Colon Polyp Detection in Primary Health Care Institutions of Korea: Detection Rate and Issues with Following the Guidelines / 대한소화기학회지

Background/Aims@#There have been few multicenter studies on colonic polyps conducted by primary medical institutions. This study examined the detection rate of colonic polyps in primary health care institutions and the related factors while following the guidelines. @*Methods@#The medical records of 14,029 patients who underwent colonoscopy between January-June 2020 at 40 primary medical institutions in Korea were analyzed. High-risk adenoma was defined as advanced adenoma, carcinoma, or ≥3 adenomas. @*Results@#Most patients (71.2%) aged ≥50 years underwent re-colonoscopy within 5 years (51.3%) for diagnostic purposes (61.3%) in Korean primary medical institutions. The detection rates of colon polyps, adenoma, advanced adenoma, high-risk adenoma, and carcinoma was 59.9%, 38.9%, 5.9%, 11.4%, and 0.3% in all subjects and 59.8%, 37.5%, 8.5%, 12.9%, and 0.3% in average-risk patients, respectively. The incidences of adenoma in average-risk patients increased significantly with age (30s/40s/50s: 20.1%/29.4%/43% for adenoma, 4.4%/6.7%/10.3% for advanced adenoma, and 5.6%/9.5%/14.6% for high-risk adenoma; p<0.05). Before 50 years of age, high-risk adenoma was detected in 9.1% of patients in the first-time screening group, and the significant risk factors were being male and ≥40 years of age. The detection rate of high-risk adenoma in the normal index colonoscopy group within 5 years was 9.0%. The significant risk factors included older age, male sex, positive fecal occult blood test, stool form changes, and nonspecific symptoms (gas and indigestion). @*Conclusions@#More colonic adenoma studies targeting real-world clinical practice will be needed to revise the Korean guidelines for colorectal cancer screening and surveillance.

Urinary Biomarkers for Neurodegenerative Diseases

Global incidence of neurodegenerative diseases (NDDs) such as Alzheimer’s disease (AD) and Parkinson’s disease (PD) is rapidly increasing, but the diagnosis of these diseases at their early stage is challenging. Therefore, the availability of reproducible and reliable biomarkers to diagnose such diseases is more critical than ever. In addition, biomarkers could be used not only to diagnose diseases but also to monitor the development of disease therapeutics. Urine is an excellent biofluid that can be utilized as a source of biomarker to diagnose not only several renal diseases but also other diseases because of its abundance in invasive sampling. However, urine was conventionally regarded as inappropriate as a source of biomarker for neurodegenerative diseases because it is anatomically distant from the central nervous system (CNS), a major pathologic site of NDD, in comparison to other biofluids such as cerebrospinal fluid (CSF) and plasma. However, recent studies have suggested that urine could be utilized as a source of NDD biomarker if an appropriate marker is predetermined by metabolomic and proteomic approaches in urine and other samples. In this review, we summarize such studies related to NDD.

Mannosylerythritol lipids ameliorate ultraviolet A-induced aquaporin-3 downregulation by suppressing c-Jun N-terminal kinase phosphorylation in cultured human keratinocytes

