Performance Evaluation and Measurement Uncertainty Determination of the New Version of the Abbott ARCHITECT 25-OH Vitamin D 5P02 Assay.

Objectives: We evaluated performance and measurement uncertainty of the newly released ARCHITECT 25-OH vitamin D 5P02 assay (Abbott Diagnostics, Abbott Park, IL). Methods: In total, 300 samples were used to compare the results from ELECSYS Vitamin D Total (Roche Diagnostics, Mannheim, Germany) and ADVIA Centaur Vitamin D Total (Siemens, Tarrytown, NY). To quantify the measurement uncertainty, 25 samples and four levels of standard reference material (SRM) were measured using isotope dilution-liquid chromatography-tandem mass spectrometry according to international guidelines. Results: The results of the ARCHITECT assay were equivalent to other immunoassays, but correlation coefficients were lower than the recommended criterion. SRM level 2 was considered adequate for uncertainty estimation, and the expanded measurement uncertainty of the ARCHITECT assay was 4.2%, which was superior to the other two assays. Conclusions: The restandardized ARCHITECT assay has acceptable performance in a clinical setting. However, there is still a need for further standardization of total vitamin D measurement among the automated immunoassays.

Age-related Reference Intervals for Total Collagen-I-N-terminal Propeptide in Healthy Korean Population.

BACKGROUND: Procollagen type I N-terminal propeptide (PINP) is one of the most clinically useful bone formation biomarkers. Therefore, the purpose of this study was to independently evaluate the performance of automated total PINP assay and established age- and gender-specific reference intervals for PINP in healthy Korean population. METHODS: The imprecision, linearity, and detection capability of Elecsys total PINP assay was determined and reference interval was established using 599 serums from Korean population with normal bone mineral densities based on bone densitometry. Age groups were divided into 20s, 30s, 40s, 50s, 60s and over. RESULTS: Elecsys total PINP had excellent performance in imprecision, linearity, and detection capability. When partitioning age groups in Korean male and female populations, there was significant difference in total PINP between different age groups. In male populations, PINP level was decreased with increasing age, then it remained steady after middle-age. In female populations, there was a decreasing tendency similar to that in the male population with a sharp increase in the 50 to 59 age group. CONCLUSIONS: Elecsys total PINP assay showed precise and reliable performance in our study. We established age-related PINP reference intervals for Korean male and female population with normal bone mineral densities.

Measurement uncertainty of platelet concentration using the Sysmex XN automated hematology analyzer.

We estimated the measurement uncertainty (MU) of platelet concentration measured using the Sysmex XN system with two reference platelet counting methods described by DIN 58932-5 (PTB method) and the International Council for Standardization in Haematology (ICSH method). Ten blood samples were used to estimate and compare the MU of the XN system, and 30 samples were used to compare the methods. The standard uncertainty of the reference method was significantly higher for the ICSH method; the PTB method showed higher platelet concentrations than the ICSH method. When applying different methods with the XN system, optic counting showed higher MU compared to the other methods. There was good correlation among the two reference methods and three automated platelet-counting methods. We evaluated the MU in platelet concentrations measured using an automated hematology analyzer. Our results suggest that using the PTB method for calculating MU of the automated hematology analyzer is superior to the ICSH method because of its lower standard uncertainty.

Prognostic Impact of Lymphocyte Subpopulations in Peripheral Blood after Hematopoietic Stem Cell Transplantation for Hematologic Malignancies.

