A Case Study of Active Aging through Lifelong Learning: Psychosocial Interpretation of Older Adult Participation in Evening Schools in Korea

Lifelong learning is a key element of the conceptual framework of active aging. To understand how older adults experience active aging through participation in lifelong learning, the authors conducted a qualitative case study. The research participants were older adult learners attending evening schools aiming to pass the equivalency examination. Data were collected primarily using semi-structured interviews with five older adult learners, and additional data were collected from relevant documents. Data analysis and thematic discussion provided insights into how older adults experience active aging by participating in lifelong learning. Data analysis identified themes of overcoming limited education, taking the equivalency examination, and evolving goals. Thematic discussion revealed that older adults began learning to meet deficiency needs; however, they developed their goals after attending evening schools and passing the equivalency examination. In addition, lifelong learning is an indispensable element of active aging not only because learning is good for older adults' wellbeing, as reported in the literature, but also because older adults become more active in the systemic change of their environment and in the setting goals for their lives.

The 2016 WHO versus 2008 WHO Criteria for the Diagnosis of Chronic Myelomonocytic Leukemia

The 2016 WHO diagnostic criteria for chronic myelomonocytic leukemia (CMML) require both absolute and relative monocytosis (≥1×10⁹/L and ≥10% of white blood cell counts) in peripheral blood. Moreover, myeloproliferative neoplasm (MPN) features in bone marrow and/or MPN-associated mutations tend to support MPN with monocytosis rather than CMML. We assessed the impact of the 2016 WHO criteria on CMML diagnosis, compared with the 2008 WHO criteria, through a retrospective review of the medical records of 38 CMML patients diagnosed according to the 2008 WHO classification. Application of the 2016 WHO criteria resulted in the exclusion of three (8%) patients who did not fulfill the relative monocytosis criterion and eight (21%) patients with an MPN-associated mutation. These 11 patients formed the 2016 WHO others group; the remaining 27 formed the 2016 WHO CMML group. The significant difference in the platelet count and monocyte percentage between the two groups indicated that the 2016 WHO criteria lead to a more homogenous and improved definition of CMML compared with the 2008 WHO criteria, which may have led to over-diagnosis of CMML. More widespread use of molecular tests and more sophisticated clinical and morphological evaluations are necessary to diagnose CMML accurately.

A novel association between relaxin receptor polymorphism and hematopoietic stem cell yield after mobilization

Mobilization of hematopoietic stem cells (HSCs) from the bone marrow to the peripheral blood is a complex mechanism that involves adhesive and chemotactic interactions of HSCs as well as their bone marrow microenvironment. In addition to a number of non-genetic factors, genetic susceptibilities also contribute to the mobilization outcome. Identification of genetic factors associated with HSC yield is important to better understand the mechanism behind HSC mobilization. In the present study, we enrolled 148 Korean participants (56 healthy donors and 92 patients) undergoing HSC mobilization for allogeneic or autologous HSC transplantation. Among a total of 53 polymorphisms in 33 candidate genes, one polymorphism (rs11264422) in relaxin/insulin-like family peptide receptor 4 (RXFP4) gene was significantly associated with a higher HSC yield after mobilization in Koreans. However, in a set of 101 Europeans, no association was found between circulating CD34+ cell counts and rs11264422 genotype. Therefore, we suggest that the ethnic differences in subjects’ genetic background may be related to HSC mobilization. In conclusion, the relaxin—relaxin receptor axis may play an important role in HSC mobilization. We believe that the results of the current study could provide new insights for therapies that use relaxin and HSC populations, as well as a better understanding of HSC regulation and mobilization at the molecular level.