Mannosylerythritol lipids (MELs) are glycolipids and have several pharmacological efficacies. MELs also show skin-moisturizing efficacy through a yet-unknown underlying mechanism. Aquaporin-3 (AQP3) is a membrane protein that contributes to the water homeostasis of the epidermis, and decreased AQP3 expression following ultraviolet (UV)-irradiation of the skin is associated with reduced skin moisture. No previous study has examined whether the skin-moisturizing effect of MELs might act through the modulation of AQP3 expression. Here, we report for the first time that MELs ameliorate the UVA-induced downregulation of AQP3 in cultured human epidermal keratinocytes (HaCaT keratinocytes). Our results revealed that UVA irradiation decreases AQP3 expression at the protein and messenger RNA (mRNA) levels, but that MEL treatment significantly ameliorated these effects. Our mitogen-activated protein kinase inhibitor analysis revealed that phosphorylation of c-Jun N-terminal kinase (JNK), but not extracellular signal-regulated kinase or p38, mediates UVA-induced AQP3 downregulation, and that MEL treatment significantly suppressed the UVA-induced phosphorylation of JNK. To explore a possible mechanism, we tested whether MELs could regulate the expression of peroxidase proliferator-activated receptor gamma (PPAR-γ), which acts as a potent transcription factor for AQP3 expression. Interestingly, UVA irradiation significantly inhibited the mRNA expression of PPAR-γ in HaCaT keratinocytes, whereas a JNK inhibitor and MELs significantly rescued this effect. Taken together, these findings suggest that MELs ameliorate UVA-induced AQP3 downregulation in HaCaT keratinocytes by suppressing JNK activation to block the decrease of PPAR-γ. Collectively, our findings suggest that MELs can be used as a potential ingredient that modulates AQP3 expression to improve skin moisturization following UVA irradiation-induced damage.

Screening and Evaluation of Streptomyces Species as a Potential Biocontrol Agent against a Wood Decay Fungus, Gloeophyllum trabeum

Two-hundred and fifty-five strains of actinomycetes isolated from soil samples were screened for their antagonistic activities against four well-known wood decay fungi (WDF), including a brown rot fungus, Gloeophyllum trabeum and three white rot fungi Donkioporia expansa, Trametes versicolor, and Schizophyllum commune. A dual culture assay using culture media supplemented with heated or unheated culture filtrates of selected bacterial strains was used for the detection of their antimicrobial activity against four WDF. It was shown that Streptomyces atratus, S. tsukiyonensis, and Streptomyces sp. greatly inhibited the mycelial growth of the WDF tested compared with the control. To evaluate the biocontrol efficacy of S. atratus, S. tsukiyonensis, and Streptomyces sp., wood blocks of Pinus densiflora inoculated with three selected Streptomyces isolates were tested for weight loss, compression strength (perpendicular or parallel to the grain), bending strength, and chemical component changes. Of these three isolates used, Streptomyces sp. exhibited higher inhibitory activity against WDF, especially G. trabeum, as observed in mechanical and chemical change analyses. Scanning electron microscopy showed that cell walls of the wood block treated with Streptomyces strains were thicker and collapsed to a lesser extent than those of the non-treated control. Taken together, our findings indicate that Streptomyces sp. exhibits the potential to be used as a biocontrol agent for wood decay brown rot fungus that causes severe damage to coniferous woods.

Guidelines of cleaning and disinfection in gastrointestinal endoscope for clinicians

Gastrointestinal endoscopy plays an important diagnostic and therapeutic role in the field of gastrointestinal disease. As endoscopies have become more common due to the nationwide screening program for digestive cancer and an increasing interest in health among the general public, the risk of infection transmission between patients has emerged as a clinical challenge. Although endoscopes can become highly contaminated with secretions and blood during use, the thorough reprocessing of an endoscope before it is reused in subsequent patients can be difficult due to its complicated structure. Although the incidence of endoscopy-associated infections has been reported to be extremely low, compelling evidence suggests that the actual incidence is underestimated. It has been well established that endoscopes reprocessed appropriately, in accordance with standard guidelines, have no risk of infection transmission. Although revised guidelines for endoscope reprocessing were released in Korea in 2015, suboptimal infection prevention practices during endoscope reprocessing have been reported. Under these circumstances, the Korean Society of Digestive Endoscopy developed the ‘Guidelines of cleaning and disinfection in gastrointestinal endoscope for clinicians’ based on the currently available evidence. These guidelines provide accurate and updated information on reprocessing techniques, and can help improve the quality of reprocessing and compliance by health care personnel. As a result, infection control during gastrointestinal endoscopies can be expected to be achieved in Korea.

