• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.9
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• pp.897-903
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• 2011

This paper presents a highly linear power amplifier MMIC, having an output power level of about 1 watt, based on InGaP/GaAs hetero-junction bipolar transistor(HBT) technology for the 900 MHz band. The active bias circuit is applied to minimize the effect of temperature variation. Ballast resistors are optimized to prevent a current collapse and a thermal runaway. The fabricated power amplifier exhibited a gain of 17.6 dB, an output P1dB of 30 dBm, and a PAE of 44.9 % at an output P1dB from the one-tone excitation. It also showed a very high OIP3 of 47.3 dBm at an average output power of 20 dBm from the two-tone excitation.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.3687-3693
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• 2012

Objective: The current meta-analysis was performed to address a more accurate estimation of the association between glutathione S-transferase P1 (GSTP1) codon 105 polymorphism and risk of gastric cancer (GC), which has been widely reported with conflicting results. Methods: A comprehensive literature search was conducted to identify all the relevant studies. Fixed or random effect models were selected based on the heterogeneity test. Publication bias was estimated using Begg's funnel plots and Egger's regression test. Results: A total of 20 studies containing 2,821 GC cases and 6,240 controls were finally included in the analyses. Overall, no significant association between GSTP1 polymorphism and GC risk was observed in worldwide populations. However, subgroup analysis stratified by ethnicity showed that GSTP1 polymorphism was significantly associated with increased risk of GC in Asians (G vs. A, OR = 1.273, 95%CI=1.011-1.605; GG vs. AA, OR=2.103, 95%CI=1.197-3.387; GG vs. AA+AG, OR =2.103, 95%CI=1.186-3.414). In contrast, no significant association was found in Caucasians in any genetic models, except for with AG vs. AA (OR=0.791, 95%CI=0.669-0.936). Furthermore, the GSTP1 polymorphism was found to be significantly associated with GC in patients with H. pylori infection and in those with a cardiac GC. Subgroup analysis stratified by Lauren's classification and smoking status showed no significant association with any genetic model. No studies were found to significantly influence the pooled effects in each genetic mode, and no potential publication bias was detected. Conclusion: This meta-analysis suggested that the GSTP1 polymorphism might be associated with increased risk of GC in Asians, while GSTP1 heterozygote genotype seemed to be associated with reduced risk of GC. Since potential confounders could not be ruled out completely, further studies are needed to confirm these results.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5889-5897
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• 2015

Background: The performance of combined testing visual inspection with acetic acid (VIA) and cervical cytology tests might differ from one setting to another. The average estimate of the testing accuracy across studies is informative, but no meta-analysis has been carried out to assess this combined method. Objective: The objective of this study was to estimate the average sensitivity and specificity of the combined VIA and cervical cytology tests for the detection of cervical precancerous lesions. Materials and Methods: We conducted a systematic review and a meta-analysis, according to the Cochrane Handbook for Systematic Review of Diagnostic Test Accuracy. We considered two cases. In the either-positive result case, a positive result implies positivity in at least one of the tests. A negative result implies negativity in both tests. In the both-positive case, a positive result implies having both tests positive. Eligible studies were identified using Pubmed, Embase, Website of Science, CINHAL and COCRANE databases. True positive, false positive, false negative and true negative values were extracted. Estimates of sensitivity and specificity, positive and negative likelihood (LR) and diagnostic odds ratios (DOR) were pooled using a hierarchical random effect model. Hierarchical summary receiver operating characteristics (HSROC) were generated and heterogeneity was verified through covariates potentially influencing the diagnostic odds ratio. Findings: Nine studies fulfilled inclusion criteria and were included in the analysis. Pooled estimates of the sensitivities of the combined tests in either-positive and both-positive cases were 0.87 (95% CI: 0.83-0.90) and 0.38 (95% CI: 0.29-0.48), respectively. Corresponding specificities were 0.79 (95% CI: 0.63-0.89) and 0.98 (95% CI: 0.96-0.99) respectively. The DORs of the combined tests in either-positive or both-positive result cases were 27.7 (95% CI: 12.5-61.5) and 52 (95% CI: 22.1-122.2), respectively. When including only articles without partial verification bias and also a high-grade cervical intraepithelial neoplasia as a threshold of the disease, DOR of combined test in both-positive result cases remained the highest. However, DORs decreased to 12.1 (95% CI: 6.05-24.1) and 13.8 (95% CI: 7.92-23.9) in studies without partial verification bias for the combined tests in the either-positive and both-positive result cases, respectively. The screener, the place of study and the size of the population significantly influenced the DOR of combined tests in the both-positive result case in restriction analyses that considered only articles with CIN2+ as disease threshold. Conclusions: The combined test in the either-positive result case has a high sensitivity, but a low specificity. These results suggest that the combined test should be considered in developing countries as a primary screening test if facilities exist to confirm, through colposcopy and biopsy, a positive result.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5709-5714
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• 2014