BACKGROUND: We prospectively evaluated prognostic value of lymphocyte subpopulations in peripheral blood of allogeneic hematopoietic stem cell transplant (HSCT) recipients. METHODS: 113 allogeneic HSCT (47 sibling matched, 37 unrelated matched, 29 haploidentical)-performed patients diagnosed as AML (n = 66), ALL (n = 28), and MDS (n = 19) were prospectively enrolled. 14 lymphocyte subpopulations were quantified by flow cytometry of PB at specific time-points after HSCT, and their prognostic impacts were analyzed. RESULTS: At 1, 2, and 3 months post-HSCT, significant adverse impact on overall survival (OS) and/or event free survival (EFS) was exhibited by low levels of natural killer (NK) cells (≤32 and ≤90/µL at 1 and 2 months on OS and EFS); regulatory T cells (≤1/µL) on EFS at 2 months; and B cells (≤19 and ≤92/µL for OS and EFS at 3 months). At 12 months, low levels of T cells (≤1180/µL), helper/inducer (H/I) T cells (≤250/µL), cytotoxic/suppressor (C/S) T cells (≤541/µL), and NK cells (≤138/µL) were associated with significantly higher risk of relapse. Low levels of T cells (≤879/µL) and C/S T cells (≤541/µL), and high level of naïve thymic T cells (>115/µL) showed a significant association with poor OS; low levels of C/S T cells (≤541/µL) and NK cells (≤138/µL) showed a significant adverse impact on EFS. CONCLUSIONS: Low levels of NK cells, regulatory T cells, and B cells at early stage post-HSCT are adverse prognostic indicators. At late stage, low levels of T cells and their subpopulations, NK cells, and high level of naïve thymic T cells are adverse prognostic indicators. © 2017 International Clinical Cytometry Society.

Measurement Uncertainty in Spine Bone Mineral Density by Dual Energy X-ray Absorptiometry.

BACKGROUND: The purpose of this study was to calculate the measurement uncertainty of the process of bone mineral density (BMD) analysis using dual energy X-ray absorptiometry with traceability. METHODS: Between March 2015 and October 2016, among healthy participants in their 20s and 30s, the study included those who had not taken calcium, vitamin D supplements and steroids and were without a history of osteoporosis, osteopenia and diseases related to osteoporosis. Relational expression of the model was established based on Guide to the Expression of Uncertainty in Measurements and Eurachem and the uncertainty from each factor was evaluated. RESULTS: The combined standard uncertainty was 0.015, while the expanded uncertainty was 0.0298. The factor-specific standard uncertainties that occurred in the process of measuring BMD were 0.72% for the calibration curve, 0.9% for the internal quality control (IQC) using Aluminum Spine Phantom, 0.58% for European Spine Phantom (ESP), and 0.9% for the inspector precision (IP). CONCLUSIONS: The combined standard uncertainty of the spine BMD corrected with ESP was 0.015 when measured at one time and targeting one participant. The uncertainties of the accuracy of the IQC and the IP were higher than that of the other factors. Therefore, there will be a need for establishment of protocols to lower these uncertainties.

Molecular Genealogy of a Mongol Queen's Family and Her Possible Kinship with Genghis Khan.

Members of the Mongol imperial family (designated the Golden family) are buried in a secret necropolis; therefore, none of their burial grounds have been found. In 2004, we first discovered 5 graves belonging to the Golden family in Tavan Tolgoi, Eastern Mongolia. To define the genealogy of the 5 bodies and the kinship among them, SNP and/or STR profiles of mitochondria, autosomes, and Y chromosomes were analyzed. Four of the 5 bodies were determined to carry the mitochondrial DNA haplogroup D4, while the fifth carried haplogroup CZ, indicating that this individual had no kinship with the others. Meanwhile, Y-SNP and Y-STR profiles indicate that the males examined belonged to the R1b-M343 haplogroup. Thus, their East Asian D4 or CZ matrilineal and West Eurasian R1b-M343 patrilineal origins reveal genealogical admixture between Caucasoid and Mongoloid ethnic groups, despite a Mongoloid physical appearance. In addition, Y chromosomal and autosomal STR profiles revealed that the four D4-carrying bodies bore the relationship of either mother and three sons or four full siblings with almost the same probability. Moreover, the geographical distribution of R1b-M343-carrying modern-day individuals demonstrates that descendants of Tavan Tolgoi bodies today live mainly in Western Eurasia, with a high frequency in the territories of the past Mongol khanates. Here, we propose that Genghis Khan and his family carried Y-haplogroup R1b-M343, which is prevalent in West Eurasia, rather than the Y-haplogroup C3c-M48, which is prevalent in Asia and which is widely accepted to be present in the family members of Genghis Khan. Additionally, Tavan Tolgoi bodies may have been the product of marriages between the lineage of Genghis Khan's Borjigin clan and the lineage of either the Ongud or Hongirad clans, indicating that these individuals were members of Genghis Khan's immediate family or his close relatives.

