• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2007.06a
• /
• pp.515-516
• /
• 2007

A novel design of contious-time filter for direct conversion receiver applications is proposed. The filter supports different modes including GSM, WCDMA. A 5th chebyshev filter is realized in a gm-C filter topology. The filter circuit is implemented in a standard CMOS $0.35{\mu}m$ processing parameter with a supply voltage of 2.5V. The HSPICE results show that the filter has 200KHz and 5MHz cutoff frequency, and each 3.4us and 85.44us gm value.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.6
• /
• pp.2473-2476
• /
• 2012

Background: In papillary and follicular thyroid cancers (PTC, FTC), nodal and distant metastasis are generally considered important determinants of recurrence and survival, respectively. However, there is no consensus about the threshold primary tumour size (PTS) for these determinants. The aim of this study was to assess size relationships for developing nodal, pulmonary, bone and overall distant metastases. Methods: This prospective study covered 139 (93 females and 46 males) consecutive biopsy proven patients with PTC (114/139, mean age $41.0{\pm}15.7$ years, M: F, 35%:65%) and FTC (25/139, mean age $39.2{\pm}14.3$ years, M: F: 24%:76%). Results: Average primary tumor size was $23.4{\pm}11.1$ mm and $26.5{\pm}13.1$ mm for PTC and FTC respectively (p value=0.223). Nodal metastasis was found more common in PTC than FTC (49% vs 28%, p value <0.05), whereas overall distant metastasis was approximately the same (13% and 24%, p value=0.277); however, bone metastasis was significantly higher in FTC than PTC (24% vs 5%, p value <0.05). Cumulative risk for nodal and distant metastases for FTC and PTC starts at PTS <20 mm and may indicate an unusual aggressive tumor behavior in the studied population. Highest cumulative risk for nodal and pulmonary metastases in PTC and for bone metastasis in FTC was found to be ${\geq}50$ mm PTS. Conclusion: We conclude that a PTS of <20 mm may indicate an unusual aggressive tumor behavior with highest cumulative risk for nodal and pulmonary metastases in PTC and for bone metastasis in FTC with a cutoff of ${\geq}50$ mm.

• Quality Improvement in Health Care
• /
• v.22 no.2
• /
• pp.15-25
• /
• 2016

Objectives: In this study, we examined the validity of Clostridium difficile culture results as a proxy measure of Clostridium difficile infection, and inferred the epidemiologic characteristics of Clostridium difficile infection by tracking the trends of Clostridium difficile culture results. Methods: We reviewed the medical records to figure out the actual possibilities of Clostridium difficile infection of those with positive or negative results of Clostridium difficile culture during the time span from January 2012 to March 2012. We calculated the positive and negative predictive value of Clostridium difficile culture results for Clostridium difficile infection. Furthermore, epidemiologic characteristics of Clostridium difficile infection in a tertiary general hospital in 2012 were analyzed. Result: The estimated positive predictive value of Clostridium difficile culture tests for Clostridium difficile infection was 100%, and the estimated negative predictive value was around 94.4~99.3% depending on the cutoff value of possibility of Clostridium difficile infection. A total of 622 cases were identified as Clostridium difficile infection in a tertiary general hospital in 2012 and there were 4.9 patients with Clostridium difficile infection per 1,000 inpatients. Conclusion: In conclusion, we identified that Clostridium difficile culture results can be used as a proxy measure of Clostridium difficile infection.

