BACKGROUND/AIMS: Pancreatic cancer (PC) patients have poor prognoses because this cancer is typically diagnosed at an advanced stage and the therapeutic options are limited. We examined the potential of metabolic profiling for early diagnosis and identification of potential therapeutic targets. METHODS: Ten patients and 10 healthy volunteer controls older than 20 years of age were enrolled between May and December 2015. The patients were confirmed to have pancreatic ductal adenocarcinoma cytologically or histologically. Blood plasma samples were derivatized and analyzed by gas chromatography mass spectrometry (GC-MS). Untargeted GC-MS data were analyzed using statistical methods, including Wilcoxon rank-sum test and principal component analyses. RESULTS: L-lysine was 1.36-fold higher in patients than in healthy controls (p<0.05). L-leucine was 0.63-fold lower (p<0.01) and palmitic acid was 0.93-fold lower (p<0.5) in patients than in controls. Orthogonal partial least squared-discriminant analysis revealed significant differences between the patients and controls. CONCLUSIONS: This study suggests that the metabolic profiles of patients with PC are distinct from those of the healthy population. Further studies are required to develop methods for early diagnosis and identify therapeutic targets.
Adenocarcinoma ; Early Diagnosis ; Gas Chromatography-Mass Spectrometry ; Healthy Volunteers ; Humans ; Korea ; Leucine ; Lysine ; Metabolome ; Palmitic Acid ; Pancreatic Ducts ; Pancreatic Neoplasms ; Plasma ; Principal Component Analysis ; Prognosis

Indobufen (Ibustrin®), a reversible inhibitor of platelet aggregation, exists in two enantiomeric forms in 1:1 ratio. Here, we characterized the anti-platelet effect of S- and R-indobufen using response surface modeling using NONMEM® and predicted the therapeutic doses exerting the maximal efficacy of each enantioselective S- and R-indobufen formulation. S- and R-indobufen were added individually or together to 24 plasma samples from drug-naïve healthy subjects, generating 892 samples containing randomly selected concentrations of the drugs of 0–128 mg/L. Collagen-induced platelet aggregation in platelet-rich plasma was determined using a Chrono-log Lumi-Aggregometer. Inhibitory sigmoid I(max) model adequately described the anti-platelet effect. The S-form was more potent, whereas the R-form showed less inter-individual variation. No significant interaction was observed between the two enantiomers. The anti-platelet effect of multiple treatments with 200 mg indobufen twice daily doses was predicted in the simulation study, and the effect of S- or R-indobufen alone at various doses was predicted to define optimal dosing regimen for each enantiomer. Simulation study predicted that 200 mg twice daily administration of S-indobufen alone will produce more treatment effect than S-and R-mixture formulation. S-indobufen produced treatment effect at lower concentration than R-indobufen. However, inter-individual variation of the pharmacodynamic response was smaller in R-indobufen. The present study suggests the optimal doses of R-and S-enantioselective indobufen formulations in terms of treatment efficacy for patients with thromboembolic problems. The proposed methodology in this study can be applied to the develop novel enantio-selective drugs more efficiently.
Blood Platelets ; Colon, Sigmoid ; Healthy Volunteers ; Humans ; In Vitro Techniques ; Plasma ; Platelet Aggregation ; Platelet-Rich Plasma ; Treatment Outcome

This article was published with a misspelled the date of acceptance. The date of acceptance should be corrected as “March 7, 2013”.
Breast Neoplasms* ; Breast* ; Humans ; Recurrence*

The purpose of this simulation study is to explore the limitation of the population PK/PD analysis using data from a clinical study and to help to construct an appropriate PK/PD design that enable precise and unbiased estimation of both fixed and random PD parameters in PK/PD analysis under different doses and Hill coefficients. Seven escalating doses of virtual drugs with equal potency and efficacy but with five different Hill coefficients were used in simulations of single and multiple dose scenarios with dense sampling design. A total of 70 scenarios with 100 subjects were simulated and estimated 100 times applying 1-compartment PK model and sigmoid E(max) model. The bias and precision of the parameter estimates in each scenario were assessed using relative bias and relative root mean square error. For the single dose scenarios, most PD parameters of sigmoid E(max) model were accurately and precisely estimated when the C(max) was more than 85% of EC₅₀, except for typical value and inter-individual variability of EC₅₀ which were poorly estimated at low Hill coefficients. For the multiple dose studies, the parameter estimation performance was not good. This simulation study demonstrated the effect of the relative range of sampled concentrations to EC₅₀ and sigmoidicity on the parameter estimation performance using dense sampling design.
Bias (Epidemiology) ; Clinical Study ; Colon, Sigmoid*