Comparison of Three Different Commercial Kits for the Human Papilloma Virus Genotyping.

BACKGROUND: High-risk type human papilloma virus (HPV) is the most important cause of cervical cancer. Recently, real-time polymerase chain reaction and reverse blot hybridization assay-based HPV DNA genotyping kits are developed. So, we compared the performances of different three HPV genotyping kits using different analytical principles and methods. METHODS: Two hundred positive and 100 negative cervical swab specimens were used. DNA was extracted and all samples were tested by the MolecuTech REBA HPV-ID, Anyplex II HPV28 Detection, and HPVDNAChip. Direct sequencing was performed as a reference method for confirming high-risk HPV genotypes 16, 18, 45, 52, and 58. RESULTS: Although high-level agreement results were observed in negative samples, three kits showed decreased interassay agreement as screening setting in positive samples. Comparing the genotyping results, three assays showed acceptable sensitivity and specificity for the detection of HPV 16 and 18. Otherwise, various sensitivities showed in the detection of HPV 45, 52, and 58. CONCLUSIONS: The three assays had dissimilar performance of HPV screening capacity and exhibited moderate level of concordance in HPV genotyping. These discrepant results were unavoidable due to difference in type-specific analytical sensitivity and lack of standardization; therefore, we suggested that the efforts to standardization of HPV genotyping kits and adjusting analytical sensitivity would be important for the best clinical performance.

Discrepancy between Vitamin D Total Immunoassays due to Various Cross-reactivities.

BACKGROUND: The purpose of this study was to find out the cause of discrepancy between various automated immunoassays for 25-hydroxy-vitamin D (25-[OH]D). METHODS: National Institute of Standards & Technology Standard Reference Material (SRM) 972a is SRM for 25-(OH)D and consists of 4 vials of frozen serum with different concentrations of 25-(OH)D. Each concentration was measured 6 times in 3 different immunoassays: ADVIA Vitamin D Total assay (Siemens Healthcare, Erlangen, Germany), ARCHITECT 25-(OH)D (Abbott Laboratories, Abbott Park, IL, USA), and COBAS Vitamin D Total assay (Roche Diagnostics, Basel, Switzerland). RESULTS: When using the certified reference values of SRM 972a as it is, discarding the cross-reactivity of each immunoassay, for ADVIA, the coefficient of determination (R(2)) as a score of regression analysis was 0.8995 and maximal difference between measured value and certified reference value was 3.6 ng/mL in level 3. The R(2) and maximal differences of ARCHITECT were 0.5377 and 6.9 ng/mL, respectively, in level 4. Those of COBAS were 0.3674 and 22.3 ng/mL, respectively, in level 4. When considering cross-reactivities of each immunoassays to various 25-(OH)D metabolites, the ADVIA had R(2) and maximal difference of 0.9254 and 3.3 ng/mL, respectively, in level 3. For ARCHITECT, the R(2) and maximal differences were 0.7602 and 5.1 ng/mL, respectively, in level 1. Those of COBAS were 0.9284 and 4.9 ng/mL, respectively, in level 1. CONCLUSIONS: The cause of discrepancies between vitamin D immunoassays was mainly on the difference in cross-reactivities to various vitamin D metabolites. The discrepancies can be considerably decreased by considering cross-reactivities of each immunoassay.

Result of Proficiency Test and Comparison of Accuracy Using a European Spine Phantom among the Three Bone Densitometries.

BACKGROUND: Although dual energy X-ray absorptiometry (DXA) is known to standard equipment for bone mineral density (BMD) measurements. Different results of BMD measurement using a number of different types of devices are difficult to use clinical practice. The purpose of this study was to evaluate discrepancy and standardizations of DXA devices from three manufactures using a European Spine Phantom (ESP). METHODS: We calculated the accuracy and precision of 36 DXA devices from three manufacturers (10 Hologic, 16 Lunar, and 10 Osteosys) using a ESP (semi-anthropomorphic). The ESP was measured 5 times on each equipment without repositioning. Accuracy was assessed by comparing BMD (g/cm(2)) values measured on each device with the actual value of the phantom. Precision was assessed by the coefficient of variation (CVsd). RESULTS: Lunar devices were, on average, 22%, 8.3%, and 5% overestimation for low (L1) BMD values, medium (L2), and high (L3) BMD values. Hologic devices were, on average, 6% overestimation for L1 BMD, and 5% and 6.2% underestimation for L2 and L3 BMD values. Osteosys devices was, on average, 12.7% (0.063 g/cm(2)), 6.3% (0.062 g/cm(2)), and 5% (0.075 g/cm(2)) underestimation for L1, L2, and L3, respectively. The mean CVsd for L1-L3 BMD were 0.01%, 0.78%, and 2.46% for Lunar, Hologic, and Osteosys devices respectively. CONCLUSIONS: The BMD comparison in this study demonstrates that BMD result of three different devices are significant different between three devices. Differences of BMD between three devices are necessary to BMD standardization.