• Parasites, Hosts and Diseases
• /
• v.55 no.2
• /
• pp.167-174
• /
• 2017

China still has more than 30,000 patients of advanced schistosomiasis while new cases being reported consistently. D-dimer is a fibrin degradation product. As ascites being the dominating symptom in advanced schistosomiasis, the present study aimed to explore a prediction model of ascites with D-dimer and other clinical easy-achievable indicators. A case-control study nested in a prospective cohort was conducted in schistosomiasis-endemic area of southern China. A total of 291 patients of advanced schistosomiasis were first investigated in 2013 and further followed in 2014. Information on clinical history, physical examination, and abdominal ultrasonography, including the symptom of ascites was repeatedly collected. Result showed 44 patients having ascites. Most of the patients' ascites were confined in the kidney area with median area of $20mm^2$. The level of plasma D-dimer and pertinent liver function indicators were measured at the initial investigation in 2013. Compared with those without ascites, cases with ascites had significantly higher levels of D-dimer ($0.71{\pm}2.44{\mu}g/L$ vs $0.48{\pm}2.12{\mu}g/L$, P=0.005), as well ALB (44.5 vs 46.2, g/L) and Type IV collagen (50.04 vs $44.50{\mu}g/L$). Receiver operating characteristic curve analyses indicated a moderate predictive value of D-dimer by its own area under curve (AUC) of 0.64 (95% CI: 0.54-0.73) and the cutoff value as $0.81{\mu}g/L$. Dichotomized by the cutoff level, D-dimer along with other categorical variables generated a prediction model with AUC of 0.76 (95% CI: 0.68-0.89). Risks of patients with specific characteristics in the prediction model were summarized. Our study suggests that the plasma D-dimer level is a reliable predictor for incident ascites in advanced schistosomiasis japonica patients.

• Tuberculosis and Respiratory Diseases
• /
• v.44 no.4
• /
• pp.785-795
• /
• 1997

Background : Tumor markers have been used in diagnosis, predicting the extent of disease, monitoring recurrence after therapy and prediction of prognosis. But the utility of markers in lung cancer has been limited by low sensitivity and specificity. TPA-M is recently developed marker using combined monoclonal antibody of Cytokeratin 8, 18, and 19. This study was conducted to evaluate the efficacy of new tumor marker, TPA-M by comparing the estabilished markers SCC, CEA, Cyfra21-1 in lung cancer. Method : An immunoradiometric assay of serum CEA, sec, Cyfra21-1, and TPA-M was performed in 49 pathologically confirmed lung cancer patients who visited Keimyung University Hospital from April 1996 to August 1996, and 29 benign lung diseases. Commercially available kits, Ab bead CEA (Eiken) to CEA, SCC RIA BEAD (DAINABOT) to SCC, CA2H (TFB) to Cyfra2H. and TPA-M (DAIICHI) to TPA-M were used for this study. Results : The mean serum values of lung cancer group and control group were $10.05{\pm}38.39{\mu}/L$, $1.59{\pm}0.94{\mu}/L$ in CEA, $3.04{\pm}5.79{\mu}/L$, $1.58{\pm}2.85{\mu}/L$ in SCC, $8.27{\pm}11.96{\mu}/L$, $1.77{\pm}2.72{\mu}/L$ in Cyfra21-1, and $132.02{\pm}209.35\;U/L$, $45.86{\pm}75.86\;U/L$ in TPA-M respectively. Serum values of Cyfra21-1 and TPA-M in lung cancer group were higher than control group (p<0.05). Using cutoff value recommended by the manufactures, that is $2.5{\mu}/L$ in CEA, $3.0{\mu}/L$ in Cyfra21-1, 70.0 U/L in TPA-M, and $2.0{\mu}/L$ in SCC, sensitivity and specificity of lung cancer were 33.3%, 78.6% in CEA, 50.0%, 89.7% in Cyfra21-1, 52.3%, 89.7% in TPA-M, 23.8%, 89.3% in SCC. Sensitivity and specificity of nonsmall cell lung cancer were 36.1%, 78.1% in CEA, 50.1%, 89.7% in Cyfra21-1, 53.1%, 89.7% in TPA-M, 33.8%, 89.3% in SCC. Sensitivity and specificity of small cell lung cancer were 25.0%, 78.5% in CEA, 50.0%, 89.6% in Cyfra21-1, 50.0%, 89.6% in TPA-M, 0%, 89.2% in SCC. Cutoff value according to ROC(Receiver operating characteristics) curve was $1.25{\mu}/L$ in CEA, $1.5{\mu}/L$ in Cyfra2-1, 35 U/L in TPA-M, $0.6{\mu}/L$ in SCC. With this cutoff value, sensitivity, specificity, accuracy and kappa index of Cyfra21-1 and TPA-M were better than CEA and SCC. SCC only was related with statistic significance to TNM stages, dividing to operable stages(TNM stage I to IIIA) and inoperable stages (IIIB and IV) (p<0.05). But no tumor markers showed any correlation with significance with tumor size(p>0.05). Conclusion : Serum TPA-M and Cyfra21-1 shows higher sensitivity and specificity than CEA and SCC in overall lung cancer and nonsmall cell lung cancer those were confirmed pathologically. SCC has higher specificity in nonsmall cell lung cancer. And the level of serum sec are signiticantly related with TNM staging.