Simvastatin is a lipid-lowering drug that is metabolized to its active metabolite simvastatin acid (SA). We developed and validated a sensitive liquid chromatography-tandem mass spectrometry (LC/MS/MS) method to quantitate SA in human plasma using a liquid-liquid extraction method with methanol. The protonated analytes generated in negative ion mode were monitored by multiple reaction monitoring. Using 500-mL plasma aliquots, SA was quantified in the range of 0.1-100 ng/mL. Calibration was performed by internal standardization with lovastatin acid, and regression curves were generated using a weighting factor of 1/χ2. The linearity, precision, and accuracy of this assay for each compound were validated using quality control samples consisting of mixtures of SA (0.1, 0.5, 5, and 50 ng/mL) and plasma. The intra-batch accuracy was 95.3-107.8%, precision was -2.2% to -3.7%, and linearity (r2) was over 0.998 in the standard calibration range. The chromatographic running time was 3.0 min. This method sensitively and reliably measured SA concentrations in human plasma and was successfully used in clinical pharmacokinetic studies of simvastatin in healthy Korean adult male volunteers.
Adult ; Calibration ; Humans* ; Liquid-Liquid Extraction ; Lovastatin ; Male ; Mass Spectrometry* ; Methanol ; Plasma* ; Protons ; Quality Control ; Running ; Simvastatin* ; Volunteers

OBJECTIVETo investigate the effects of Korean red ginseng (KRG) on semen parameters in male infertility patients in a randomized, double-blind, placebo-controlled study.

METHODSA total of 80 male infertility patients with varicocele were recruited from April 2011 to February 2012. The subjects were then divided into the following four groups: non-varicocelectomy (V)+placebo (P) group, V+P group, non-V+KRG group (1.5-g KRG daily), and V+KGR group (1.5-g KRG daily). Semen analysis was performed and hormonal levels were measured in each treatment arm after 12 weeks.

RESULTSAll groups but not the non-V+P group, showed significant improvements in sperm concentrations, motility, morphology, and viability at the end of the study. However, there were no significant differences in serum follicle-stimulating hormone, luteinizing hormone, and testosterone among groups. The incidence of adverse events was low, and all events were assumed to be unrelated to the treatments administered.

CONCLUSIONSAlthough the exact mechanism by which KRG improves spermatogenesis remains unclear, KRG may be a useful agent for the treatment of male infertility. Nevertheless, additional studies to evaluate the optimal dose and duration of treatment are needed.

Adult ; Double-Blind Method ; Hormones ; metabolism ; Humans ; Infertility, Male ; drug therapy ; Male ; Panax ; chemistry ; Placebos ; Plant Extracts ; adverse effects ; pharmacology ; therapeutic use ; Semen ; drug effects ; metabolism

The objective of this study was to externally validate a new dosing scheme for busulfan. Thirty-seven adult patients who received busulfan as conditioning therapy for hematopoietic stem cell transplantation (HCT) participated in this prospective study. Patients were randomized to receive intravenous busulfan, either as the conventional dosage (3.2 mg/kg daily) or according to the new dosing scheme based on their actual body weight (ABW) (23×ABW(0.5) mg daily) targeting an area under the concentration-time curve (AUC) of 5924 µM·min. Pharmacokinetic profiles were collected using a limited sampling strategy by randomly selecting 2 time points at 3.5, 5, 6, 7 or 22 hours after starting busulfan administration. Using an established population pharmacokinetic model with NONMEM software, busulfan concentrations at the available blood sampling times were predicted from dosage history and demographic data. The predicted and measured concentrations were compared by a visual predictive check (VPC). Maximum a posteriori Bayesian estimators were estimated to calculate the predicted AUC (AUC(PRED)). The accuracy and precision of the AUC(PRED) values were assessed by calculating the mean prediction error (MPE) and root mean squared prediction error (RMSE), and compared with the target AUC of 5924 µM·min. VPC showed that most data fell within the 95% prediction interval. MPE and RMSE of AUCPRED were -5.8% and 20.6%, respectively, in the conventional dosing group and −2.1% and 14.0%, respectively, in the new dosing scheme group. These fi ndings demonstrated the validity of a new dosing scheme for daily intravenous busulfan used as conditioning therapy for HCT.
Adult* ; Area Under Curve ; Behavior Therapy ; Body Weight ; Busulfan* ; Drug Dosage Calculations ; Hematopoietic Stem Cell Transplantation* ; Hematopoietic Stem Cells* ; Humans ; Pharmacokinetics ; Prospective Studies*

