Early changes in retinal structure and BMP2 expression in the retina and crystalline lens of streptozotocin-induced diabetic pigs / 한국실험동물학회지

PURPOSE: This study aims to evaluate early changes in retinal structure and BMP2 expression in the retina and crystalline lens by comparing streptozotocin-induced diabetic pigs and normal control group pigs. METHODS: Five eye samples from five diabetic Micro-pigs (Medikinetics, Pyeongtaek, Korea) and five eye samples from five control pigs bred in a specific pathogen-free area were used. Diabetes was developed through intravenous injection of nicotinamide and streptozotocin, and the average fasting glucose level was maintained at 250 mg/dL or higher for 16 weeks. To evaluate BMP2 expression in the retina and crystalline lens, Western blotting was performed. RESULTS: In Hematoxylin and Eosin staining, most diabetic pigs showed structural abnormalities in the inner plexiform layer. The number of nuclei in the ganglion cell layer within the range of 10⁴µm² was 3.78±0.60 for diabetic pigs and 5.57±1.07 for control group pigs, showing a statistically significant difference. In immunohistochemical staining, diabetic retinas showed an overall increase in BMP2 expression. In Western blotting, the average BMP2/actin level of diabetic retinas was 1.19±0.05, showing a significant increase compared to the 1.06±0.03 of the control group retinas (P=0.016). The BMP2/actin level of diabetic crystalline lenses was similar to the control group crystalline lenses (P=0.730). CONCLUSIONS: Compared to control group pigs, the number of nuclei in the inner nuclear layer of retinas from streptozotocin-induced diabetic pigs decreased, while an increase in BMP2 expression was observed in the retina of diabetic pigs.

Diagnostic Ability of Spectral Domain OCT: Comparision between Preperimetric Glaucoma and Large Physiologic Cupping

PURPOSE: To assess the distinction ability for differentiating glaucoma patients based on optic disc, retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) measured using spectral domain optical coherence tomography (SD-OCT). Additionally, the diagnostic ability of these parameters was evaluated by comparing preperimetic glaucoma patients who frequently visited the clinic and normal patients with and without a large physiologic cup/disc (C/D) ratio. METHODS: Using SD-OCT, the optic disc, RNFL and GCIPL of preperimetic glaucoma patients were compared with normal people with and without a large C/D ratio from March, 2011 to December, 2014 at Department of Ophthalmology, Inha University Hospital. Preperimetic glaucoma was defined using the normal standard automated perimetry for glaucomatous optic nerve changes such as asymmetry of vertical C/D ratio, rim thinning, notching, excavation and RNFL defect. RESULTS: When comparing preperimetic glaucoma patients to normal people without large disc cupping, the most reliable parameter for optic disc parameters, vertical C/D ratio (0.89), showed more reliable diagnostic ability than the most reliable parameter for retinal nerve fiber, inferior RNFL thickness (0.79) and superonasal and inferonasal GCIPL thickness were the most reliable GCIPL parameters (p = 0.005 and 0.002, respectively). When comparing preperimetic glaucoma patients to normal people having a large physiologic disc cupping, average C/D ratio among optic nerve parameters, inferior RNFL thickness among RNFL thickness parameters and inferior GCIPL thickness among GCIPL parameters showed highly reliable diagnostic abilities. These 3 parameters were not statistically different (all p > 0.05) and had lower distinction ability than reported in previous studies. CONCLUSIONS: Diagnostic abilities of SD-OCT for distinguishing preperimetric glaucoma from normal people having large physiologic disc cupping were similar for optic disc, RNFL and GCIPL and showed low diagnostic ability than compared to normal people without large disc cupping.

