• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.5
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• pp.43-51
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• 2010

Attenuation coefficients of medical ultrasound not only reflect the pathological information of tissues scanned but also provide the quantitative information to compensate the decay of backscattered signals for other medical ultrasound parameters. Based on the frequency-selective attenuation property of human tissues, attenuation estimation methods in spectral domain have difficulties for real-time implementation due to the complexicity while estimation methods in time domain do not achieve the compensation for the diffraction effect effectively. In this paper, we propose the modified VSA method, which compensates the diffraction with reference phantom in time domain, using adaptive bandpass filters with decreasing center frequencies along depths. The adaptive bandpass filtering technique minimizes the distortion of relative echogenicity of wideband transmit pulses and maximizes the signal-to-noise ratio due to the random scattering, especially at deeper depths. Since the filtering center frequencies change according to the accumulated attenuation, the proposed algorithm improves estimation accuracy and precision comparing to the fixed filtering method. Computer simulation and experimental results using tissue-mimicking phantoms demonstrate that the distortion of relative echogenicity is decreased at deeper depths, and the accuracy of attenuation estimation is improved by 5.1% and the standard deviation is decreased by 46.9% for the entire scan depth.

• Journal of Gastric Cancer
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• v.6 no.2
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• pp.84-90
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• 2006

Purpose: The macroscopic findings of tumors are not always identical with the microscopic findings. This study investigated the oncologic implications of macroscopic serosal invasion in advanced gastric cancer to find out how to improve the accuracy for the depth of invasion assessed by the surgeon during an operation. Materials and Methods: The medical records of 789 patients with advanced gastric cancer who underwent a gastrectomy at Kyungpook National University Hospital between 1995 and 1999 were reviewed. The prognoses and the recurrence patterns were analyzed according to macroscopic serosal invasion and microscopic serosal invasion, and the clinico-pathological factors of cT3/ss cancers were compared with those of cT3/se cancers. Results: Difference of survival rates according to macroscopic serosal invasion and microscopic serosal invasion revealed statistically significant. Recurrence rates were similar in patients with macroscopic and microscopic serosal invasion (42.2% and 41.4%, respectively). Peritoneal recurrence rates were also similar (19.8% and 21.9%, respectively). The sensitivity and the specificity of macroscopic assessment of serosal invasion were 70.3% and 77.8%, respectively, On univariate and multivariate analyses, Borrmann type I/II cancers and the absence of distant metastases revealed the risk factors for overestimating of serosal invasion. Conclusion: Macroscopic serosal invasion assessed by a surgeon intraoperatively can be used to give a prognosis and to predict the recurrence pattern precisely, although there is a risk for overestimation when the tumor is a Borrmann type I/II cancer or the tumor has no distant metastases. (J Korean Gastric Cancer Assoc 2006;6:84-90)

• Investigative Magnetic Resonance Imaging
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• v.20 no.3
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• pp.158-166
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• 2016

Purpose: To understand clinical significance of irregular interface between meningioma and adjacent brain parenchyma in predicting histological grading of tumor, focusing on brain parenchymal invasion. Materials and Methods: Pathologically confirmed 79 cases with meningiomas with pathological reports about the presence of parenchymal invasion were included. We defined the presence of interface irregularity as either spiculations or fuzzy margins between the tumor and brain parenchyma. We counted number of spiculations and measured ratio of fuzzy margin length to whole length of mass with consensus of two neuroradiologists. We classified the patients into Present group and Absent group, and the two groups were compared by using the Mann-Whitney U test. Statistical correlations between the presence of an interface irregularity and brain parenchymal invasion by the tumor as well as meningioma histological grade were tested with chi-square test. The optimal cutoff values of spiculation numbers and the ratio of fuzzy margins were determined. The sensitivity and specificity of number of spiculations, ratio of fuzzy margin and the presence of irregular interface as combined parameters for predicting the parenchymal invasion were calculated using ROC curve analysis. Results: Statistically significant differences were noted between the Present and Absent groups for number of spiculations and ratio of fuzzy margin (P = 0.038 and P = 0.028, respectively). The optimal cutoff value for number of spiculations (> 4.5 with 61.1% sensitivity and 68.9% specificity) and the ratio of fuzzy margin (> 0.24 with 66.7% sensitivity and 65.6% specificity) were determined. The sensitivity and specificity of interface irregularity as the combined parameters were 72% and 59%, respectively. The interface irregularity between tumor and brain parenchyma significantly correlated with not only brain parenchymal invasion (P = 0.001) and but also histological grade (P < 0.001). Conclusion: The interface irregularity between tumor and brain parenchyma in MRI can be a strong predictive factor for brain parenchymal invasion and high grade meningioma.