Identification of cell morphology parameters from automatic hematology analyzers to predict the peripheral blood CD34-positive cell count after mobilization

Optimal timing of apheresis initiation is important for maximizing the hematopoietic stem cell (HSC) yield. This study aimed to identify useful parameters from automatic hematology analyzers for predicting the peripheral blood CD34+ cell count after mobilization. We prospectively enrolled 53 healthy donors and 72 patients, and evaluated 43 cell morphology parameters from Unicel DxH800 (Beckman Coulter, USA) and Advia 2120i (Siemens Healthcare Diagnostics, USA). The correlation of each parameter with the CD34+ cell count in pre-apheresis blood samples was analyzed. The delta neutrophil index (DNI) from Advia 2120i, standard deviation of volume of neutrophils and monocytes (SD-V-NE and SD-V-MO), standard deviation of conductivity of neutrophils and monocytes (SD-C-NE and SD-C-MO), mean conductivity of neutrophils and monocytes (MN-C-NE and MN-C-MO), and standard deviation of axial light loss of neutrophils and monocytes (SD-AL2-NE and SD-AL2-MO) from DxH800 showed significant correlations with the CD34+ cell count. SD-V-NE, SD-C-NE, and SD-C-MO showed good or fair area under the curve values for the prediction of the CD34+ cell count. SD-V-NE, SD-C-NE, and SD-C-MO from DxH800 will provide rapid, useful information for the initiation of apheresis after mobilization.

Performance evaluation of Samsung LABGEO(HC10) Hematology Analyzer

CONTEXT

The Samsung LABGEO(HC10) Hematology Analyzer (LABGEO(HC10)) is a recently developed automated hematology analyzer that uses impedance technologies. The analyzer provides 18 parameters including 3-part differential at a maximum rate of 80 samples per hour.

OBJECTIVE

To evaluate the performance of the LABGEO(HC10).

DESIGN

We evaluated precision, linearity, carryover, and relationship for complete blood cell count parameters between the LABGEO(HC10) and the LH780 (Beckman Coulter Inc) in a university hospital in Korea according to the Clinical and Laboratory Standards Institute guidelines. Sample stability and differences due to the anticoagulant used (K₂EDTA versus K₃EDTA) were also evaluated.

RESULTS

The LABGEO(HC10) showed linearity over a wide range and minimal carryover (<1%) for white blood cell, hemoglobin, red blood cell, and platelet parameters. Correlation between the LABGEO(HC10) and the LH780 was good for all complete blood cell count parameters (R > 0.92) except for mean corpuscular hemoglobin concentration. The bias estimated was acceptable for all parameters investigated except for monocyte count. Most parameters were stable until 24 hours both at room temperature and at 4°C. The difference by anticoagulant type was statistically insignificant for all parameters except for a few red cell parameters.

CONCLUSIONS

The accurate results achievable and simplicity of operation make the unit recommendable for small to medium-sized laboratories.

Nodular lymphoid hyperplasia of the stomach in a patient with multiple submucosal tumors

Nodular lymphoid hyperplasia of the stomach is a rare lymphoproliferative disorder. Here, we report a 38-year-old man who presented with multiple submucosal tumors of the stomach. Histologically, the lesions were characterized by multiple discrete submucosal nodules of lymphoid cells. The infiltrates between the lymphoid follicles were composed mainly of medium-sized lymphoid cells with abundant clear cytoplasm, as well as a few large cells with vesicular nuclei. The gastric mucosa exhibited multifocal lymphoid aggregates and some of the epithelial cells were infiltrated by small lymphocytes mimicking lymphoepithelial lesions. Histopathology was consistent with mucosa-associated lymphoid tissue lymphoma. However, the infiltrating lymphoid cells were positive for CD2, CD3, CD5, and CD7. In addition, polymerase chain reaction analysis of the immunoglobulin heavy chain and T-cell receptor gene rearrangements demonstrated polyclonality. This case was diagnosed as reactive lymphoid hyperplasia of the stomach.

Current routine practice and clinico-pathological characteristics associated with acute promyelocytic leukemia in Korea

BACKGROUND

Acute promyelocytic leukemia (APL) can be life threatening, necessitating emergency therapy with prompt diagnosis by morphologic findings, immunophenotyping, cytogenetic analysis, or molecular studies. This study aimed to assess the current routine practices in APL and the clinico-pathologic features of APL.