Background: An association between alcohol/tobacco use and risk of metastasis in breast cancer has been clearly shown. Materials and Methods: The present study explored, in 48 samples of tissue from mammary ductal carcinoma (taken from Mexican women with an average age of $58.2{\pm}10.9$ years), the association of risk of metastasis with the status of hormonal receptors and the c-erbB2 protein (by immunohistochemistry) as well as clinical, histopathological and sociodemographic factors. Results: Of 48 patients, 41.6% (20/48) presented with metastasis, 43.8% were positive for the estrogen receptor (RE+), 31.3% for the progesterone receptor (RP+) and 47.7% for c-erbB2 (c-erbB2+). The following combinations were found: RE+/RP+/c-erbB2+ 8.3%, RE+/RP+ 22.9%, RE+/RP- 20.8%, RE-/RP+ 8.3%, RE-/RP-/c-erbB2- 22.9% and RE-/RP- 47.8%. There were 12 patients who used alcohol/tobacco, of which 91.6% did not present metastasis and 81.9% were RE-/RP-. Compared to the RE-/RP-/c-erbB2+, the RE+/RP+/c-erbB2+ group had a 15-fold greater risk for metastasis (95%CI, 0.9-228.8, p=0.05). The carriers of the double negative hormonal receptors had a 4.7 fold greater probability of being (or having been) smokers or drinkers (95%CI, 1.0-20.4, p = 0.03). Conclusions: There was a clear protective effect of using alcohol and/or tobacco, in the cases included in the present study of mammary ductal carcinoma, associated with double negative hormonal receptors. However, this association could be due to a protective factor not measured (Neyman bias) or to a bias inherent in the rate of hospitalization (Berkson fallacy). This question should be explored in a broad prospective longitudinal study.

• Journal of Life Science
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• v.20 no.11
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• pp.1738-1741
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• 2010

Caliper measurements of tumor volume have been widely used in the assessment of tumors in animal models. However, experiments based on caliper data have resulted in unreliable estimates of tumor growth, due to necrotic areas of tumor mass. To overcome this systematic bias, we engineered a new luciferase-expressing rat prostate cancer cell line (MLL-Luc) that produces bioluminescence from viable cancer cells. MLL-Luc cells showed a strong correlation between bioluminescence intensity and cell number ($R^2$=0.99) and also accurately quantified tumor growth, with reduced bioluminescence signals caused by necrotic cells in a subcutaneous MLL-Luc xenograft model. The accurate quantification of tumor growth with bioluminescence imaging (BLI) was confirmed by a better antitumor effect of combination chemotherapy, compared to that based on caliper measurements with a correlation between the bioluminescence signal and tumor volume ($R^2$=0.84). These data suggest that bioluminescent MLL xenografts are a powerful and quantitative tool for monitoring tumor growth and are useful in evaluating the efficacy of anticancer drugs, with less systematic bias.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.407-421
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• 2016

This paper reports a meta-analysis of sixteen studies that evaluated the efficacy of cognitive behavioral therapy (CBT) for persistent primary insomnia. PubMed, Cochrane Library, EMBASE, CINAHL and several Korean databases were searched between January 2015 and June 2015. The main search strategy involved the terms that indicate CBT-I (Cognitive Behavioral Therapy-Insomnia) and presence of insomnia. Methodological quality was assessed using Cochrane's Risk of Bias. Data were analyzed by the RevMan 5.3 program of Cochrane Library. Sixteen clinical trials met the inclusion criteria, resulting in a total of 1503 participants. Stimulus control, sleep restriction, sleep hygiene education, and cognitive restructuring were the main treatment components. CBT-I was conducted for a mean of 5.4 weeks, 5.5 sessions, and an average of 90 minutes per session. The effects of CBT-i on total sleep time (d=-0.31), sleep onset latency (d=-0.29), awakening time after sleep onset (d=-0.55), sleep efficiency (d=-0.70), insomnia severity (d=-0.77) and sleep belief (d=-0.64) were significant. Overall, we found a range from small to moderate effect size. CBT-I also was effective for anxiety (d=-0.30) and depression (d=-0.35). The findings demonstrate that CBT-I interventions will lead to the improvement of both sleep quality and quantity in patients with insomnia.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.32 no.4
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• pp.62-89
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• 2019

Objectives : The purpose of this study is to evaluate the effectiveness and safety of topical nasal application of Herbal medicine compared with Western medicine in the treatment of Allergic Rhinitis(AR). Methods : Electronic databases including Cochrane library, PubMed, EMBASE, CNKI, KMBASE, KISS, NDSL, OASIS, KISS and KJTK(Korean Traditional Knowledge Portal) were searched by the keywords such as 'allergic rhinitis', 'nasal sprays', 'herbal medicine', 'plant extracts', and 'external application'. The quality of each RCTs was assessed by Cochrane Collaboration of 'Risk of bias(RoB) Tool'. Results : 19 RCTs were finally selected from 1419 references screened. 19 RCTs were compared with the effects of topical nasal application of Herbal medicine and Western medicine. Based on the symptom scores from 13 RCTs, topical nasal application of herbal medicine generally has a better effect on relief of AR. The two treatments have similar effects on improving the level of specific factors like IgE, IgG, IL-13, $uLTD_4$ in blood and urine. 8 RCTs showed adverse effects(AEs) in both groups and severe AEs were not reported. Conclusions : This study shows that topical nasal application of herbal medicine can improve symptoms and related factors of allergic rhinitis. Well-designed RCT studies with low risk of bias should be conducted to confirm these findings.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.5
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• pp.379-396
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• 2021