• The Journal of Korean Medicine
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• v.27 no.3 s.67
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• pp.51-62
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• 2006

Objective: Although chronic non-bacterial prostatitis is a common disease, it is very difficult to treat effectively. Lygodium japonicum has traditionally been used in treatment of urinary tract inflammation and voiding disturbance. In this study, we investigated the therapeutic effects and action mechanism of Lygodium japonicum in the rat model of non-bacterial prostatitis induced by castration and testosterone treatment. Methods: Five-month-old rats were treated with $17\beta-estradiol$ after castration for induction of experimental non-bacterial prostatitis, which is similar to human chronic prostatitis in histopathological profiles. Lygodium japonicum and testosterone were administered as an experimental specimen and a positive control, respectively. The prostates were evaluated by histopathological parameters including the epithelial score and epithelio-stromal ratio for glandular damage, proliferating cell nuclear antigen (PCNA) labeling index for cyto-proliferation and a TUNEL (deoxyuridine triphosphate biotin nick end-labeling) assay for cell apoptosis. Results: While prostates of control rats revealed severe acinar gland atrophy and stromal proliferation, the rats treated with Lygodium japonicum showed a lesser range of tissue damage. Epithelial score was improved in Lygodium japonicum than that of the control (P<0.05). The epithelio-stromal ratio was lower in Lygodium japonicum when compared to that of the control (P<0.05). Although there was no difference in PCNA and TUNEL positive cells of the glandular epithelia, we found an decreased number of PCNA positive cell and concurrent increase of TUNEL positive cells in the stroma of Lygodium japonicum treated rats (P<0.01). Conclusions: These findings suggest that Lygodium japonicum may protect the glandular epithelial cells and also inhibit stromal proliferation in association with suppression of cyto-proliferation and stimulation of apoptosis. We concluded that Lygodium japonicum may be a useful remedy agent for treating the chronic non-bacterial prostatitis.

• Korean Journal of Biological Psychiatry
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• v.5 no.1
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• pp.83-94
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• 1998

Objectives : Phencyclidine(PCP) or PCP-like substances such as ketamine have been known to rekindle the cognitive dysfunction in schizophrenia. The aims of this study were to identify whether PCP-like substances can produce cognitive deficit in schizophrenia, to discuss relation with aging process, and finally to speculate underlying neurochemical mecha-nisms by various drug responses. Methods : In experiment I, radial maze tests were done in 24 Sprague-Dawley rats for 3 days to get baseline data. Being divided into 4 groups(6 rats respectively) of normal aged, normal adult controls, atropine-treated and ketamine-treated, the radial maze tests were repeated on every week for 6 weeks, and then the rats were sacrificed by intracardiac perfusion with phosphate-buffered 10% formaldehyde solution for histology. The brain specimen was stained with hematoxylin-eosin to count cells in the prefrontal cortex and hippocampus. In experiment II, radial maze tests were done for 48 rats before any drug treatment and only after ketamine administration. Thereafter, haloperidol, bromocriptine, clonidine, nimodipine, tacrine, valproic acid, naloxone and fluoxetine were intramuscularly injected on every other day in addition to ketamine. Radial maze tests were repeated on every week for 6 weeks, and then rats were prepared by the same procedure for histology. Results : 1) Reaction times of radial maze tests of atropine-treated rats were significantly prolonged than those of normal aged(p<0.05) or normal adult controls(p<0.05). Cell numbers of prefrontal cortex & hippocampus in ketamine-treated rats were significantly reduced than those in normal aged (p<0.05) or normal adult controls(p<0.005). 2) Reduced cell numbers by ketamine became significantly raised by tacrine administration in prefrontal cortex & hippocampus(p<0.05), while there were no significant changes on radial maze tests. Cell numbers also tended to be raised by nimodipine, fluoxetine and haloperidol administration. Conclusions : In conclusion, the visuospatial memory disorders in ketamine-induced psychotic rats might be partly asso-ciated with aging process. Furthermore, the responses to the various drugs suggested cholinergic system might have an important role in the neurochemical mechanism of the cognitive dysfunction in ketamine-induced psychosis. Otherwise, calcium metabolism as well as serotonergic and dopaminergic systems seemed to be possibly related.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.5
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• pp.1106-1115
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• 2009