METHODS

We reviewed the medical records of 48 Korean patients (25 men, 23 women; median age, 51 (20-80) years) diagnosed with APL in 5 university hospitals between March 2007 and February 2012.

RESULTS

The WBC count at diagnosis and platelet count varied from 0.4 to 81.0 (median 2.0)×10(9)/L and 2.7 to 124.0 (median 54.5)×10(9)/L, respectively. The median values for prothrombin time and activated partial thromboplastin time were 14.7 (11.3-44.1) s and 29 (24-62) s, respectively. All but 2 patients (96%) showed a fibrin/fibrinogen degradation product value of >20 µg/mL. The D-dimer median value was 5,000 (686-55,630) ng/mL. The t(15;17)(q22;q12 and PML-RARA fusion was found in all patients by chromosome analysis and/or multiplex reverse transcriptase-polymerase chain reaction (RT-PCR), with turnaround times of 8 (2-19) d and 7 (2-13) d, respectively. All patients received induction chemotherapy: all-trans retinoic acid (ATRA) alone (N=11, 26%), ATRA+idarubicin (N=25, 58%), ATRA+cytarabine (N=3, 7%), ATRA+idarubicin+cytarabine (N=4, 9%).

CONCLUSION

Since APL is a medical emergency and an accurate diagnosis is a prerequisite for prompt treatment, laboratory support to implement faster diagnostic tools to confirm the presence of PML-RARA is required.

Hemophagocytosis by leukemic blasts in B lymphoblastic leukemia with t(12;21)(p13;q22); TEL-AML1 (ETV6-RUNX1): a case report

Blasts showing hemophagocytosis have been very rarely reported in acute lymphoblastic leukemia. We report a pediatric case of B lymphoblastic leukemia (BLL) with t(12;21)(p13;q22); TEL-AML1 (ETV6-RUNX1) showing erythrophagocytosis and thrombophagocytosis by leukemic blasts. About 4% of the leukemic blasts in marrow aspirate smears showed phagocytosis of erythrocytes, platelets, or nuclear remnants in a 3-year-old Korean boy with a diagnosis of BLL. Conventional cytogenetics and molecular analysis revealed the presence of t(12;21)(p13;q22); TEL-AML1 (ETV6-RUNX1). The patient responded well to chemotherapy and is in a state of complete remission.

Acquisition of a BCR-ABL1 transcript in a patient with disease progression from MDS with fibrosis to AML with myelodysplasia-related changes

The 2008 WHO classification tentatively introduced myelodysplastic syndrome with fibrosis (MDS-F) based on previous literature of the existence of such cases. Most MDS-F cases have increased blasts, lower hemoglobin and platelet counts, an aggressive clinical course, and more frequently include cytogenetic aberrations. We report the case of a 66-year-old male patient diagnosed with refractory anemia with excess blasts-2 with fibrosis (MDS RAEB-2-F) with a normal karyotype and negative findings for both BCR-ABL1 transcript and JAK2 V617F mutations. He refused therapy upon his diagnosis and, after 5 months, his disease progressed to leukemia. The patient was diagnosed with acute myeloid leukemia with myelodysplasia-related changes (AML-MRC), based on a bone marrow exam revealing increased blasts (32.8%). Cytogenetic study revealed a complex karyotype, and molecular studies identified a minor BCRABL1 fusion transcript. The patient's general condition deteriorated despite the initiation of induction chemotherapy, and he died approximately 2 weeks after the diagnosis of AML-MRC. This patient's poor clinical outcome may have been exacerbated by the acquisition of the BCR-ABL1 fusion transcript overlapping with the aggressive nature of MDS-F.