• Clinical and Experimental Pediatrics
• /
• v.59 no.3
• /
• pp.126-131
• /
• 2016

Purpose: To evaluate the diagnostic value of the Vesikari Scoring System (VSS) as an early predictor of pathogens in children with acute gastroenteritis (AG). Methods: In this retrospective study, the VSS score, absolute neutrophil count (ANC), and C-reactive protein (CRP) levels were analyzed in 107 hospitalized children with AG, aged 6 months to 17 years. Patients were divided into nonspecific, viral, and bacterial groups according to the pathogens detected using a multiplex polymerase chain reaction (PCR) test. Results: Patients in the bacterial group had significantly higher CRP values and VSS scores compared to those in the viral group and significantly higher VSS scores compared to those in the nonspecific group (P<0.05). Patients in the viral group had significantly higher VSS scores than those in the nonspecific group (P<0.05). Logistic regression analysis revealed that VSS was the most effective diagnostic tool for predicting the type of pathogen (P<0.05). The area under the receiver operating characteristics curve of VSS was significantly greater than that for ANC and CRP (P<0.05). At a cutoff point of 10 in the VSS, an acceptable diagnostic accuracy could be achieved for distinguishing between bacterial and viral pathogens in AG. Conclusion: VSS can be considered a useful and reliable infectious marker for pediatric gastroenteritis. VSS may be a good early predictor of the type of pathogen, enabling development of a treatment plan before results from a stool culture or PCR test are available.

• Clinical and Experimental Pediatrics
• /
• v.56 no.1
• /
• pp.19-25
• /
• 2013

Purpose: Childhood obesity is associated with nonalcoholic fatty liver disease (NAFLD), and it has become one of the most common causes of childhood chronic liver diseases which significant as a cause of liver related mortality and morbidity in children in the United States. The development of simpler and easier clinical indices for medical practice is needed to identify advanced hepatic fibrosis in childhood NAFLD instead of invasive method like liver biopsy. FibroScan and aspartate aminotransferase (AST)-to-platelet ratio index (APRI) have been proposed as a simple and noninvasive predictor to evaluate hepatic fibrosis in several liver diseases. APRI could be a good alternative to detect pathologic change in childhood NAFLD. The purpose of this study is to validate the efficacy of APRI for assessing hepatic fibrosis in childhood NAFLD based on FibroScan. Methods: This study included 23 children with NAFLD who underwent FibroScan. Clinical, laboratory and radiological evaluation including APRI was performed. To confirm the result of this study, 6 patients received liver biopsy. Results: Factors associated with hepatic fibrosis (stiffness measurement >5.9 kPa Fibroscan) were triglyceride, AST, alanine aminotransferase, platelet count, APRI and collagen IV. In multivariate analysis, APRI were correlated with hepatic fibrosis (>5.9 kPa). In receiver operating characteristics curve, APRI of meaningful fibrosis (cutoff value, 0.4669; area under the receiver operating characteristics, 0.875) presented sensitivity of 94%, specificity of 66%, positive predictive value of 94%, and negative predictive value of 64%. Conclusion: APRI might be a noninvasive, simple, and readily available method for medical practice to predict hepatic fibrosis of childhood NAFLD.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.2
• /
• pp.497-501
• /
• 2016

Aim: To evaluate the relationship between pre-operative CA-125 levels and myometrial invasion in patients with early-stage endometrioid-type endometrial cancer. Materials and Methods: Two-hundred and sixty patients were diagnosed with endometrial cancer between January 2007 and December 2012. Of these, 136 patients with stage 1 endometrioid histologic-type and documented pre-operative serum CA-125 levels were included in the study. Age, preoperative CA-125 level, histologic grade, surgical grade, and presence of deep myometrial invasion were recorded. Additionally, 16, 20, and 35 IU/ml cutoff values were used and compared to evaluate the relationship between pre-operative CA-125 levels and myometrial invasion. Results: The average serum CA-125 level was $35.4{\pm}36.7$ in patients with deep myometrial invasion, and $21.5{\pm}35.8$ in cases without deep myometrial invasion. The relationship between the presence of deep myometrial invasion and CA-125 cut-off values (16, 20, 35 IU/ml) was statistically significant, although the correlation was weak (p<0.05). When the relationship between 16, 20 and 35 IU/ml CA-125 cut-off values and the presence of deep myometrial invasion was studied, specifity and sensitivity values were identified as: 0.60-0.68 for 16 IU/ml; 0.73-0.48 for 20 IU/ml; and 0.89-0.33 for 35 IU/ml. The sensitivity of 16 IU/ml cut-off value was higher when compared to other values. Conclusions: This study demonstrates that preoperative serum CA-125 values maybe used as a predictive test in patients with early stage endometrioid-type endometrium cancer, and as a prognostic factor alone. Further studies should be conducted to identify different CA-125 cut-off values in patients with low risk endometrial cancer.

