Normal Ambulatory 24-Hour Esophageal pH Values in Koreans -A Multicenter Study-

Ambulatory 24-hr esophageal pH monitoring is considered the gold standard for diagnosing gastroesophageal reflux disease. The aim of this study was to establish normal values for gastroesophageal acid exposure in healthy Koreans. Fifty healthy volunteers (24 males and 26 females; mean age, 45 yr) without reflux symptoms and without reflux esophagitis or hiatal hernia on upper endoscopy underwent ambulatory 24-hr esophageal pH monitoring after esophageal manometry. The 95th percentiles for the reflux parameters were: the percent total time pH <4, 3.7%; the percent upright time pH <4, 5.7%; the percent supine time pH <4, 1.0%; the number of reflux episodes with pH <4, 76.5; the number of reflux episodes with pH <4 for >5 min, 1.5; the duration of the longest episode, 12.5 min; and the composite score, 14.2. Age and gender were not associated with any of the pH parameters. In conclusion, physiological gastroesophageal reflux occurs in healthy Koreans. These normal esophageal pH values will provide reference data for clinical and research studies in Korea

Clinical and Microbiologic Investigation of an Expedited Peri-implantitis Dog Model: An Animal Study

Background: Animal studies are pivotal in allowing experimentation to identify efficacious treatment protocols for resolution of peri-implantitis. The purpose of this investigation was to characterize an expedited dog peri-implantitis model clinically, radiographically, and microbiologically. Methods: Eight hound dogs underwent extractions (week 0) and implant (3.3 × 8.5 mm) placement with simultaneous surgical defect creation and ligature placement for induction of peri-implantitis (week 10). Ligatures were replaced at 6 weeks (week 16) and removed after 9 weeks (week 19) when supporting bone loss involved approximately 50% of the peri-implant bone. Microbial samples from the defects and healthy control implant sites collected at week 19 were analyzed utilizing a microarray. Clinical measures of inflammation were obtained and radiographic bone loss was measured from periapical radiographs. Radiographic depth and width measurements of bony defect were repeated at weeks 10 (baseline), 16, and 19. Canonical analysis of principal coordinates was used to visualize overall differences in microbial abundance between peri-implantitis and healthy implants. Results: This accelerated disease protocol led to intrabony defect creation with a mean depth and width of 4.3 mm and 3.5 mm, respectively after 9 weeks of ligature placement. Microbial identification revealed 59 total bacteria in peri-implant sites, 21 of which were only present in peri-implant sites as compared to healthy controls. Overall microbial beta diversity (microbial between-sample compositional diversity) differed between peri-implantitis and healthy implants (p = 0.009). Conclusions: Within the limitations of this study, this protocol led to expedited generation of peri-implant defects with a microbial profile indicative of a shift to disease and defect patterns conducive to regenerative treatment. However, the possibility of potential spontaneous resolution of lesions due to the lack of a chronicity interval as compared to chronic disease models need to be further clarified and considered during preclinical peri-implantitis model selection

Association of Abdominal Obesity with Atherosclerosis in Type 2 Diabetes Mellitus (T2DM) in Korea

The aim of this study was to investigate the relationship between obesity, insulin resistance and atherosclerosis in type 2 diabetes mellitus (T2DM) patients. Total 530 patients with T2DM were included. To evaluate the severity of atherosclerosis, we measured the coronary artery calcification (CAC) score, intima-media thickness (IMT) of the common carotid artery, and the ankle-brachial pressure index (ABPI). Subjects were classified according to body mass index (BMI), a marker of general obesity, and waist-to-hip ratio (WHR), a marker of regional obesity. The insulin sensitivity index (ISI) was measured by the short insulin tolerance test. All subjects were classified into four groups, according to BMI: the under-weight group, the normal-weight (NW) group, the over-weight (OW) group, and the obese (OB) group. WHR and systolic blood pressure, triglycerides (TG), HDL-cholesterol (HDL-C), free fatty acids (FFA), fibrinogen, and fasting c-peptide levels were significantly different between BMI groups. TG, HDL-C, FFA, fibrinogen and ISI were significantly different between patients with and without abdominal obesity. In the OW group as well as in the NW group, carotid IMT, ABPI and CAC score were significantly different between patients with and without abdominal obesity. This study indicates that abdominal obesity was associated with atherosclerosis in T2DM patients