Background: Trigeminal neuralgia (TN) is characterized by brief, unilateral, sharp, stabbing, and shooting pain of the fifth cranial nerve. The objective of this systematic review with meta-analysis was to determine the effect of medications compared to placebo in adult patients with TN. Methods: Review authors identified randomized placebo-controlled trials (RCTs) from PubMed, Web of Science, Cochrane, and EMBASE up to February 2021. We assessed the inclusion and exclusion criteria as well as the risk of bias of the studies based on the Cochrane Handbook. A total of 324 unduplicated references were scanned independently and reduced to eight relevant RCTs, with 89 patients included. Medications investigated included oral carbamazepine, subcutaneous sumatriptan, lidocaine (intranasal, 8% spray on the oral mucosa or intravenous), buprenorphine (ganglionic local opioid analgesia), and oral Nav1.7, a selective sodium channel blocker. Results: Meta-analyses showed that overall patients receiving lidocaine reported a significantly lower post-treatment intensity of pain -3.8 points on a 0-10 scale (95% Cl = -4.653 to -2.873; P < 0.001). Patients who received lidocaine were 8.62 times more likely to have pain improvement than patients on placebo (P < 0.001). In one RCT, patients receiving oral carbamazepine showed a significant improvement in pain intensity of -32% compared to the placebo (P < 0.001). In one trial, patients receiving 3 mg subcutaneous sumatriptan had a significantly lower intensity of pain on average -6.1 points on a scale of 0-10 compared to placebo (P < 0.001) and a significant improvement in pain intensity of -75% compared to the improvement in the placebo group (P < 0.001). Patients who received subcutaneous sumatriptan were 10 times more likely to have pain improvement than those who received placebo (P = 0.001) in one study. Due to the unclear/high risk of bias and small sample size, the quality of the evidence for lidocaine in the treatment of TN was low. Conclusion: Further studies are needed for carbamazepine, sumatriptan, buprenorphine, and oral Nav1.7 sodium channel blockers, as only one study reported outcomes.

• The Journal of Korean society of community based occupational therapy
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• v.8 no.3
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• pp.77-89
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• 2018

Objective : The purpose of this study was to analyze occupational therapy intervention on the community mobility for stroke patients, and to provide evidence of intervention in the clinical fields. Methods : A systematic review was executed according to the PRISMA checklist. The accessed database was PubMed, EMBASE, Cochrane Library (CENTRAL), ProQuest Dissertations & thesis (PQDT), RISS, and KoreaMed. We included the articles published from 2005 to September 2018. RoBANS checklist was used to evaluate the quality of the articles. Included articles, totally eight, were categorized according to the type of intervention. Results : The study design of the literature was varied from two-group randomized trial, quasi-experimental study, case-control trial, one group pre-post comparison study, and cross-sectional study. In the evidence level, 6 articles were included in level II (75%). The percentage of low risk of bias in each article ranged from 52.5%~87.5%. Four studies (50%) provided intervention based on virtual reality or virtual environment. The three (37.5%) provided intervention based on the protocol, and the other (12.5%) did wheelchair training. All studies reported significant effects of the intervention. Conclusion : This systematic review provided evidences to use proper intervention in the clinical fields. Various type of studies should be conducted to prove the effect of occupational therapy intervention for community mobility.

• Journal of Nutrition and Health
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• v.54 no.5
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• pp.459-473
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• 2021

Purpose: Although numerous systematic reviews or meta-analysis have reported the hypotensive effects of garlic, the application of these results in the area of functional food is limited. This is because the trials used various garlic preparations and patients with differing hypertensive intensities. To validate the use of garlic powder as a blood pressure lowering functional food, we performed the current meta-analysis, focusing on the study of prehypertensive subjects. Methods: Literature search was carried out using various database up to July 2020, including PubMed, Cochrane, ScienceDirect and Korean studies Information Service System, and each study was screened by pre-stated inclusion/exclusion criteria. We identified nine trials that met the eligibility, of which two studies with moderate or high risk of bias were excluded. Results: Meta-analysis of the seven studies revealed that an intake of garlic powder significantly lowered the systolic blood pressure (SBP) and diastolic blood pressure (DBP) by -6.0 mmHg (95% confidence interval [CI], -11.2, -0.8; p = 0.025) and -2.7 mmHg (95% CI, -5.3, -0.1; p = 0.046), respectively. Shapes of the funnel plot for both SBP and DBP seemed symmetrical, and the Egger's regression revealed no publication bias. Moreover, duration of the intervention period was inversely associated with the pooled effects of garlic powder on SBP (p = 0.019) and DBP (p = 0.019), and this result was supported by the subgroup-analysis. The daily dose of garlic powder, baseline value of each biomarker, and subject number, did not moderate the effects on SBP and DBP. Conclusion: Results of the present meta-analysis indicate that garlic powder supplements are superior to placebo for improving the BP in prehypertensive individuals.