Guidelines of cleaning and disinfection in gastrointestinal endoscope for clinicians

Gastrointestinal endoscopy plays an important diagnostic and therapeutic role in the field of gastrointestinal disease. As endoscopies have become more common due to the nationwide screening program for digestive cancer and an increasing interest in health among the general public, the risk of infection transmission between patients has emerged as a clinical challenge. Although endoscopes can become highly contaminated with secretions and blood during use, the thorough reprocessing of an endoscope before it is reused in subsequent patients can be difficult due to its complicated structure. Although the incidence of endoscopy-associated infections has been reported to be extremely low, compelling evidence suggests that the actual incidence is underestimated. It has been well established that endoscopes reprocessed appropriately, in accordance with standard guidelines, have no risk of infection transmission. Although revised guidelines for endoscope reprocessing were released in Korea in 2015, suboptimal infection prevention practices during endoscope reprocessing have been reported. Under these circumstances, the Korean Society of Digestive Endoscopy developed the ‘Guidelines of cleaning and disinfection in gastrointestinal endoscope for clinicians’ based on the currently available evidence. These guidelines provide accurate and updated information on reprocessing techniques, and can help improve the quality of reprocessing and compliance by health care personnel. As a result, infection control during gastrointestinal endoscopies can be expected to be achieved in Korea.

Usefulness of Serum Thymidine Kinase 1 as a Biomarker for Aggressive Clinical Behavior in B-cell Lymphoma

BACKGROUND: The cell cycle-dependent enzyme thymidine kinase 1 (TK1) is known to increase during cancer cell proliferation and has been reported as a prognostic marker for various hematologic malignancies and solid tumors. This study aimed to determine the reference interval in Korean healthy controls and to evaluate the usefulness of TK1 as a biomarker for aggressive clinical behavior in B-cell lymphoma patients. METHODS: We enrolled 72 previously untreated patients with B-cell lymphoma and 143 healthy controls. Serum TK1 levels were measured by chemiluminescence immunoassay (Liaison(R), DiaSorin, USA). We established the reference intervals in healthy controls. The diagnostic performance of serum TK1 was studied using receiver operating characteristic (ROC) analysis, and the correlation between the cutoff level for serum TK1 and clinical characteristics of B-cell lymphoma was evaluated. RESULTS: The reference range (95th percentile) of serum TK1 in healthy controls was 5.4-21.8 U/L. There was a clear difference in TK1 levels between patients with B-cell lymphoma and healthy controls (40.6+/-68.5 vs. 11.8+/-4.4 U/L, P or =15.2 U/L) correlated with the advanced clinical stage (P<0.001), bone marrow involvement (P=0.013), international prognostic index score (P=0.001), lactate dehydrogenase level (P=0.001), low Hb level (<12 g/dL) (P=0.028), and lymphocyte count (P=0.023). CONCLUSIONS: The serum TK1 level could serve as a useful biomarker for aggressive clinical behavior in B-cell lymphoma patients.

A Rare Case of Pediatric T Lymphoblastic Leukemia With t(11;17)(q23;q21) Involving Mixed-Lineage Leukemia Gene Rearrangement

No abstract available.

The Efficacy, Longevity, and Safety of Combined Radiofrequency Treatment and Hyaluronic Acid Filler for Skin Rejuvenation

BACKGROUND: Recent advances in hyaluronic acid (HA) fillers and radiofrequency (RF) devices have been made in the context of skin rejuvenation and cosmetic surgery. Moreover, combination regimens with both techniques are currently being developed. OBJECTIVE: The present study was designed to examine the clinical and histologic effects of a new needle that incorporates an RF device for HA injections. METHODS: A new intradermal needle RF device (INNOfill; Pacific Pharma, Korea) was assessed in the present study. In the animal arm, procollagen production was measured by using enzyme-linked immunosorbent assay, the filler volume was quantified by incorporating a dye with filler, and the filler distribution was assessed through the changes in tissue structure. In the human arm, the efficacy of the combination regimen was assessed by using the wrinkle severity rating scale (WSRS). RESULTS: In the animal study, RF treatment increased procollagen production in a time-dependent fashion. The total volume was significantly increased with the RF treatment when compared with the filler injections alone, and lasted for up to 7 weeks after treatment. Additionally, the filler distribution was reduced in animals treated with RF when compared with the untreated group. In the human study, the nasolabial folds of subjects treated with RF before filler injections exhibited a significantly greater change in the WSRS score from baseline when compared with the nasolabial folds treated with filler injections alone. CONCLUSION: A new device incorporating RF treatment before HA filler injection may represent a biocompatible and long-lasting advance in skin rejuvenation.

