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Background: Insulin measurement is used for the diagnosis of hypoglycemia and for insulin pharmacokinetic evaluations. We assessed the analytical and clinical performance of the ARCHITECT® insulin assay, a chemiluminescent immunoassay recently introduced for the ARCHITECT i2000 fully automated immunoassay analyzer (Abbott Laboratories). We also tested whether major insulin analogs cross-reacted with the immunoassay reagents. Methods: We used Clinical and Laboratory Standards Institute protocols to assess the analytical performance of the ARCHITECT insulin assay and compared its accuracy with that of the E-test TOSOH II (IRI) from TOSOH Corporation. We used 3 recombinant insulin analogs (lispro, aspart, and glargine) to evaluate the cross-reactivity of insulin analogs with the ARCHITECT immunoassay reagent. Results: The total CV for the ARCHITECT assay was Conclusions: The ARCHITECT insulin assay showed favorable basic performance, including reproducibility, dilution linearity, detection limit, and effects of interfering substances. When interpreting results, clinicians and laboratory pathologists should be aware of the cross-reactivity of the ARCHITECT and other immunoassays to specific insulin analogs prescribed to diabetes patients.

A quantitative nested reverse transcriptase polymerase chain reaction (QN-RT-PCR) method was developed using a plasmid cDNA containing the AML1/ETO (MTG8) fusion transcript from Kasumi-1 cells, an acute-myelogenous leukemia cell line with the t(8;21) translocation. In this method, the plasmid was detectable at a concentration of 10(-17) m. The fusion transcript in a mixture of 10(7) Rice94 (Burkitt lymphoma cell line) cells containing two Kasumi-1 cells was detectable at 10(-17) m. In a previously published real-time PCR method, the plasmid containing the fusion transcript was detectable at 10(-16) m or higher, and 20 or more Kasumi-1 cells were detectable in 10(7) Rice94 cells. Thus, this QN-RT-PCR method is more sensitive than the real-time PCR. When the same samples were examined by real-time PCR and our QN-RT-PCR method, in one patient in clinical remission after chemotherapy and allogeneic-bone marrow transplantation (BMT), the transcript was detected by QN-RT-PCR 60 days prior to hematological relapse, in contrast to 10 days before hematological relapse by real-time PCR. The transcript level was below 10(-17) m (undetectable) with this QN-RT-PCR in patients in clinical remission after chemotherapy and BMT, while it was 10(-15)-10(-16) m in patients in clinical remission after chemotherapy alone. The quantitative difference of the transcript level in minimal residual disease (MRD) between these two different types of clinical remission was estimated to be at least 10(2)-fold. This QN-RT-PCR method is useful for predicting hematological relapse and for quantitatively estimating MRD in different types of clinical remission.

Background: A new enzyme immunoassay (EIA) for automated detection of antinuclear antibodies (ANAs) uses a mixture of HEp-2 cell extracts and multiple recombinant nuclear antigens immobilized on beads. We compared this EIA and an immunofluorescence (IF) assay in a large group of patients and controls. Methods: We studied 492 healthy individuals and 307 patients with connective tissue diseases (CTDs). Sera were tested by an automated EIA (COBAS® Core HEp2 ANA EIA; Roche Diagnostics) and IF. Samples were also tested for eight disease-specific antibodies, including antibodies against U1RNP, Sm, SSA/Ro, SSB/La, Scl-70, Jo-1, dsDNA, and centromere. Results: Areas under ROC curves for the EIA were greater than (P = 0.008–0.012) or numerically identical to areas for the IF method for each of six CTDs studied. ROC areas for EIA were 0.98 (95% confidence interval, 0.95–0.99), 0.99 (0.96–1.00), and 0.99 (0.98–1.00) in systemic lupus erythematosus (n = 111), systemic sclerosis (n = 39), and mixed connective tissue disease (n = 33), respectively. For all 258 CTD patients with conditions other than rheumatoid arthritis (RA), the sensitivity and specificity of the IF method at a cutoff dilution of 1:40 were 92% and 65%, respectively, vs 93% and 79% for the EIA at a cutoff of 0.6. For the IF method at a cutoff dilution of 1:160, sensitivity and specificity were 81% and 87%, respectively, vs 84% and 94%, respectively, for the EIA at a cutoff of 0.9. For 207 sera containing at least one of eight disease-specific ANAs, positivities for the EIA and the IF method were 97.1% and 97.6%, respectively, at cutoffs of 0.6 and 1:40 (P = 0.76). Conclusions: An EIA that can be performed by a fully automated instrument distinguishes CTDs (except RA) from healthy individuals with both higher sensitivity and specificity than the IF method when the cutoff index was set at 0.9. Moreover, it can be used to exclude the presence of disease-specific ANAs by setting the cutoff index at 0.6 with almost the same efficacy as the IF method.