Mori Ramulus has multiple applications in Korean traditional medicine prescription because it has antioxidant and anti-inflammatory effects by reducing macrophage activities. Yet, no studies on the anti-arthritic activity of EMR (extract of Mori Ramulus) have been reported in vitro and in vivo. Rheumatoid arthritis (RA) is a systemic autoimmune disease with chronic inflammation characterized by hyperplasia of synovial cells in affected joints, which ultimately leads to the destruction of cartilage and bone. Because collagen-induced arthritis (CIA) is similar to RA in pathological symptoms and immune reactions, there have been several reports concerning RA using CIA mouse model. Here, we investigated the effects of Mori Ramulus on RA using CIA mice. The importance of CD4+ Th1 cells in RA progress was previously indicated and studies further showed that Th17 cells play a prime role in severity of disease. Accordingly, the present study was focused on CIA associated with CD4+ Th1 cells and Th1 7 cells. DBA/1OlaHsd mice were immunized with bovine type II collagen (CII). After a second collagen immunization, mice were treated with EMR once a day for 4 weeks. The severity of arthritis within the paw joints was evaluated by histological assessment of cartilage destruction and pannus formation. Immune cells in peripheral blood mononuclear cells (PBMC), draining lymph node (DLN) and paw joints, cytokine production and gene expression were assessed from CIA mouse using ELISA, FACS and real-time PCR analysis. Administration of EMR significantly suppressed the progression of CIA and inhibited the production of TNF-$\alpha$, IL-6 and IL-17 in the serum. The erosion of cartilage was dramatically reduced in mouse knees after treatment with EMR. In conclusion, our results demonstrate that EMR significantly suppressed the progression of CIA and that this action was mediated by the decreased production of TNF-$\alpha$, IL-6, IL-17 and collagen II-specific antibody in the serum. EMR suppressed Th17 cells and reduced level of IL-6 via B cell suppression, and thus, the levels of autoantibodies produced from B cells were decreased. Furthermore, EMR suppressed NKT cells which directly stimulate B cells and develop imbalance of Th1/Th2 cell. Oral administration of EMR (100 mg/kg or 200 mg/kg) significantly suppressed the progression of CIA, which is comparable to that of methotrexate (MTX, 0.3 mg/kg) used as a positive control. We are currently studying the mechanism underlying the therapeutic role for EMR in CIA mice.

• Toxicological Research
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• v.21 no.4
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• pp.339-345
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• 2005

Aflatoxins are produced by Aspergillus flavus, parasiticus that grows in improperly stored cereals. Aflatoxin $B_1\;(AFB_1)$ is a potent hepatocarcinogen in a variety of experimental animals including human beings. In spite of a high attention to the hepatocarcinogenecity of aflatoxins, the relative toxicity of other types $(AFB_2,\;AFG_1\;and\;AFG_2)$ of the toxins is not fully clarified. Sprague-Dawley male rats were orally administered with $AFB_1,\;AFB_2,\;AFG_1\;and\;AFG_2$ at the dose of 250, 1250, and $2500\;{\mu}g/kg$ body weight. Animals were then killed at 12, 24 or 48 hrs following aflatoxin adminstration. Subsequently the relative weight of liver was measured and histopathological examination on the liver was performed. Level of 8-OxodG and expression of ras gene in the liver was determined. The relative liver weights at high doses of $AFB_1\;and\;AFG_1$ was significantly low. The treatment of $AFB_1$ at the high dose of $2500\;{\mu}g/kg$ showed vacuolar degeneration and centrilobular hepatic necrosis with inflammatory cells. The pathological changes by $AFB_2\;AFG_1,\;and\;AFG_2$ were not clearly found. The formation of 8-OxodG by $AFB_1$ increased in a dose-dependent manner up to 24 hrs after a single treatment of $AFB_1$ thereafter decreased to the level of the control. The treatments of $AFB_2\;AFG_1,\;and\;AFG_2$ showed an inconsistent pattern in the formation of 8-OxodG in the liver of rats with increasing time. The expression of ras oncogene in the liver by $AFB_1$ at the dose of $1250\;{\mu}g/kg$ was increased twice compared to the control. The treatments of $AFB_2\;AFG_1,\;and\;AFG_2$ at all doses decreased the expression of ras in the liver. These results in the present study indicate that $AFB_1$ among aflatoxins with low comparable levels is the most toxic as determined by early biomarkers such as 8-OxodG formation and ras expression. However, the levels of 8-OxodG and ras as biomarkers were not useful to predict the relative hepatocarcinogenicity of aflatoxins to $AFB_1$ in the present model. Further studies are required to look for other biomarkers to predict carcinogenic potency of aflatoxins.