[Current status and proposal of a guideline for manual slide review of automated complete blood cell count and white blood cell differential]

BACKGROUND

Manual slide review (MSR) is usually triggered by the results of automated hematology analyzers, but each laboratory has different criteria for MSR. This study was carried out to investigate the current status of MSR criteria of automated complete blood cell count (CBC) and white blood cell (WBC) differential results and to propose a basic guideline for MSR.

METHODS

Total 111 laboratories were surveyed regarding MSR using questionnaires. The questionnaire asked: kinds of automated hematology analyzers used and the presence of criteria triggering MSR in seven categories: 1) CBC results, 2) 5 differential WBC counts, 3) 3 differential WBC counts, 4) automated reticulocyte counts, 5) delta check, 6) instrument flags (or messages), 7) clinical information (wards or diseases). Based on the survey results, we determined basic and extended criteria for MSR. With these criteria, we consulted nine hematology experts to get a consensus.

RESULTS

All 111 laboratories had their own MSR criteria. Among 111 laboratories, 98 (88.3%) used more than three criteria for MSR including CBC results and 5-part WBC differential count results and 95 (85.6%) had criteria of flags triggering MSR. For MSR criteria with numeric values, the 10th, 50th, and 90th percentiles of upper and lower threshold values were obtained. The basic guideline for MSR was made.

CONCLUSIONS

We proposed a basic guideline for MSR. This guideline would be helpful to hematology laboratories for their daily operation and providing more rapid and accurate CBC and WBC differential results.

Usefulness of delta value of platelet parameters on ADVIA 120 for the functional reactivity of stored platelets

An agonist-induced expression of CD62P by flow cytometry analysis for evaluating platelet functional reactivity has some disadvantages. We investigated the usefulness of platelet parameters by ADVIA 120 to predict an agonist-induced expression of CD62P in stored platelets. The CD62P expression by flow cytometry and the platelet parameters by ADVIA 120 were studied in samples from 27 platelet pheresis products. Delta (Delta) values were calculated as the degree of change of the platelet parameters studied with or without adenosine 5'-diphosphate sodium (ADP) stimulation. The CD62P expression of the ADP-activated platelets were correlated with the Delta platelet count (r=0.517) in the short-term storage group (within 10 hr from preparation), with the platelet component distribution width (PCDW) without ADP (r=-0.744) and the DeltaPCDW (r=-0.755) in the long-term storage group (after 10 hr from preparation). Therefore, the delta values of platelet parameters on ADVIA 120 analysis in platelets between with and without ADP stimulation could be useful as a simple predictor for the functional reactivity of stored platelets.

Acute myeloid leukemia with t(16;21)(q24;q22) and eosinophilia: case report and review of the literature

The t(16;21)(q24;q22), a rare chromosomal translocation involving chromosome 21 in de novo and therapy-related acute myeloid leukemia (AML), produces a RUNX1-CBFA2T3 fusion gene (previously AML1-MTG16) fusion gene. The translocation has been reported in 20 patients with AML, with eosinophilia present in 3 cases. Here we report a pediatric case of t(16;21)(q24;q22) in de novo AML with eosinophilia and suggest that eosinophilia is a hematologic characteristic of at least a subpopulation of AML with t(16;21)(q24;q22). A 4-year-old Korean girl was admitted with complaints of pale appearance and dizziness, and was diagnosed with acute myelomonocytic leukemia. On admission, laboratory evaluation revealed hemoglobin at 3.3 g/dL, platelets at 9.0 x 10(9)/L, and white blood cells at 9.1 x 10(9)/L with 10% eosinophils and 1% blasts. The bone marrow aspirate contained 31% blasts and 11% eosinophils. Flow cytometric analysis revealed the expression of CD13, CD14, CD19, CD33, CD34, and HLA-DR by the leukemic blasts. The karyotype was 47,XX, + 8,t(16;21)(q24;q22)[18]/46,XX[2]. Interphase fluorescence in situ hybridization analysis with a dual-color, dual-fusion translocation LSI AML1/ETO probe set for RUNX1 and RUNX1T1 produced three signals for each probe in 90% of interphases, but no fusion signals. We confirmed the presence of RUNX1-CBFA2T3 fusion transcripts with reverse transcriptase-polymerase chain reaction, using primers AML1ex5f1 and MTG16r2.