Performance evaluation of a DNA chip assay in the identification of major genitourinary pathogens.

BACKGROUND: To prevent the recurrence of genitourinary infections and to reduce the risks of their complications, accurate and rapid diagnosis are required. STDetect® Chip is a DNA chip which allows for the simultaneous detection of 13 major genitourinary pathogens in a single vaginal swab or urine specimen. We evaluated the analytical performance of the STDetect® Chip for detecting target pathogens that commonly cause genitourinary infections. METHODS: The target pathogens of the STDetect® Chip are Chlamydia trachomatis, Candida albicans, Enterococcus faecalis, Gardnerella vaginalis, Mycoplasma hominis, Neisseria gonorrhoeae, Mycoplasma genitalium, Ureaplasma urealyticum, Staphylococcus aureus, Klebsiella pneumoniae, Trichomonas vaginalis, and Herpes simplex virus types 1 and 2. Performance of the STDetect® Chip for the detection of target pathogens was evaluated comparing with the result of direct sequencing and conventional multiplex PCR assay. And precision tests for STDetect® Chip were performed with quality control materials. RESULTS: The STDetect® Chip showed high sensitivities (95.1%-100%), specificities (93.4% to 100%), concordance rates (95.0%-100%), positive predictive values (69.8%-100%), and negative predictive values (93.1%-100%) in its identification of 13 target pathogens. The STDetect® Chip had a particularly excellent concordance rate (96.5%) for the 4 major pathogens, C. albicans, G. vaginalis, M. hominis, and U. urealyticum, compared with direct sequencing. Comparing to multiplex PCR assay, STDetect® Chip showed better sensitivity for detecting M. hominis (97.0% vs. 54.5%) and U. urealyticum (93.2% vs. 65.9%). In precision tests, coefficients of variations for signal intensities were ranged from 11.2% to 26.2%. CONCLUSION: The STDetect® Chip showed excellent analytical performance, and its result was in good agreement with that obtained by direct sequencing.

Comparison between bottom-up and top-down approaches in the estimation of measurement uncertainty.

BACKGROUND: Measurement uncertainty is a metrological concept to quantify the variability of measurement results. There are two approaches to estimate measurement uncertainty. In this study, we sought to provide practical and detailed examples of the two approaches and compare the bottom-up and top-down approaches to estimating measurement uncertainty. METHODS: We estimated measurement uncertainty of the concentration of glucose according to CLSI EP29-A guideline. Two different approaches were used. First, we performed a bottom-up approach. We identified the sources of uncertainty and made an uncertainty budget and assessed the measurement functions. We determined the uncertainties of each element and combined them. Second, we performed a top-down approach using internal quality control (IQC) data for 6 months. Then, we estimated and corrected systematic bias using certified reference material of glucose (NIST SRM 965b). RESULTS: The expanded uncertainties at the low glucose concentration (5.57 mmol/L) by the bottom-up approach and top-down approaches were ±0.18 mmol/L and ±0.17 mmol/L, respectively (all k=2). Those at the high glucose concentration (12.77 mmol/L) by the bottom-up and top-down approaches were ±0.34 mmol/L and ±0.36 mmol/L, respectively (all k=2). CONCLUSIONS: We presented practical and detailed examples for estimating measurement uncertainty by the two approaches. The uncertainties by the bottom-up approach were quite similar to those by the top-down approach. Thus, we demonstrated that the two approaches were approximately equivalent and interchangeable and concluded that clinical laboratories could determine measurement uncertainty by the simpler top-down approach.

