Keunsik Park

Platelet recovery after eradication of Helicobacter pylori in patients with idiopathic thrombocytopenic purpura

Abstract. The association between Helicobacter pylori (H. pylori) infection and idiopathic thrombocytopenic purpura (ITP) has been reported by several groups. We investigated the prevalence of H. pylori infection and the effectiveness of its eradication in Japanese patients with ITP. H. pylori infection was found in 21 of 30 patients (70.0%) by 13C urea breath test and presence of serum antibodies to H. pylori. H. pylori was eradicated in 18 of the 21 infected patients (85.7%) by administration of a proton pump inhibitor and two kinds of antibiotics. In only one patient was medication discontinued due to skin rash on the 4th day of treatment. Platelet recovery was obtained in ten patients (55.6%). In two patients with treatment failure, platelet recovery was obtained after successful re-eradication. In three patients without H. pylori infection, platelet counts did not significantly increase with the same treatment. On the other hand, eradication therapy did not affect platelet counts in patients with gastric ulcer. In conclusion, H. pylori eradication can be used for initial treatment with tolerable adverse effects in some ITP patients.

An Enzymatic Assay for Erythrocyte Creatine as an Index of the Erythrocyte Life Time

OBJECTIVES To establish and estimate an enzymatic measurement of creatine in erythrocytes as an index of the erythrocyte life time. DESIGN AND METHOD The measurement of creatine in erythrocytes was performed using an enzymatic assay kit that was developed for serum and urine creatine. An erythrocyte sample was subjected to creatine measurement after hemolysis and deproteinization. Performance of the method for creatine measurement in erythrocytes was estimated. Effects of age and gender on the creatine content of erythrocytes were also estimated in 305 normal subjects. RESULTS The method showed within-run CVs varying from 0.7 to 1.0% (n = 20), and between-day CVs from 1.3 to 1.7% (15 days). Good linearity was observed at least up to 1000 mumol/L as creatine value in hemolyzed sample. The analytical recovery was calculated to be 98.1 +/- 1.3% on average. No considerable interference by various substances, including guanidino compounds and amino acids, with the assay was observed. Excellent correlation was observed between the present method and high performance liquid chromatography. With the unit of mumol/g Hb: slope, 1.034 +/- 0.003 (mean +/- SD); intercept, -0.059 +/- 0.012 (mean +/- SD); correlation coefficient, 0.9996; and Sy.x, 0.069. With the unit of mumol/L RBC: slope, 1.033 +/- 0.003 (mean +/- SD); intercept, -18.23 +/- 3.55 (mean +/- SD); correlation coefficient 0.9996; and Sy.x, 20.40. A significant increase in erythrocyte creatine was observed in females aged 11- to 50 years old as compared with males in the corresponding age bracket, however, a gender difference was not observed in other age bracket. This finding suggests the possibility of a slight decrease in the erythrocyte life time due to menstruation in females. CONCLUSION This study showed that the present method is favorable for quantifying erythrocyte creatine, and has analytical characteristics suitable for routine work in clinical laboratories.

Detection of various platelet-associated immunoglobulins by flow cytometry in idiopathic thrombocytopenic purpura

In 1975, Dixson reported that anti‐platelet IgG on platelets from patients with idiopathic thrombocytopenic purpura (ITP) is greater than in normal people, by determining anti‐platelet antibodies directly on the platelet surface with a quantitative complement lysis–inhibition–assay. Since then, platelet‐associated IgG (PAIgG) has been thought of as evidence of ITP. Although platelets from ITP patients show significantly higher PAIgG values than from normal control individuals, PAIgG is not specific for autoantibody because it increases in other than immune ITP patients.

Effectiveness of weekly polymerase chain reaction-based open reading frame typing analysis of all newly isolated methicillin-resistant Staphylococcus aureus strains for controlling nosocomial infections

Polymerase chain reaction (PCR)-based open reading frame typing (POT) helps differentiate between bacterial strains based on the open reading frames (ORFs) of the prophage-encoding genes; multiplex PCR screening is performed to identify strains based on keeping patterns. At our hospital, surveillance of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) transmission is undertaken using POT to conduct molecular epidemiological analysis for all newly detected MRSA strains. In 2014, we performed POT only once a month; however, in 2015, we increased the frequency of POT to once a week, which helped us detect nosocomial transmission that would normally be difficult to detect, and thus achieve 40% reduction in nosocomial transmission, compared to that in 2014. This suggests that weekly POT screening for all MRSA strains is one of the effective methods available for minimizing nosocomial transmission of MRSA.

Interleukin-6 may play an important role in thrombopoiesis: a case of leukemic transformation from myelodysplastic syndrome

We describe an interesting case of the elevation of platelet level parallel with the increase of blast cells that produce interleukin-6 (IL-6). The patient is a 56year-old man with overt leukemia transformed from myelodysplastic syndrome (MDS). On admission, hematological findings were: hemoglobin 4.5 g/dl, leukocytes 43,100/ml (73.0% leukemic cells), platelets 52!10/ml. The bone marrow aspiration sample revealed a nucleated cell count of 230!10/ml (57.2% leukemic cells) and a megakaryocyte count of 250/ml. The bone marrow blood smear demonstrated dysplastic features of erythroblasts, granulocytes, and megakaryocytes. The leukemic cells were positive for myeloid antigens (CD33). Chromosomal analysis showed a normal male karyotype. The clinical course of the patient is illustrated in Fig. 1. Cytosine arabinoside (Ara-C 60 mg, every 12 h) was administered subcutaneously for 5 days. At the recovery from nadir status after chemotherapy, the platelet count increased parallel with the increase of leukemic cells, reaching 378!10/ml. No significant change in bone marrow (50.4% leukemic cells) was observed after chemotherapy. High levels of IL-6 in the peripheral blood (11.1 pg/ml) and bone marrow plasma (39.3 pg/ml) were observed on the 30th hospital day. To clarify the possibility that leukemic cells produce IL-6, the IL-6 concentration of the culture supernatant of leukemic cells from the bone marrow was measured.