Change of platelet activation markers using flow cytometry in patients with hematology/oncology disorders after transfusion

In spite of the frequent need of platelet transfusions, there is limited information on the association of platelet activation markers, in transfused patients with hematology/oncology disorders, with platelet function using flow cytometry. The goal of this study was to evaluate the changes of PAC-1 binding and CD62P expression, with or without agonists in patients after transfusions. Twenty-eight whole blood samples were obtained from 24 patients admitted to the department of Hematology & Oncology and transfused with platelets; these samples were compared to 30 healthy controls. Whole blood samples, either with or without agonists, such as 20 microM adenosine diphosphate (ADP) or 100 microM thrombin receptor activating peptide (TRAP), were stained with the fluorescein conjugated monoclonal antibodies PAC-1 or CD62P. Then, the percent expression for each marker was analysed using flow cytometry. ADP and TRAP induced an increased percentage of CD62P expression and PAC-1 binding after platelet transfusions compared to the samples studied before transfusion, and these findings were lower than those of the healthy controls. However, the expression of platelets without the agonists was not significantly changed, despite the transfusions. Therefore, agonist-induced platelet activation markers, studied by flow cytometry, appear to be more useful for the evaluation of platelet function after transfusions than platelet activation markers without agonists.

Genetic rearrangements of TN1546-like elements in vancomycin-resistant Enterococcus faecium isolates collected from hospitalized patients over a seven-year period

The heterogeneity of Tn1546 results from point mutations, deletions, and the integration of insertion sequence (IS) elements. Among these variations, the presence of IS elements accounts for much of the heterogeneity. Such a rearrangement could play a key role in the evolution of the vanA gene cluster, and hence, it may modify its transferability. In this study, we characterized the consequence of Tn1546 in vanA-containing Enterococcus faecium isolates collected from patients over time. From 1998 to 2004, 57 vanA-containing E. faecium isolates were collected from hospitalized patients at Ajou University Hospital in Korea. PCR amplification of internal regions of Tn1546 was performed, and both DNA strands were directly sequenced by the dideoxy termination method. All isolates were divided into three main types, including the prototype, according to the distribution of IS elements integrated into Tn1546 elements. Type I was characterized by an IS1542 insertion in the orf2-vanR intergenic region and an IS1216V insertion in the vanX-vanY intergenic region. Type II was represented by the presence of two copies of IS1216V at the 3' end of IS1542 and in the vanX-vanY intergenic region, as well as IS1542 in the orf2-vanR intergenic region. Seventeen strains isolated from 1998 to 2000 represented type I, and 38 strains isolated from 2000 to 2004 represented type II. The remaining two isolates were the prototype. The tendency for the rearrangement of Tn1546 was that the sequences were shortened as time passed, especially at the left or the right end, and hence, this could gradually modulate their transferability.

Effects of Confluent, Roscovitine Treatment and Serum Starvation on the Cell-cycle Synchronization of Bovine Foetal Fibroblasts