The effect of bonded resin surface area on the detachment force of lingual bonded fixed retainers: An in vitro study / 대한치과교정학회지

OBJECTIVE: The aims of this study were to evaluate the relationship between the detachment force and bonding resin surface are and to determine the resin bonding surface area that would provide adequate bonding strength with minimum resin volume. METHODS: One hundred and sixty human premolars were randomly divided into 4 groups of 40 teeth each. The diameter of the resin surface area in each group was as follows: group 1, 1.5 mm; group 2, 2.5 mm; group 3, 3.5 mm; and group 4, 4.5 mm. Respond Dead Soft straight (length 0.0175 inch) was used to fabricate the retainers, and Transbond(TM) XT was used to fix the retainers to the tooth surfaces. A pair of teeth was embedded in acrylic blocks for each specimen. Thus, each group comprised 20 samples. Fixed retainers were bonded to the teeth, and vertical force was applied at the middle of wire. The force was measured using a universal testing machine. RESULTS: The mean value of detachment force was the highest for group 4 (102.38 +/- 2.92 N), followed by group 3 (63.54 +/- 2.21 N), group 2 (51.95 +/- 1.61 N), and group 1 (24.14 +/- 1.38 N). CONCLUSIONS: The detachment force of lingual fixed retainers was significantly affected as the area of the resin bonding surface increased. Considering the minimum bonding strength of brackets, a resin bonding surface area with a diameter of 3.5 mm would provide adequate bonding strength.

Comparison of Serum Fibrin-Fibrinogen Degradation Products with Carcinoembryonic Antigen as Biomarkers for Colon Cancer / 임상검사와정도관리

BACKGROUND: Colon cancer is the second most common cancer in males and fourth most common in females in Korea. The levels of serum fibrin-fibrinogen degradation products (FDP) are elevated in many malignancies due to haemostatic alterations resulting from carcinogenesis. We compared serum FDP with carcinoembryonic antigen (CEA) to assess whether FDP has a diagnostic value for colon cancer. METHODS: A total of 177 serum samples from 95 colon cancer patients and 82 healthy controls were provided by the Korea Cancer Center Hospital biobank. Serum FDP levels were measured using the DR-70 detection kits (AMDL, USA) and the levels of serum CEA were measured using the Roche E170 Analytics (Roche Diagnostics, Germany). RESULTS: The mean serum FDP and serum CEA levels were significantly higher in the cancer patient group (FDP, 1.65+/-1.44 microg/mL; range, 0.36 to 9.48; CEA, 99.99+/-321.74 ng/mL; range, 1.46 to 2,170.00) than in the control group (FDP, 0.58+/-0.46 microg/mL; range, 0.02 to 3.27, P<0.05; CEA, 1.66+/-1.18 ng/mL; range, 0.20 to 6.38, P<0.05). The receiver operating characteristic curve for FDP showed 80% clinical sensitivity and 83% specificity with an optimal cut-off of 0.81 microg/mL, while that for CEA exhibited 84% sensitivity and 94% specificity with a cut-off of 3.51 ng/mL. The area under the curve was 0.87 and 0.96 for serum FDP and CEA, respectively. A combination of the two markers showed 90% clinical sensitivity and 92% specificity for colon cancer. CONCLUSIONS: The diagnostic sensitivity for colon cancer was increased by using a combination of FDP and CEA.

