Rinsho byori. The Japanese journal of clinical pathology最新文献

In Japan, the criteria for multi-drug-resistant Acinetobacter baumannii (MDRA) have been developed in response to two large-scale MDRA outbreaks reported in 2010. A. baumannii can survive for a long period in a dry environment, and it is also detected frequently from carriers over a long period. For mixed infection with some other bacteria, it cannot be accurately detected due to masking by other bacteria. For these reasons, the detection of MDRP infection is delayed. Furthermore, the infection control of MDRA must require the determination of the quarantine period, release criteria, and a clean environment, without sufficient levels of evidence. It is not rare for this to take more than a year to resolve an MDRA outbreak. Therefore, it is important to monitor daily occurrence in any hospital. [Review].

It is well known that the antigenicity of unstained sections put on a slide glass decreases when the slides are stored at room temperature. Several methods have been reported to prevent reduced antigenicity, such as storing in a dark place at 4°C, covering sections with paraffin or a sheet, and storing in a deep freezer at -80°C. The aim of the present study is to determine how long unstained sections can be stored in a refriger- ator (ie, 1 week, 2 weeks, 1 month and 2 months). Each section was well stained and equal to the day 0 section for CD3, CD20, bcl-2, bcl-6, ER, PgR, HER2, Ki-67, chromogranin-A, synaptophysin, CK5, CK7, CK20, and TTF-1. In conclusion, unstained sections can be used for immunostaining after at least 2 months of storage, and preparing several control sections and storing them in a refrigerator is useful for minimizing control block loss. [Original].

Paraproteinemia is a condition induced by an increase in paraprotein. Paraprotein is a monoclonal immu- noglobulin produced by plasma cells as a result of aging or malignancy. Paraprotein often induces a variety of laboratory test abnormalities by interfering with laboratory test reagents. The haptoglobin (Hp) measurement in a 55-year-old woman with IgM-lambda type paraproteinemia associated with lymphoplasmacytic lymphoma was found to be falsely low because of white-turbidity caused by an abnormal reaction. An in- creased absorbance was observed at 596 nm after the addition of the buffer reagent and was reduced by dilution with saline. This result indicates the existence of interfering substances in the patient's sample. To identify the inhibitors, we obtained the white-turbidity pellet by centrifugation of a mixture of the patient's serum and the Hp buffer reagent. A high IgM concentration was observed in the white-turbidity pellet. Moreover, a correlation was observed in a time series between the IgM concentration in sera and the extent of the turbidity during the Hp measurement. These results indicated that IgM was the main component of the white-turbidity. Next, we showed that the addition of the white-turbidity pellet to normal serum caused an increase in absorbance and a false low Hp value. A correlation was also observed in a time series be- tween the IgM concentration in sera and the rate of the Hp reduction. These results suggest that the false low Hp measurements were due to IgM present in the white-turbidity. In conclusion, false low values of Hp may occur in patients with IgM-lambda type paraproteinemia. Therefore, the presence or absence of an increase in absorbance after the addition of the buffer reagent in a time-course reaction may be required.

Vancomycin-resistant enterococci (VRE) have been detected from all over Japan since 1996. However, the incidence has been relatively low. In 2006, we organized Kyoto VRE surveillance group, established a VRE control program, and conducted an investigation which was to control the post-outbreak prevalence of VRE in the affected Kyoto region. The study period was from 2005 to 2010. Faecal samples were subjected to VRE screening, and vancomycin resistance genes were detected by polymerase chain reaction (PCR). A VRE control program consists of a laboratory-based faecal VRE screening system, annual surveillance of hospital inpatients and the promotion of adequate infection control measures. Number of VRE-detected patients was significantly smaller in hospitals with routine laboratory-based faecal VRE screening. From an- nual surveillance, the rate of faecal VRE carriage among the patients enrolled in the annual surveillance in- creased until 2007, when it reached 24(1.2%) of the 2,035 enrolled patients. The rate began to decrease in 2008 and, by 2010, reached a low of 4(0.17%) of the 2,408 enrolled patients. While VRE did spread within the Kyoto region, our program succeeded in controlling the overall VRE spread. [Review].