The present study was designed to examine the effects of cell-cycle synchronization protocols, such as confluent, roscovitine treatment and serum starvation, in bovine foetal fibroblasts on synchronization accuracy at G0/G1, viability, apoptosis, necrosis and ploidy for use as a nuclei donor. The cells in 5-10 passages were randomly allocated into three treated groups. Cells were cultured either in Dulbecco's modified Eagle's medium (DMEM) + 10% foetal bovine serum (FBS) until 90% confluent (group 1, confluent), in DMEM + 10% FBS + 30 microM roscovitine for 12 h (group 2, roscovitine), or in DMEM + 0.5% FBS for 5 days (group 3, serum starvation). Most of the cells (>80%) in all groups were arrested at the G0/G1 stage. Although the rates did not differ, cells in group 1 showed an increased cell population arrested at the G0/G1 phase. Significantly (p < 0.05) higher rates of apoptosis occurred in group 3 than in group 1 and 2 (10% vs 6% and 6%, respectively). No differences in chromosomal abnormality were observed among groups. However, by increasing the number of cell culture passages up to 15, significantly (p < 0.05) higher chromosomal abnormality was observed than in 5 and 10 passages (39% vs 28% and 23%, respectively) in group 1. The results clearly indicated that bovine foetal fibroblasts could be effectively synchronized at G0/G1 stages by all the three different treatments, confluent, roscovitine and serum starvation. However, cells in confluent showed reduced apoptosis and necrosis when they underwent 5-10 passages, exhibiting increased percentage of cells with stable chromosome diversity. Hence, cells in confluent merit further studies before they could be used as nuclear donors.

Reduction in glycopeptide resistance in vancomycin-resistant enterococci as a result of vanA cluster rearrangements

The molecular characterization of five clinical isolates of vanA-containing vancomycin-resistant enterococci with altered resistance to glycopeptides was examined. One strain represented an IS1216V insertion accompanied by partial deletion of the reading frame of vanX following a transposition event. The other four strains represented IS1216V within the vanX-vanY intergenic region associated with deletion of vanY or vanZ.

A chronic heart failure model by coronary artery ligation in the goat

The availability of a reliable heart failure model in large animals is important. We report upon our efforts to develop a chronic heart failure model in seven goats using sequential ligation of the left anterior descending (LAD) coronary artery and its diagonal branch. After anesthesia and left thoracotomy, the LAD artery was ligated, and the diagonal vessel at the same level was ligated one hour later. Cardiac measurements were performed with a thermodilution catheter and by ultrasonography. Two months after the operation, the same measurements were made and animals were sacrificed for postmortem examinations of their hearts. Hemodynamic measurements, except cardiac output, showed no significant changes immediately after the coronary artery ligation. Echocardiographic measurements showed significant changes in the ejection fraction and fractional shortening without changes in left ventricular dimensions. Wall motion analyses demonstrated variable degrees of anteroseptal dyskinesia and akinesia in all animals immediately after coronary artery ligation. Five animals have undergone hemodynamic and ultrasonographic studies 2 months after coronary artery ligation. The results obtained from these animals showed significant increases in central venous pressure, right ventricular pressure, pulmonary artery pressure, and pulmonary artery capillary wedge pressure, and a significant decrease in cardiac output. Increases in left ventricular dimensions and decreases in ejection fraction with fractional shortening in ultrasonographic studies were also observed. Pathologically, well-demarcated thin-walled anteroseptal infarcts, with chamber enlargement, were clearly seen with dilatation of the heart chambers in all specimens. Based on this study, we conclude that goats, like sheep, can provide a reliable model of chronic heart failure by coronary artery ligation and in view of the many advantages offered by goats, we believe that this animal model will be useful for cardiac experimentation.

A study of blood usage by diagnoses in a Korean university hospital

BACKGROUND AND OBJECTIVES

There is paucity of comprehensive data on the blood usage with regard to diagnostic categories of Asian recipients. The purpose of this study is to analyse data for blood usage in a korean university hospital in order to obtain additional information on transfusion practices in relation to diagnoses.

MATERIALS AND METHODS

Data of information on patients discharged during the period from March 1996 to February 2002, who have received packed red blood cells (RBC), fresh frozen plasmas (FFP), and platelet components (PLT) were extracted from the computerized registers. We used only the principal four-digit diagnostic categories of the Tenth Revision of International Classification of Diseases.

RESULTS

A total of 397 489 units of blood components (RBC 171 916 units; FFP 69 301 units; and PLT 156 272 units) were transfused for 17.2% of all discharged patients. Acute myeloid leukaemia, liver cell carcinoma, advanced gastric cancer, alcoholic or other unspecified cirrhosis of liver were the top 5 diagnoses related with the highest usage of blood component.