レイノー現象の発症には末梢血中のセロトニンによる一過性の微小血栓形成が血小板-血管壁系の異常を引き起こしている可能性が注目されている.我々は微小な血小板凝集を検出可能なレーザー散乱粒子計測型血小板凝集能測定装置を用いて,レイノー現象を有する患者の血小板凝集能を検討した.まず自然凝集およびセロトニン凝集について検討を行った.次にこれらの患者についてセロトニン受容体(5-HT 2 A)拮抗剤(塩酸サルポグレラート: SPG)投与前後での血小板凝集能の変化を観察した.レイノー現象を有する患者10名と健常成人10名を対象とした. SPG投与前の患者群と健常者群の両者で自然凝集は認めず,セロトニン凝集は健常者群に比しSPG投与前の患者群で有意に低下していた.患者群のSPG投与8週間後のセロトニン凝集は投与前に比し亢進し, SPGを服用していない健常者群とほぼ同程度の凝集がみられるようになった. SPGの長期投与によって血漿セロトニン濃度が低下することが知られており,その結果血小板表面のセロトニン受容体発現の亢進を介して外来性セロトニンに対する凝集が亢進した可能性が考えられた.

ライト付きスタイレット(TRACHLIGHTTM:以下TL)は,非直視下に頸部からの透過光を目安に気管内挿管する方法で,操作法も比較的容易に習得でき,挿管困難症例に対してもその有用性が報告されている.今回われわれは過去3回の麻酔の際,喉頭鏡および気管支ファイバーで気管内挿管できなかった患者に対し,TLを使用することにより容易かつ短時間で挿管に成功した症例を経験した.TLは挿管困難症例に対して有効な手段の一つと考えられた.

Apolipoprotein B-48 (apo B-48) is a constituent of chylomicrons and chylomicron remnants, and its fasting concentration has been reported to be a marker of postprandial hyperlipidemia, which is thought to be a risk factor of atherosclerosis.We evaluated the serum apo B-48 concentrations by chemiluminescence enzyme immunoassay (CLEIA), which was recently introduced as Lumipulse f fully automated immunosaasy analyzer by Fujirebio Inc (Tokyo, Japan), and performed immunoblotting on agarose gel electrophoresis with anti-apo B-48 antibody.Apo B-48 assay was intra-assay reproducible (CVs: 1.9-3.1%) and inter-assay reproducible (CVs: 2.2-4.4%). The assay range for apo B-48 was from 0.2 to 40.0 microg/ml. The effects of interfering substances such as free/conjugated birirubin, hemoglobin, Intrafat, ascorbic acid and rheumatoid factor were negligible. For storage, it was preferable to freeze, and to avoid frozen-thaw process as much as possible. Anti-apo B-48 antibody was reactive over a wide range from origin to the position of very-low-density lipoproteins in immunoblotting after agarose gel electrophoresis.Apo B-48 measurement by CLEIA was feasible to clinical use for the assessment of lipoprotein metabolism.

Creatinine clearance (Ccr) is generally used as a halmark of glomerular filtration rate (GFR) in clinical medicine. Recently, it has been suggested that serum cystatin C measurement in serum reflects GFR. We compared serum cystatin C, serum creatinine, and serum beta2-microgrobrin in 70 patients with renal diseases in reference to creatinine clearance. The correlation between Ccr and 1/cystatin C was higher (r = 0.830) than that between Ccr and 1/serum creatinine (r = 0.789) or 1/serum beta2-microgroburin (r = 0.732). The levels of serum cystatin C in patients with Ccr ranging from 51 to 70 ml/min were significantly higher than those in patients with Ccr ranging more than 91 ml/min. Receiver-operated characteristic (ROC) analysis revealed that serum cystatin C showed the highest area under the curve among the three when Ccr = 90 ml/min was used as the cutoff point. We conclude that serum cystatin C is more useful than serum creatinine to detect early renal dysfunction.