Utilization of Mean Peroxidase Index for Discrimination of Pseudoneutropenia

BACKGROUND: Autoanalyzer ADVIA2120 uses intracellular peroxidase concentration to perform white blood cell (WBC) differential. Therefore, in specimens containing neutrophils with low peroxidase concentration, neutrophils can be miscounted as monocytes or large unstained cells resulting in pseudoneutropenia. Myeloperoxidase deficiency can be detected by the mean peroxidase index (MPXI). The aims of this study are to establish the reference interval of MPXI and define a cut off value for manual slide review to discriminate pseudoneutropenia. METHODS: We calculated reference intervals as mean+/-2SD according to the indirect method of CLSI C28-A3 guideline from MPXI data of 5,802 individuals who took routine health checkup from April 2010 to June 2012. We performed manual slide review on specimens with low MPXI and compared neutrophil differential count of manual method with that of autoanalyzer. When neutrophil differential in manual slide review was >20%P higher than autoanalyzer result, it was regarded as a pseudoneutropenia. We performed ROC analysis using the MPXI results of samples with and without pseudoneutropenia to define a cutoff to discriminate pseudoneutropenia. RESULTS: The reference intervals of MPXI in total population, male, and female were -4.9 to 7.5, -5.5 to 7.3, and -4.5 to 7.5, respectively. The mean value of MPXI was significantly higher in female than in male and there was no difference by age. Twenty-two pseudoneutropenia samples from 7 patients were identified. ROC analysis yielded cutoff value of -20.7 with 94.9% of sensitivity and 77.3% of specificity. CONCLUSIONS: MPXI may be used in the manual slide review guideline for detecting pseudoneutropenia.

A Case of Hepatosplenic T-cell Lymphoma Diagnosed by Bone Marrow Examination

Hepatosplenic T-cell lymphoma (HSTL) is a condition in which lymphoma cells infiltrate the sinusoids of the liver, spleen, and bone marrow, without lymph node involvement. We encountered a case of hepatosplenic T-cell lymphoma in a Vietnamese woman. The patient was hospitalized with epigastric pain and nausea. Splenomegaly and multiple poorly defined, low-attenuating nodular lesions in the liver were visualized on computed tomography (CT), and thrombocytopenia was noted. The lymph nodes were not significantly enlarged. Splenic biopsy could not be performed because of severe thrombocytopenia. Neoplastic lymphoid cells were present in bone marrow aspirates. Bone marrow sections revealed infiltration of CD3(+) and CD20(-) neoplastic lymphoid cells in the sinusoids. A clonality assay (IdentiClone T-Cell Receptor Delta Gene Clonality Assay; Invivoscribe Technologies, USA) showed gene rearrangements in the T-cell receptor delta gene. Thus, we made a confirmatory diagnosis of HSTL. When splenic biopsy is not available, bone marrow aspirates and clonality assessment may become useful diagnostic tools.

A Case of Heterozygous alpha(+)-Thalassemia Diagnosed in a Korean Family by Using Multiplex Ligation-Dependent Probe Amplification / 임상검사와정도관리

Alpha-thalassemia (alpha-thalassemia), which is prevalent in the Mediterranean region, is caused by deficient synthesis of the alpha-globin chains. It is commonly caused by HBA1 and/or HBA2 gene deletion and is diagnosed by DNA sequence analysis. The proband was a 38-year-old woman who was found to have microcytic and hypochromic anemia on a routine health checkup. Results of the Hb electrophoresis (EP) and direct sequencing of the HBA1 and HBA2 genes were found to be normal. As multiplex ligation-dependent probe amplification (MLPA) for the HBA1 and HBA2 genes revealed heterozygous deletion, she was diagnosed with heterozygous alpha+-thalassemia. Although routine laboratory tests revealed similar findings in the proband's father, brother and niece, MLPA revealed heterozygous deletions of the HBA1 or HBA2 gene in her brother and niece. In summary, we report a case of heterozygous alpha+-thalassemia in a Korean family that was detected by MLPA. We recommend that patients with suspected hemoglobinopathies should be followed-up further with MLPA, especially when Hb EP shows a normal pattern.