The Use of Electronic Medical Record Data to Analyze the Association Between Atrial Fibrillation and Birth Month

Objectives Cardiovascular disease is a condition of enormous public health concern. Recently, a population study newly revealed associations between cardiovascular diseases and birth month. Here, we investigated the association between atrial fibrillation in cardiovascular disease and birth month. Methods We retrospectively extracted birth date data from 6,016 patients with atrial fibrillation (3,876 males; 2,140 females) from our electronic medical records. The number of live births in Japan fluctuates seasonally. Therefore, we corrected the number of patients for each birth month based on a Japanese population survey report. Then, a test of the significance of the association between atrial fibrillation and birth month was performed using a chi-square test. In addition, we compared the results of an analysis of patient data with that of simulated data that showed no association with birth month. Results The deviations of birth month were not significant (overall: p = 0.631, males: p = 0.842, females: p = 0.333). The number of female patients born in the first quarter of the year was slightly higher than those born in the other quarters of the year (p = 0.030). However, by comparing the magnitudes of dispersion in the simulated data, it seems that this finding was mere coincidence. Conclusion An association between atrial fibrillation and birth month could not be confirmed in our Japanese study. However, this might be due to differences in ethnicity. Further epidemiologic studies on this topic may result in reduction of disease risk in the general population and contribute to public health.

Measuring Attitudes Toward Nursing Safety Violations.

This study measured implicit and explicit attitudes toward major nursing safety violations using the Implicit Association Test (IAT) and self-reported questionnaires, respectively. Experiment 1 sampled nursing students (n = 71), and Experiment 2 sampled patient safety nurses (n = 38). Although reaction time to IAT stimuli of major nursing safety violations was quicker than of general nursing behaviors, error trials did not reveal a significant difference between IAT stimuli of major nursing safety violations and of general nursing behaviors in Experiment 1. Explicit attitude was related with intention to violate safety protocols in Experiment 1. In Experiment 2, both reaction time and error trials showed significant differences between IAT stimuli of major nursing safety violations and of general nursing behaviors. This was interpreted in that patient safety nurses had formed a firm implicit attitude, unlike the nursing students; however, the findings suggested that attitudes were not related to violations in nursing.

Analysis of Human and System Factors on Errors in ICD Coding with Electronic Discharge Summary System

This study aimed at clarifying the issues of the system that needs to be improved in order to raise the precision of computer-assisted ICD-10 encoding, by analyzing the inconsistency between the codes registered by physician and encoded by experts in discharge summaries of the electronic patient record system. It was found that human related factors led to the major inconsistency at the chapter level of ICD-10. Substantial commitment of coding experts was considered practically important to correct careless mistakes in physician’s entry and assign accurate codes to complicated diagnoses, while relatively small improvement of the system was thought feasible as countermeasures against the inconsistency caused by system related factors.

Preliminary evaluation of discovered-rule-filtering methods

Data mining systems semi-automatically discover knowledge by examining large volumes of data, but the knowledge so discovered is not always novel to users. We introduce a discovered-rule-filtering approach that uses information retrieval results from the Internet to assess rules discovered by data mining and find those that are novel to the user. To implement this approach, we create 2 methods: the micro view method and the macro view method. In the micro view method, we extract keywords from a discovered rule and rank the rule referring to the number of hits returned when the keywords are submitted to an appropriate database. In the macro view method, we first retrieve documents by submitting every pair of extracted keywords and then form keyword clusters according to the results. We evaluated the methods by sending out a questionnaire to medical students and using the MEDLINE database as our Internet source. The evaluation indicates that the macro view method is promising.

Interleukin-2 induces motility of human lymphocytes, but not their mobility

Interleukin-2 induces cytotoxic and antitumor activities of human lymphocytes. For the expression of these activities, the cytoskeletal system is probably activated. This study was do;ne to find if interleukin-2 causes cell movement. Lymphocytes were incubated with interleukin-2, and their morphology and motile activities were studied. After 72 hr of incubation, some 29% of lymphocytes were larger than before; nucleoli had formed and the microvilli were well-developed. The membrane potential of the lymphocytes increased during incubation. Motility under agar after 3 days of incubation with interleukin-2 was examined. Cells aggregated in clumps in the incubation well, and migration was not observed. When mobility was examined with Boydens method, fewer cells incubated with interleukin-2 migrated than in control preparations. Cells incubated with interleukin-2 were extracted with Triton X-100. The extract obtained had three more bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis than the controls. The band were at the positions for the molecular weights of 270,000-300,000. We concluded that interleukin-2 activated the motility of lymphocytes, but not their mobility.