Evaluation of the Analytical Performance of the Olympus AU5421 Applied with Parameters Developed by the Toshiba 200FR for Measurement of Blood Ethanol Concentration.

BACKGROUND: An accurate determination of blood ethanol concentrations is important. To minimize ethanol degradation in blood samples, sodium fluoride (NaF) collection tubes have been recommended for use. In this study, we attempted to utilize the Olympus AU5421 chemistry analyzer for ethanol analysis based on the parameters established for the Toshiba 200FR. We also evaluated the effect of NaF collection tubes on ethanol concentrations. METHODS: The precision, linearity, accuracy, and carry-over rate of the AU5421 analyzer were evaluated. The results of analysis using the AU5421 and Abbott AxSYM analyzers were also compared. The effects of NaF collection tubes on ethanol concentrations in stored samples were measured. RESULTS: The AU5421 showed a good precision, linearity, accuracy, and carry-over rate. The ethanol concentrations were well correlated with the results obtained using the AxSYM. There was no statistically significant difference in blood ethanol concentrations between the samples collected in tubes with NaF and those collected in tubes without NaF. CONCLUSIONS: Since the AU5421 showed excellent analytical performance, the AU5421 could be used as an alternative to AxSYM for the determination of blood ethanol concentrations. Our analysis also indicated that there is no need to use NaF collection tubes if blood ethanol concentrations are analyzed within 3 h after blood collection. We believe that the results obtained in this study will have important implications for the use of the AU5421 system to measure blood ethanol concentrations.

Dual matrilineal geographic distribution of Korean type 2 diabetes mellitus-associated -11,377 G adiponectin allele.

The present study was performed to identify the susceptible single nucleotide polymorphisms (SNPs) for the prediction of Korean type 2 diabetes mellitus (T2DM) and to clarify the matrilineal origin of Korean T2DM­specific SNPs. Fourteen SNPs from the adiponectin (ADIPOQ), hepatocyte nuclear factor 4α, phosphoenolpyruvate carboxykinase 1 and glucokinase genes in the Korean population were analyzed. Only one SNP, ­11,377 C/G on the ADIPOQ gene, was finally determined to be responsible for the incidence of Korean T2DM (P=0.028). The G­T­T­A haplotype at positions ­11,377, +45, +276 and +349 on the ADIPOQ gene was also associated with a high incidence of Korean T2DM (P=0.023). In addition, the susceptibility of Korean individuals to T2DM appears to be affected by their matrilineal origin. Of note, the group of Southern origin, consisting of mitochondrial DNA macrohaplogroups F and R, was predisposed to T2DM, whereas the group of Northern origin, consisting of haplogroups A and Y, was resistant to T2DM. This implied that the differential genetics between the two groups, which were formed from the initial peopling of the proto­Korean population via Southern and Northern routes to the present time, may explain their differing susceptibility to T2DM. In conclusion, from Southern Asia Northward, a matrilineal origin of Korean individuals appears to be responsible for the prevalence of Korean T2DM caused by the ­11,377 G allele.

Usefulness of presepsin (sCD14 subtype) measurements as a new marker for the diagnosis and prediction of disease severity of sepsis in the Korean population.

PURPOSE: Presepsin has recently emerged as a new useful sepsis marker, and our study is focused on the usefulness of presepsin as earlier detection and monitoring biomarker for sepsis comparing with other conventional biomarkers. MATERIALS AND METHODS: We compared the mean values of presepsin, procalcitonin, interleukin 6, and high-sensitivity C-reactive protein levels between infection group and noninfection group of study subjects and assessed whether the values decreased during treatment. Furthemore, we evaluated the diagnostic accuracy of presepsin in sepsis and compared the mean level of presepsin to the Acute Physiology and Chronic Health Evaluation III score and mortality rate on the 30th day. RESULTS: Mean presepsin levels were significantly different between infection group and noninfection group (1403.47 pg/mL vs 239.00 pg/mL). During treatment, mean levels of presepsin decreased significantly, and in the receiver operating characteristic curve analysis, the area under curve value of presepsin was significantly higher than that of other biomarkers. The presepsin levels did not correlate significantly with Acute Physiology and Chronic Health Evaluation III scores and mortality rates on the 30th day. CONCLUSIONS: Presepsin showed significantly higher values in infection group than in noninfection group. The diagnostic accuracy of presepsin was higher than other conventional biomarkers. For early diagnosis and treatment of bacterial sepsis, presepsin could be a more useful marker than the other markers.