Prognostic Significance of Multidrug Resistance Gene 1 (MDR1), Multidrug Resistance-related Protein (MRP) and Lung Resistance Protein (LRP) mRNA Expression in Acute Leukemia

The prognostic significance of multidrug resistance (MDR) gene expression is controversial. We investigated whether multidrug resistance gene 1 (MDR1), multidrug resistance-related protein (MRP) and lung resistance protein (LRP) mRNA expression are associated with outcomes in acute leukemia patients. At diagnosis we examined MDR1, MRP and LRP mRNA expression in bone marrow samples from 71 acute leukemia patients (39 myeloid, 32 lymphoblastic) using nested RT-PCR. The expression of each of these genes was then expressed as a ratio in relation to β-actin gene expression, and the three genes were categorized as being either 0, 1+, 2+ or 3+. MDR1, MRP and LRP mRNA expression was detected in 23.9%, 83.1% and 45.1%, respectively. LRP mRNA expression was significantly associated with resistance to induction chemotherapy in acute leukemia patients, and in the AML proportion (p=0.02 and p=0.03, respectively). MRP and high MDR1 mRNA expression was associated with poorer 2-yr survival (p=0.049 and p=0.04, respectively). Patients expressing both MRP and LRP mRNA had poorer outcomes and had worse 2-yr survival. The present data suggest that MDR expression affects complete remission and survival rates in acute leukemia patients. Thus, determination of MDR gene expression at diagnosis appears likely to provide useful prognostic information for acute leukemia patients

Patterns of Recurrence after Breast-Conserving Treatment for Early Stage Breast Cancer by Molecular Subtype

Purpose: To study clinical features and patterns of recurrence after breast-conserving treatment (BCT) for three molecular subtypes of early stage breast cancer. Methods: The sample studied included 596 patients with T1-2N0-1 breast cancer who received BCT. Three groups were defined by receptor status. Luminal: estrogen receptor (ER) or progesterone receptor (PR) positive; triple negative (TN): ER, PR, and epidermal growth factor receptor-2 (HER2) receptor negative; and HER2 overexpressing: ER and PR negative but HER2 receptor positive. Results: The number of patients in each group was 408 (68.5%), 105 (17.6%), and 83 (13.9%), respectively. The median follow-up period was 79 months. The TN and HER2 subtypes occurred in younger patients (p=0.0007) and had higher nuclear grade and poorer histologic grade (p&lt;0.0001 and 0.0071, respectively). During the follow-up period, locoregional recurrence was detected as th

A Case of Primary Adrenal Diffuse Large B-cell Lymphoma Achieving Complete Remission with Rituximab-CHOP Chemotherapy

Primary adrenal lymphoma is a very rare extranodal lymphoma; its clinical features consist of a high incidence of bilateral adrenal involvement and diffuse large B-cell lymphoma. We report a patient with primary bilateral adrenal diffuse large B-cell lyphoma who achieved complete remission with R-CHOP (rituximab-cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy. A 52-yr-old man presented with fever and progressive fatigue for 3 months. Computed tomography (CT) scans of the abdomen and pelvis demonstrated large bilateral adrenal masses, and a needle biopsy of the left adrenal mass revealed diffuse large B-cell lymphoma. After 6 cycles of R-CHOP chemotherapy, CT scans showed no residual disease. To our knowledge, this is the second report to date of a patient with primary bilateral adrenal diffuse large B-cell lymphoma who achieved complete remission using R-CHOP chemotherapy