Serum measurements of testosterone, insulin-like growth factor 1, and insulin-like growth factor binding protein-3 in the diagnosis of prostate cancer among Korean men / 亚洲男科学杂志(英文版)

<p><b>AIM</b>To investigate the relationships of serum testosterone, insulin-like growth factor (IGF)-1 and IGF-binding protein (IGFBP)-3 levels with prostate cancer risk and also with known prognostic parameters of prostate cancer in Korean men who received radical retropubic prostatectomy (RRP) for clinically-localized prostate cancer.</p><p><b>METHODS</b>Serum levels of total testosterone, free testosterone, IGF-1 and IGFBP-3 were determined in 592 patients who subsequently received prostate biopsy. Results were compared between patients who eventually received RRP for prostate cancer (n=159) and those who were not diagnosed with prostate cancer from biopsy (control group, n=433). Among the prostate cancer only patients, serum hormonal levels obtained were analyzed in relation to serum prostate specific antigen (PSA), pathological T stage and pathological Gleason score.</p><p><b>RESULTS</b>Prostate cancer patients and the control group demonstrated no significant differences regarding serum levels of total testosterone, free testosterone, IGF-1 and IGFBP-3 across the different age groups. Among the cancer only patients, no significant associations were observed for serum levels of total testosterone, free testosterone, IGF-1 and IGFBP-3 levels with pathological T stage, pathological Gleason score and preoperative PSA.</p><p><b>CONCLUSION</b>Our data indicate that simple quantifications of serum testosterone and IGF-1 along with IGFBP-3 levels might not provide useful clinical information in the diagnosis of clinically localized prostate cancer in Korean men. Also, our results suggest that serum levels of testosterone, IGF-1 and IGFBP-3 might not be significantly associated with known prognostic factors of clinically localized prostate cancer in Korean men.</p>

A Preliminary Study for the Estimation of the First Positive Lyapunov Exponent of the EEG in Experimental Status Epilepticus Rats / 대한간질학회지

BACKGROUND AND OBJECTIVES: The hypothesis that brain is a nonlinear dynamic system exhibiting deterministic chaos has offered new methods to the investigation of information processing in the brain by analysis and classification of EEG signals. We used the first positiveLyapunov exponent (L1) which is one of indicator of nonlinear dynamic to evaluate the brain function in chemical seizure models METHODS: Lithium-Pilocarpine induced seizure model and kainic acid induced seizure model are used. From serial EEG according to seizure stages. 32.768 sec of data (16.384 data point) were recorded and digirized by a 12-bit analog-digital converter in an IBM PC. The data from serial EEG according to seizure stageswere analyzed for determining the L1. We used the time delays calculated by the method of mutual information to reconstruct the attactor. Time delays of 46-58 msec and enbedding dimensions of 13-19 were used for chemical seizure model. The L1 were calculated for 4 channels. RESULTS: The averaged valued of L1 were serially decreased in both lithium-pilocarpin model and kainic acid model according to increasing seizure stages. CONCLUSION: Our results reveal the decrease of the chaotic activity according to increasing seizure stage. It is suggested that the brain has decreased information procedding and a less flexible neural network during seizure. However further evaluation is required because the significance of these changes are not confirmed.

A preliminary Study for Nonlinear Dynamic Analysis of EEG in Patients with Dementia of Alzheimer

The changes of electroencephalogram(EEG) in patients with dementia of Alzheimer's type are most commonly studied by analyzing power or magnitude in traditionally defined frequency bands. However because of the absence of an identified metric which quantifies the complex amount of information, there are many limitations in using such a linear method. According to the chaos theory, irregular signals of EEG can be also resulted from low dimensional deterministic chaos. Chaotic nonlinear dynamics in the EEG can be studied by calculating the largest Lyapunov exponent(L1). The authors have analyzed EEG epochs from three patients with dementia of Alzheimer's type and three matched control subjects. The largest L1 is calculated from EEG epochs consisting of 16.384 data points per channel in 15 channels. The results showed that patients with dementia of Alzheimer's type had significantly lower L1 than non-demented controls on 8 channels. Topographic analysis showed that the L1 were significantly lower in patients with Alzheimer's disease on all the frontal, temporal, central, and occipital head regions. These results show that brains of patients with dementia of Alzheimer's type have a decreased chaotic quality of electrophysiological behavior. We conclude that the nonlinear analysis such as calculating the L1 can be a promising tool for detecting relative changes in the complexity of brain dynamics.