A real-time PCR-based amelogenin Y allele dropout assessment model in gender typing of degraded DNA samples.

Allelic dropout due to stochastic variation in degraded small quantity DNA appears to be one of the most serious genotyping errors. Most methods require PCR replication to address this problem. The small amounts of valuable samples are often a limitation for such replications. We report a real-time PCR-based amelogonin Y (AMELY) allele dropout estimation model in an AMEL-based gender typing. We examined 915 replicates of AMELY-positive modern male DNA with varying amounts of DNA and humic acid. A male-specific AMEL fragment (AMELy) dropped out in 143 genuine male replicates, leading to gender typing errors. By graphing a scatter plot of the crossing point versus the end cycle fluorescence of the male replicates, a standard graph model for the estimation of the AMELy allele dropout was constructed with the dropout-prone and dropout-free zones. This model was then applied to ancient DNA (aDNA) samples. Nine samples identified as female were found in the dropout-prone zone; with higher DNA concentrations, six were shifted to the dropout-free zone. Among them, two female identifications were converted to male. All the aDNA gender was confirmed by sex-determination region Y marker amplification. Our data suggest that this model could be a basic approach for securing AMELy allele dropout-safe data from the stochastic variation of degraded inhibitory DNA samples.

A long-term outcome of therapeutic angiogenesis by transplantation of peripheral blood stem cells in critical limb ischemia after interventional revascularization.

A 61-year-old male patient with atherosclerotic critical limb ischemia in the left leg underwent stent insertion into the left superficial femoral artery. Stenting procedures improved Rutherford grade from III-5 to II-4. Granulocyte colony-stimulating factor stimulated the production of white blood cells over four-fold and mononuclear cells (MNCs) 1.5-fold in the whole blood. Transplantation of 7.9x10(9) autologous MNCs into the left femoral artery rapidly decreased the leg pain intensity, with further improvement of Rutherford grades from II-4 to 0-0 without any side effects. In the four-year follow-up, significant improvement was found in terms of ankle brachial index, from nondetectable to 0.67, and peak systolic velocity, from 14.8 to 36.1 cm/s. Limb salvage and decreased resting pain were the notable outcomes of the treatment.

Selective death of cancer cells by preferential induction of reactive oxygen species in response to (-)-epigallocatechin-3-gallate.

(-)-Epigallocatechin-3-gallate (EGCG) induces apoptosis in cancer cells without adversely affecting normal cells. Understanding the cancer-specific cytotoxic activity of EGCG is very important in defining the mechanism of tumorigenesis and identifying superb chemotherapeutic agents against cancer. We comparatively assayed human telomerase reverse transcriptase (hTERT)-mediated apoptosis by EGCG-induced reactive oxygen species (ROS) in normal cells and cancer cells. EGCG showed differential levels of ROS induction between the cell types; ROS, especially hydrogen peroxide, was highly induced in cancer cells, while it was not in normal cells. In addition, the higher level of ROS down-regulated hTERT via binding of CCCTC binding factor (CTCF) to the core promoter region of hTERT, which repressed hTERT expression. CTCF binding was epigenetically controlled by the demethylation of the previously hypermethylated site for CTCF, which was induced by down-regulation of DNA methyltransferase 1 (DNMT1). In contrast, hTERT down-regulation was not observed in normal cells. These results suggest that preferential death of cancer cells by EGCG could be caused by the cancer-specific induction of ROS and epigenetic modulation of expression of apoptosis-related genes, such as hTERT.

Development of candidate reference reagent for HIV-1 RNA and comparison analysis for different HIV-1 RNA quantitative assay.