• Parasites, Hosts and Diseases
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• v.32 no.4
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• pp.215-222
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• 1994

The relationship between the intestinal histopathology and number and position of' intraepithelial Iymphocytes(IEL) was observed chronologically in the small intestine of rats experimentally infected wiH Metagonimw vokogawci. Fifteen Sprague-Dawley rats were orally infected each with 3,000 metacercariae, and 3 were kept uninfected for controls. Three rats each were sacrificed on the day 5, 10, 15, 24 and 70 post-infection (PI) and samples of the small intestine, 5 cm, 10 cm, 20 cia and 70 cm posterior to the pylonls were taken. The samples were processed routinely and stained with Giemsa. The intestinal histopathology was severe during the day 5-15 PI and characterized by villous atrophy, crypt hyperplasia, and decrease of villus/ciypt height ratio. After the day 24 PI, the intestinal lesions showed some tendency of recovery The number of IEL increased at the early stage of infection, but decreased thereafter to a lower level than that of controls, with progression of the pathological changes. Then, the IEL number began to increase again after the day 24 PI. In control rats, the great majority of the IEL were located at the basal region of the epithelium. During the early stage of infection, however, a considerable proportion of IEL was found to have moved to the intermediate or apical region of the epithelium. From the above results, it is suggested that the change of IEL number and position during the course of M. yokogowoi infection should be closely related to the progression and recovery of the intestinal histopathology.

• Journal of Life Science
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• v.30 no.8
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• pp.722-730
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• 2020

As one of the most serious health risk factors, air pollution can no longer be ignored. Particulate matter (PM) is an important and harmful component of air pollution that originates from a variety of sources. Numerous recent studies have linked PM to a range of conditions including cancer, cardiovascular, respiratory, and skin disease. The eye, despite being directly exposed to air pollution, has been investigated in very few of these studies. In this review, we describe the evidence from in vitro and in vivo studies, as well as epidemiological investigations, that supports the association between exposure to PM and the development of ocular conditions such as surface and retinal disease and glaucoma. Based on the results of previous studies, we suggest that PM exposure can lead to oxidative stress, inflammation, autophagy, and, ultimately, ocular surface disease. Nevertheless, almost no studies focus on ocular surface damage from PM while some epidemiological and clinical studies report on the posterior of the eye. However, the underlying pathological mechanisms in the posterior following PM exposure have yet to be identified, and further studies are therefore warranted of the ocular surface as well as the posterior part of the eye.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6359-6364
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• 2015

Background: Preclinical studies have shown that the combination of an aromatase inhibitor (AI) and capecitabine in estrogen receptor (ER)- positive cell lines enhance antitumor efficacy. This retrospective analysis of a group of patients with metastatic breast cancer (MBC) evaluated the efficacy and safety of combined AI with capecitabine. Materials and Methods: Patients with hormone receptor-positive metastatic breast cancer treated between 1st January 2005 and 31st December 2010 with a combination of capecitabine and AI were evaluated and outcomes were compared with those of women treated with capecitabine in conventional dose or AI as a monotherapy. Results: Of 72 patients evaluated, 31 received the combination treatment, 22 AI and 19 capecitabine. The combination was used in 20 patients as first-line and 11 as second-line treatment. Mean age was 46.2 years with a range of 28-72 years. At the time of progression, 97% had a performance status of <2 and 55% had visceral disease. No significant difference was observed between the three groups according to clinical and pathological features. Mean follow up was 38 months with a range of 16-66 months. The median PFS of first-line treatment was significantly better for the combination (PFS 21 months vs 8.0 months for capecitabine and 15.0 months for AI). For second-line treatment, the PFS was longer in the combination compared with capecitabine and Al groups (18 months vs. 5.0 months vs. 11.0 months, respectively). Median 2 year and 5 year survival did not show any significant differences among combination and monotherapy groups. The most common adverse events for the combination group were grade 1 and 2 hand-for syndrome (69%), grade 1 fatigue (64%) and grade 1 diarrhoea (29%). Three grade 3 hand-foot syndrome events were reported. Conclusions: Combination treatment with capecitabine and AI used as a first line or second line treatment was safe with much lowered toxicity. Prospective randomized clinical trials should evaluate the use of combination therapy in advanced breast cancer to confirm these findings.