BACKGROUND: Amlodipine is a third-generation dihydropyridine calcium channel blocker, which has proven to be a useful drug against hypertension or angina. METHODS: This randomized, open-label, two-period, two-treatment, single-dose, crossover study was conducted in twenty healthy male volunteers. Subjects were administered 5 mg of the test or reference formulation. After 2-week washout period, the other formulation was administered. Blood samples were collected up to 144 hours after drug administration, and plasma amlodipine concentrations were determined by validated liquid chromatography-tandem mass spectrometry. Drug safety was assessed using measurement of vital signs, physical examinations, laboratory test, electrocardiograms, and adverse event monitoring. RESULTS: All subjects were completed this study. The geometric mean ratios of Cmax and AUClast were 1.078 (90 % CI, 0.968 - 1.200) and 1.095 (90 % CI, 1.011 - 1.186), respectively. There were no serious adverse events were reported by both formulations. CONCLUSION: This study showed the test and reference formulations had similar pharmacokinetics and safety profiles.
Amlodipine ; Calcium Channels ; Cross-Over Studies ; Electrocardiography ; Healthy Volunteers ; Humans ; Hypertension ; Male* ; Mass Spectrometry ; Pharmacokinetics ; Physical Examination ; Plasma ; Vital Signs

PURPOSE: IBTR! 2.0 is a web-based nomogram that predicts the 10-year ipsilateral breast tumor recurrence (IBTR) rate after breast-conserving therapy. We validated this nomogram in Korean patients. METHODS: The nomogram was tested for 520 Korean patients, who underwent breast-conserving surgery followed by radiation therapy. Predicted and observed 10-year outcomes were compared for the entire cohort and for each group, predefined by nomogram-predicted risks: group 1, <3%; group 2, 3% to 5%; group 3, 5% to 10%; group 4, >10%. RESULTS: In overall patients, the overall 10 year predicted and observed estimates of IBTR were 5.22% and 5.70% (p=0.68). In group 1, (n=124), the predicted and observed estimates were 2.25% and 1.80% (p=0.73), in group 2 (n=177), 3.95% and 3.90% (p=0.97), in group 3 (n=181), 7.14% and 8.80% (p=0.42), and in group 4 (n=38), 11.66% and 14.90% (p=0.73), respectively. CONCLUSION: In a previous validation of this nomogram based on American patients, nomogram-predicted IBTR rates were overestimated in the high-risk subgroup. However, our results based on Korean patients showed that the observed IBTR was higher than the predicted estimates in groups 3 and 4. This difference may arise from ethnic differences, as well as from the methods used to detect IBTR and the healthcare environment. IBTR! 2.0 may be considered as an acceptable nomogram in Korean patients with low- to moderate-risk of in-breast recurrence. Before widespread use of this nomogram, the IBTR! 2.0 needs a larger validation study and continuous modification.
Breast ; Breast Neoplasms ; Cohort Studies ; Delivery of Health Care ; Humans ; Mastectomy, Segmental ; Nomograms ; Recurrence

PURPOSE: To present the author's experience with various treatment methods of granulomatous lobular mastitis (GLM) and to determine effective treatment methods of GLM. METHODS: Fifty patients who were diagnosed with GLM were classified into five groups based on the initial treatment methods they underwent, which included observation (n = 8), antibiotics (n = 3), steroid (n = 13), drainage (n = 14), and surgical excision (n = 12). The treatment processes in each group were examined and their clinical characteristics, treatment processes, and results were analyzed respectively. RESULTS: Success rates with each initial treatment were observation, 87.5%; antibiotics, 33.3%; steroids, 30.8%; drainage, 28.6%; and surgical excision, 91.7%. In most cases of observation, the lesions were small and the symptoms were mild. A total of 23 patients underwent surgical excision during treatment. Surgical excision showed particularly fast recovery, high success rate (90.3%) and low recurrence rate (8.7%). CONCLUSION: The clinical course of GLM is complex and the outcome of each treatment type are variable. Surgery may play an important role when a lesion is determined to be mass-forming or appears localized as an abscess pocket during breast examination or imaging study.
Abscess ; Anti-Bacterial Agents ; Breast ; Drainage ; Female ; Granulomatous Mastitis ; Humans ; Mastitis ; Recurrence ; Steroids