MRSA has been a major pathogen associated with nosocomial outbreaks. Moreover, the isolation of community-acquired MRSA(CA-MRSA) is increasing even in Japanese hospitals. It is necessary to carry out outbreak investigations in cooperation with the clinical laboratory as it is the site where MRSA is identi- fied. "Timing of information on MRSA from the clinical laboratory" is crucial for the ICT. To detect signs of an outbreak, information on the number of MRSA isolates is essential in every ward per week or month. It is desirable to perform active surveillance routinely. However, there are problems to be solved such as the cost of active surveillance, workload of laboratory technicians, and shortage of private rooms for isolation. It is necessary that the infection control department confirms clonal spread on analysis of the molecular epi- demiology, including the PCR-based open reading frame typing (POT) method. When the number of MRSA isolates increased and some strains had the same POT number on a ward, we suspected MRSA outbreak and strengthened infection control measures. We describe herein the importance of the relationship with the clinical laboratory for infection control and how to control an MRSA outbreak rapidly. [Review].

Medical research that has utilized the residual parts of clinical samples after routine laboratory examination has yielded numerous findings and contributed to the progress in clinical medicine as well as the detailed elucidation of pathological states of various diseases. However, ethics guidelines on human medical research have recently been established by the Japanese Government, and the Personal Information Protection Law has now imposed stricter rules. Therefore, the enactment of a new guideline became necessary for the secondary utilization of the residual parts of clinical samples. Basic concepts are proposed as follows: (1) research utilizing the residual parts of clinical samples can be performed using an opt-out form that guarantees the right to refuse'8eing enrolled in a study; and (2) the importance and significance of such studies using residual samples should be disseminated in society. To support the promotion of laboratory medical research and avoid the unnecessary or excessive suppres- sion of research, the Japanese Society of Laboratory Medicine is aiming to devise and disseminate appropriate ethics guidelines. [Review].

Mitochondrial respiratory chain complexes are responsible for the oxidative phosphorylation system, and the association of these complexes is called a supercomplex. Since the formation of supercomplexes en- hances energy production and reduces electron leakage, the destabilization of supercomplexes may increase oxidative stress and mitochondrial dysfunction in the presence of aging and neurodegenerative disease. Both blue native polyacrylamide gel electrophoresis (BN-PAGE) and high-resolution clear native (hrCN) - PAGE are effective to examine supercomplex formation. Since the sensitivity of the in-gel enzyme activity assay of hrCN-PAGE is higher than that of BN-PAGE, we used hrCN-PAGE and two-dimensional hrCN/ SDS-PAGE to examine supercomplex formation in human mononuclear leukocytes, and compared them in relation to the sex and age group. We also applied the results to the analysis of soluble oligomer formation in neurodegenerative disease. Herein, we introduce the possibility of applying a clinical laboratory test for neurodegenerative diseases. [Review].

Routine laboratory tests are performed in almost all hospitals in the world. If you can fully interpret such routine laboratory tests, you can evaluate the general condition of patients in detail. In the reversed clinico- pathological conference (RCPC), we analyzed a patient's condition using only data from routine laboratory tests, as one of the most effective training methods to acquire the ability to interpret routine laboratory tests. In this RCPC, we discussed routine laboratory data from a patient who was transported by ambulance due to systemic weakness, and conducted interpretation of the data using the method of Shinshu University Hospital. At Shinshu University Hospital, we consider the time series results of the routine laboratory tests according to 13 steps, because our aim is to understand the patient's condition without oversight rather than to make a diagnosis. [Review].

Protein induced by vitamin K absence or antagonist-II (PIVKA-II) is an abnormal prothrombin lacking gamma-carboxylation of the 10 glutamic-acid residues in the N-terminal region. PIVKA-II has been used as an effective biomarker of hepatocellular carcinoma (HCC) since the PIVKA-II level is not correlated with that of alpha-fetoprotein (AFP), which is another effective biomarker for HCC. Monoclonal antibodies for the clinical biomarker test are usually expensive because of their high production costs. Recently, many studies involving the expression of the recombinant globulin molecules in bacterial cells and plants have been con- ducted. These studies have enabled us to produce recombinant monoclonal antibodies at much lower costs. In this study, we first produced a hybridoma expressing a monoclonal antibody against PIVKA-II, and then we constructed and produced a single-chain fragment-variable antibody (scFv), created by the linking of variable regions of light- and heavy-chains of the PIVKA-II monoclonal antibody with a peptide linker of triplicated GGGGS. The scFv was expressed in E. coli and exhibited high specificity for PIVYKA-II binding, while its binding titer was low. [Review].

Routine laboratory tests are the most frequently performed among clinical laboratory tests, and they can provide important information for the diagnosis and treatment of patients. They are more useful when sev- eral data are combined to interpret the pathophysiological state of a patient. Changes of routine laboratory data are important even when they are within their reference ranges, and they sometimes show a more de- tailed condition of the patient. In this RCPC, we-focused on changes of albumin and electrolytes, bacterial infections, and anemia. [Review].