Clinical Significance of Oligoclonal Bands in Patients with Multiple Myeloma after Autologous Stem Cell Transplantation

BACKGROUND: Oligoclonal bands or isotype switch detectable by serum immunofixation electrophoresis (IFE) has been reported following chemotherapy and stem cell transplantation in patients with multiple myeloma (MM). We studied the significance of oligoclonal bands appearing after chemotherapy and autologous stem cell transplantation (ASCT) in Korean MM patients, and its impact on relapse. And we investigated the serial serum free light chain (FLC) ratio to establish its possible relationship with the relapse of MM. METHODS: We conducted a retrospective analysis of the serial serum IFE and FLC ratio in 16 MM patients treated with chemotherapy and ASCT. RESULTS: Eleven out of 16 patients (68.8%) had oligoclonal bands with or without isotype switch after ASCT and the median interval from transplantation was 2.0 months. And relapse or persistence rate of monoclonal gammopathy was lower in patients with oligoclonal bands (27.3% vs. 60.0%), though without statistical significance (P=0.299). In eight patients who developed oligoclonal bands and did not relapse, the serial serum FLC ratio was normal in range. But one patient who developed oligoclonal bands and showed increase of plasma cells in bone marrow, the serial serum FLC ratio was abnormal in range. CONCLUSIONS: The occurrence of oligoclonal bands after chemotherapy and ASCT in Korean MM patients is not significantly associated with adverse consequence of relapse or persistence of monoclonal gammopathy. Therefore oligoclonal bands may be not bad prognostic criterion. And the measurement of serum FLC ratio may be a useful indicator to predict relapse in MM patients who developed oligoclonal bands.

Type Distribution of Unexpected Red Cell Antibodies in Patients with Malignancy / 대한수혈학회지

BACKGROUND: Performance of antibody screening and identification tests before blood transfusion is important because the unexpected presence of red cell antibodies may cause hemolytic transfusion reactions. Many patients with malignancy undergo transfusion in order to overcome pancytopenia due to disease itself or chemotherapy. We investigated the type distribution of unexpected red cell antibodies in cancer patients and compared our results with those of other institutions. METHODS: From January 2008 to June 2011, 30,989 serum samples were screened using a LISS/Coombs card and ID-DiaCell I, II (DiaMed AG, Morat, Switzerland). Data-Cyte Plus Reagent Red Blood Cells (Medion Diagnostics, Dudingen, Switzerland) were used in performance of antibody identification tests. RESULTS: Out of 30,989 serum samples, 180 cases (0.58%) showed screening-positive results, and unexpected antibodies were identified in 72 cases. The type of unexpected antibody observed most often in cancer patients was a member of the Rh antibody group, anti-E in 17 cases (29.8%), followed by anti-Lea in five cases (8.8%) and anti-e in three cases (5.3%). While Rh group antibodies were observed in the colon cancer group, non-Rh group antibodies were observed in the rectal cancer group. And, in the genitourinary cancer group, Lewis group antibodies were more frequently detected than others. CONCLUSION: Findings from our study demonstrated a type distribution of unexpected red cell antibodies that was similar to those reported in previous studies. Compared with non-cancerous patients, no difference in type distribution of unexpected red cell antibodies was observed in cancer patients. Some antibodies were frequently observed in certain cancer groups. Further comprehensive research on unexpected antibodies based on location or histologic type of cancer is needed.