• Radiation Oncology Journal
• /
• v.35 no.2
• /
• pp.163-171
• /
• 2017

Purpose: Although stereotactic ablative body radiotherapy (SABR) is widely used therapeutic technique, predictive factors of radiation pneumonitis (RP) after SABR remain undefined. We aimed to investigate the predictive factors affecting RP in patients with primary or metastatic lung tumors who received SABR. Materials and Methods: From 2012 to 2015, we reviewed 59 patients with 72 primary or metastatic lung tumors treated with SABR, and performed analyses of clinical and dosimetric variables related to symptomatic RP. SABR was delivered as 45-60 Gy in 3-4 fractions, which were over 100 Gy in BED when the ${\alpha}/{\beta}$ value was assumed to be 10. Tumor volume and other various dose volume factors were analyzed using median value as a cutoff value. RP was graded per the Common Terminology Criteria for Adverse Events v4.03. Results: At the median follow-up period of 11 months, symptomatic RP was observed in 13 lesions (12 patients, 18.1%), including grade 2 RP in 11 lesions and grade 3 in 2 lesions. Patients with planning target volume (PTV) of ${\leq}14.35mL$ had significantly lower rates of symptomatic RP when compared to others (8.6% vs. 27%; p = 0.048). Rates of symptomatic RP in patients with internal gross tumor volume (iGTV) >4.21 mL were higher than with ${\leq}4.21mL$ (29.7% vs. 6.1%; p = 0.017). Conclusions: The incidence of symptomatic RP following treatment with SABR was acceptable with grade 2 RP being observed in most patients. iGTV over 4.21 mL and PTV of over 14.35 mL were significant predictive factors related to symptomatic RP.

• Clinical and Experimental Pediatrics
• /
• v.63 no.8
• /
• pp.329-334
• /
• 2020

Background: Birth asphyxia is a leading cause of neonatal mortality. Ischemia-modified albumin (IMA) levels may have a predictive role in the identification and prevention of hypoxic disorders, as they increase in cases of ischemia of the liver, heart, brain, bowel, and kidney. Purpose: This study aimed to assess the value of IMA levels as a diagnostic marker for neonatal hypoxic-ischemic encephalopathy (HIE). Methods: Sixty newborns who fulfilled 3 or more of the clinical and biochemical criteria and developed HIE as defined by Levene staging were included in our study as the asphyxia group. Neonates with congenital malformation, systemic infection, intrauterine growth retardation, low-birth weight, cardiac or hemolytic disease, family history of neurological diseases, congenital or perinatal infections, preeclampsia, diabetes, and renal diseases were excluded from the study. Sixty healthy neonates matched for gestational age and with no maternal history of illness, established respiration at birth, and an Apgar score ≥7 at 1 and 5 minutes were included as the control group. IMA was determined by double-antibody enzyme-linked immunosorbent assay of a cord blood sample collected within 30 minutes after birth. Results: Cord blood IMA levels were higher in asphyxiated newborns than in controls (250.83±36.07 pmol/mL vs. 120.24±38.9 pmol/mL). Comparison of IMA levels by HIE stage revealed a highly significant difference among them (207.3±26.65, 259.28±11.68, 294.99±4.41 pmol/mL for mild, moderate, and severe, respectively). At a cutoff of 197.6 pmol/mL, the sensitivity was 84.5%, specificity was 86%, positive predictive value was 82.8%, negative predictive value was 88.3%, and area under the curve was 0.963 (P<0.001). Conclusion: IMA levels can be a reliable marker for the early diagnosis of neonatal HIE and can be a predictor of injury severity.