BACKGROUND: Human immunodeficiency virus type-1 (HIV-1) RNA viral load is a surrogate marker that is routinely used to determine indications for, and monitor the effectiveness of HIV-1 treatment. We developed three reagents for potential use in routine quality control of HIV-1 RNA quantitative assays. In this report, we compare the stability of these re-agents in storage and compare their performance in three different HIV-1 RNA quantitative assays. METHODS: The candidate reagents were derived from readily available pre-existing reagents and examined for stability at different storage temperatures. They were compared in three commercially available HIV-1 RNA quantitative assays: the Cobas TaqMan HIV-1 Test (Cobas TaqMan), the RealTime HIV-1 Assay (Abbott RealTime), and the NucliSens EasyQ HIV-1 Assay v1.1 (NucliSens EasyQ). RESULTS: The candidate reagent derived from an HIV culture supernatant (candidate CS) was the most stable of the three candidates and showed good reproducibility. Candidate CS yielded the highest HIV-1 titer of the three candidates in the Cobas TaqMan assay and the lowest HIV-1 titer and stability of the three candidates in the NucliSens EasyQ system. CONCLUSIONS: The candidate CS is the most appropriate of the three candidate reagents for quantitative testing of HIV-1 RNA. This working reagent should be useful for use in routine calibration for quality control in centers with limited financial resources. The Cobas TaqMan assay tended to yield higher viral load results than the other assays when used with our three candidate reagents.

Reduction of natural killer and natural killer T cells is not protective in cisplatin-induced acute renal failure in mice.

AIMS: A recent report showed that fractalkine (CX3CL1), which functions as both a potent chemoattractant and adhesion molecule for monocytes and natural killer (NK) cells was significantly increased in cisplatin-induced acute renal failure (CisARF) in mice. Therefore, we developed the hypothesis that increased CX3CL1 expression in CisARF initiates NK cell infiltration in the kidney. The aim of the present study was to determine the role of NK cells in CisARF in mice. METHODS: Time course of pan-NK positive cells in CisARF was investigated by using immunohistochemistry (IHC) for CD49b. Pan-NK positive cells were reduced by using anti-NK1.1 mAb. The model of pan-NK positive cells reduction was confirmed by flow cytometry of the spleen and IHC of the kidney. The expression of granzyme A and caspase-1 was examined, and the activity of caspase-1 was also determined. We performed a study on whether there was significant protection of renal function after reduction of pan-NK positive cells. RESULTS: (i) Infiltration of pan-NK positive cells was prominent on day 3 after cisplatin administration. (ii) granzyme A expression was significantly increased in CisARF and CisARF+NK1.1 Ab compared to vehicle. (iii) Caspase-1 expression and activity was significantly increased in CisARF mice compared to vehicle and CisARF+NK1.1 Ab. (iv) Reduction of pan-NK positive cells was not protective in cisplatin-induced acute renal failure in mice. CONCLUSIONS: Although infiltration of pan-NK cells was significantly increased in CisARF, reduction of infiltration of pan-NK cells into the kidney was not protective against CisARF in mice.

Clinical observation study of massive blood transfusion in a tertiary care hospital in Korea.

PURPOSE: Massive blood transfusios are uncommon. The goal of this study was to propose an ideal ratio for the blood component of massive hemorrhage treatment after review of five years of massive transfusion practice, in order to have the best possible clinical outcomes. MATERIALS AND METHODS: We defined a 'massive transfusion' as receiving 10 or more units of red blood cells in one day. A list of patients receiving a massive transfusion from 2004 to 2008 was generated using the electronic medical records. For each case, we calculated the ratio of blood components and examined its relationship to their survival. RESULTS: Three hundred thirty four patients underwent massive transfusion during the five years of the study. The overall seven-day hospital mortality for massive transfusion patients was 26.1%. Factors independently predictive of survival were a fresh-frozen plasma (FFP)/packed red blood cell (pRBC) ratio ≥ 1.1 with an odds ratio (OR) of 1.96 (1.03-3.70), and elective admission with an OR of 2.6 (1.52-4.40). The receiver operation characteristic (ROC) curve suggest that a 1 : 1 : 1 ratio of pRBCs to FFP to platelets is the best ratio for survival. CONCLUSION: Fixing blood-component ratios during active hemorrhage shows improved outcomes. Thus, the hospital blood bank and physician hypothesized that a fixed blood component ratio would help to reduce mortality and decrease utilization of the overall blood component.