A Case of a 63-bp Deletion in the mpt64 Gene of Mycobacterium tuberculosis Strains Which Showed False Negativity in the Immunochromatographic Assay / 대한임상미생물학회지

Mycobacterium tuberculosis complex (MTBC) is discriminated from non-tuberculous mycobacteria (NTM) via an immunochromatographic assay (ICA) which is based on the reactions of monoclonal antibodies against MPT64, one of the predominant proteins excreted by MTBC. Recently, the authors of the present study discovered SD TB-negative Mycobacterium tuberculosis strains. In addition, sequence analysis of the mpt64 genes in these strains was performed and showed a deletion of 63 bp from nucleotides 196 to 258. In cases of MPT64-negative mycobacterium, the authors recommend performing TB PCR for correct diagnosis.

Late-onset Neutropenia Following Rituximab Therapy as a Treatment of Diffuse Large B-cell Lymphoma: A Single Institution Study / 대한진단검사의학회지

BACKGROUND: Late-onset neutropenia (LON) following rituximab therapy has been reported in recent years. However, its incidence has not been reported in Korea. The aim of this study is to investigate the incidence of LON after rituximab therapy in Korean patients with diffuse large B-cell lymphoma (DLBCL). METHODS: Ninety-eight cases of DLBCL treated with rituximab between 2004 and 2008 were evaluated. We identified LON as defined by the neutrophil count of <1.5x10(9)/L without apparent cause after the recovery of neutrophil count following rituximab therapy. Bone marrow aspiration and biopsy specimens at the time of neutropenia were available for retrospective review in only 5 of the patients. RESULTS: LON was observed in 15 (15.3%) of the 98 patients. In the bone marrow specimens of the 5 patients, promyelocytes were relatively increased and the maturation index of the granulopoiesis was 2:1-3:1, which reflects maturation arrest. CONCLUSIONS: The incidence of LON following rituximab therapy was 15.3% in Korean patients with DLBCL. Although there are several hypotheses about the causative mechanisms of LON, we suggest that maturation arrest at the promyelocyte stage of granulopoiesis may be one of the mechanisms involved in the development of LON.

A Case of del(16)(q22) in a Patient with Acute Myeloid Leukemia with Complex Karyotype / 대한진단검사의학회지

Inversion of chromosome 16 [inv(16)(p13.1q22)] and t(16;16)(p13.1;q22) are associated with acute myelomonocytic leukemia (AMML) with eosinophilia and a favorable prognosis. On the other hand, patients with del(16)(q22) usually present with MDS or chronic myelomonocytic leukemia (CMML), which can evolve to AMML without eosinophilia, and this chromosomal aberration is associated with older age, a complex karyotype, and a poor prognosis. We report a case of AML with del(16)(q22) which showed a complex karyotype, absence of eosinophilia in bone marrow study and a poor response to chemotherapy.

Development of Indicators to Assess the Stability of Remnant Blood Samples Stored in a Biobank: Experience at One Institution / 대한진단검사의학회지

BACKGROUND: One of the major concerns with biobanking is the absence of standard operating procedures to eliminate pre-analytical variation arising from sample collection, preparation, and storage. Currently, there is a lack of tools to carry out quality control procedures for stored blood samples. The aim of this study is to assess the quality of stored blood samples in our biobank and to suggest appropriate indicators for their quality control. METHODS: The stored blood samples that we tested have been registered into our biobank since 2003. These were transferred to our biobank after carrying out routine requested tests, because the samples would have otherwise been discarded. For the purpose of quality control, we analyzed the concentrations and the integrity of DNA and RNA extracted from the stored samples and tested the levels of several serum proteins; the results were compared with the corresponding pre-storage levels. RESULTS: A total of 19 samples were stored from 2006 to 2009. Of the 22 samples stored between 2003 and 2005, 50% showed complete DNA integrity. However, sufficient RNA integrity was noted in only 1 sample stored as recently as 2009. High blood urea nitrogen levels were also noted in the stored sera, but the increase did not correlate to the duration of storage. CONCLUSIONS: The amount and integrity of nucleic acids extracted from stored blood samples are potential indicators that can be used for quality control. A guideline for the quality assessment of stored blood samples in a biobank is urgently needed.