For the effective treatment of diabetic mellitus (DM), patients are encouraged to self-manage their disease according to the doctor's instructions and advice from certified diabetes educators (CDE) and other comedical staff. Therefore, the cooperation of medical staff consisting of a doctor, CDE, nurse, pharmacist, dietitian, and medical technologist is important for DM education. Medical technologists licensed for CDE (MT-CDE) have been participating in the DM education team in Kobe University Hospital since 2000. MT-CDE are in charge of classes for medical tests, guidance for self-monitoring of blood glucose and teaching how to read the fluctuation graph of the blood glucose level in the education program for hospitalized DM patients. MT-CDEs teach at the bedside how to read the results of medical tests during the first few days of hospitalization using pamphlets for medical tests. The pamphlets are made comprehensible for patients by using graphics and photographs as much as possible. It is important to create a friendly atmosphere and answer frank questions from patients, since they often feel stress when having medical tests at the early stage of hospitalization. This process of questions and answers promotes their understanding of medical tests, and seems to reduce their anxiety about having tests. We repeatedly evaluate their level of understanding during hospitalization. By showing them the fluctuation graph of the glucose level, patients can easily understand the status of their DM. When prescriptions are written on the graph, their therapeutic effects are more comprehensible for the patients. The items written on the graph are chosen to meet the level of understanding of each patient to promote their motivation. In summary, the introduction of MT-CDE has been successful in the education program for DM patients in our hospital. We plan to utilize the skills and knowledge of MT-CDE more in our program so that our DM education program will help patients cope with life with DM.

Rheumatoid factor (RF) has been commonly used as a marker of rheumatoid arthritis (RA). RF can be detected in 60-80% of RA patients, but the specificity is low against other rheumatic diseases patients. We evaluated the diagnostic accuracy of anti-cyclic citrullinated peptide antibody (anti-CCP), a new diagnostic test for RA. Anti-CCP demonstrated higher sensitivity (81.0%) and specificity (92.4%). By the receiver operating characteristic (ROC) curve analysis, anti-CCP was superior to other markers (ie. RF, CARF, IgG-RF, and MMP-3). In early RA patients (RA patients who had had disease symptoms for2 years), sensitivity was 68.8%. Positivities of anti-CCP in RA patients became higher as the advance of stage defined by the Steinbrocker classification. We concluded that anti-CCP is a very valuable tool for the diagnosis of RA. Moreover, anti-CCP is a useful for finding RA of recent onset.

A patient consulted the emergency room with acute pancreatitis, hypertriglyceridemia, and diabetes mellitus, and was later admitted to the hospital. Serum levels of total cholesterol(TC) and total triglyceride (TTG), and the cholesterol(Chol) versus triglyceride(TG) ratio(Chol/TG) for lipoprotein fractions were examined periodically during the course of treatment using Chol/Trig Combo, which identifies Chol and TG by differential staining. On admission, the patient's TTG, pancreatic amylase and glucose levels were 4020 mg/dl, 2012 IU/l, and 242 mg/dl, respectively. Clinofibrate administration resulted in a decrease in Chol and TG values for all fractions. However, the Chol/TG ratios were unchanged(HDL of 0.2 to 0.4, VLDL of approximately 0.13, and LDL of 0.1 to 0.2: Reference values from 103 healthy students were as follows: HDL 5.8 +/- 2.0, VLDL 0.39 +/- 0.1, and LDL 4.9 +/- 1.3[Mean +/- SD].). During clinofibrate treatment, TC and TG values gradually increased. Clinofibrate was discontinued and fenofibrate administration was initiated. This was followed by a dramatic improvement in TC, TTG and Chol/TG values for both HDL and LDL. The monitoring of lipoprotein fraction values proved useful for determining the treatment regimen for this patient with hypertriglyceridemia.

Quantitative measurement of serum hepatitis C virus(HCV) RNA is important in predicting and monitoring interferon(IFN) therapy. We compared the sensitivity of HCV RNA measurement of different HCV genotypes between two available assays, Roche Monitor 1.0(v1.0) and Roche Monitor 2.0(v2.0). We also evaluated serum level of HCV RNA as the predictors of a long-term response to IFN therapy by distinguishing the complete responders(CR), partial responders(PR) and non-responders(NR) for IFN therapy. We quantified the serum HCV RNA levels in 151 patients and determined the genotypes; 96(64%) with genotype 1b(1b), 42(28%) with genotype 2a(2a), and 6(4%) was not identified. The relationship between the genotype and effects of IFN treatment was as follows: 23CR(1b:11, 2a:9), 15PR(1b:8, 2a:7), 20NR(1b:14, 2a:6). The RNA levels of 2a measured by v2.0 were significantly higher than those by v1.0(p0.05), although no significant difference was found in 1b between two assays. By using v2.0, when the cut-off level was set at 200 x 10(3) IU/ml before IFN therapy, CR was discriminated from PR, NR with a predicting efficiency of 88%. HCV RNA levels before IFN therapy were significantly lower in patients who became HCV RNA negative within 2 weeks than in patients who did at 4 weeks or longer. These results suggest that v2.0 is more sensitive and accurate than v1.0 for the quantification of 2a. Using v2.0 assay, it was shown that low viral titre at pretreatment and loss of viraemia within 2 weeks after treatment might be important markers for a long-term response to IFN therapy, irrespective of viral genotype. The v2.0 assay was found to be more useful in predicting effectiveness of IFN therapy.