize the inhibitory activity against DUSP16. Structural features relevant to the stabilization of the newly identified inhibitors in the active site of DUSP16 are addressed in detail.