CONCLUSIONS

The results showed a different blood usage pattern compared to those of previous studies. These provide a baseline transfusion practice at our institution, and the data would help in predicting future blood needs in a variety of diagnostic categories.

Erythrophagocytosis by myeloid cells in a patient with myeloproliferative disorder

This report documents a case of myeloid erythrophagocytosis in a patient with myeloproliferative disorder. The patient had pancytopenia and his marrow was hyperplastic with erythrophagocytosis by myeloid cells of various stages, including myeloblasts. He was diagnosed to have a prefibrotic stage of chronic idiopathic myelofibrosis. The erythrophagocytosis by myeloid cells persisted even after 2 months of treatment for the primary disorder.

Localization of cytoskeletal proteins in Pneumocystis carinii by immuno-electron microscopy

Pneumocystis carinii causes serious pulmonary infection in immunosuppressed patients. This study was undertaken to observe the cytoskeletal proteins of P. carinii by immuno-electron microscopy. P. carinii infection was experimentally induced by immunosuppression of Sprague-Dawley rats for seven weeks, and their lungs were used for the observations of this study. The gold particles localized actin, tropomyosin, and tubulin. The actin was irregularly scattered in the cytoplasm of the trophic forms but was much more concentrated in the inner space of the cell wall of the cystic forms called the inner electron-lucent layer. No significant amount of tropomyosin was observed in either trophic forms or cystic forms. The tubulin was distributed along the peripheral cytoplasm and filopodia of both the trophic and cystic forms rather than in the inner side of the cytoplasm. Particularly, in the cystic forms, the amount of tubulin was increased and located mainly in the inner electron-lucent layer of the cell wall where the actin was concentrated as well. The results of this study showed that the cell wall of P. carinii cystic forms is a structure whose inner side is rich in actin and tubulin. The location of the actin and tubulin in P. carinii suggests that the main role of these proteins is an involvement in the protection of cystic forms from the outside environment by maintaining rigidity of the cystic forms.

Purification of a 68-kDa cysteine proteinase from crude extract of Pneumocystis carinii

The present study intended to verify activities of cysteine proteinase of Pneumocystis carinii from rats and to purify the enzyme. In order to exclude the contamination of host-derived enzymes, concentrates of P. carinii was primarily treated with a mixture of proteinase inhibitors before lysis of P. carinii. A 68-kDa cysteine proteinase was finally purified from the crude extract of P. carinii by 4 sequential chromatographic methods. The enzyme showed an optimal activity at pH 5.5 in 0.1 M sodium acetate, and its activity was specifically inhibited by L-trans-epoxy-succinylleucylamido (4-guanidino) butane (E-64) and iodoacetic acid, suggesting that the enzyme is a cysteine proteinase. The 68-kDa proteinase weakly digested macromolecules such as collagen, hemoglobin and fibronectin. The present study demonstrated the activity of cysteine proteinase at the 68-kDa band of P. carinii, and purified and characterized the molecule.

Genetic heterogeneity of Pneumocystis carinii from rats of several regions and strains

Pneumocystis carinii is a major opportunistic pathogen which has been found in the lungs of a wide variety of mammalian host species, and the fact suggests the possibility of intraspecific variation. Until now, P. carinii from different mammalian species are differentiated as subspecies, and the rats are known to be infected by two subspecies. The present study investigated genetic heterogeneity of P. carinii isolates from two strains of rats in Korea and China by molecular karyotyping, RFLP and sequencing analysis. Karyotypes of P. carinii were grouped into three, two from two strains of rats in Korea and one from rats in China. However RFLP of PCR product of ribosomal and MSG gene of the P. carinii isolates showed same pattern. The sequence homology rates of alpha-tubulin DNA of the P. carinii isolates were 96% in Seoul Wistar rats, 93% in Seoul Sprague-Dawley rats, and 85% in Chinese Sprague-Dawley rats. The present finding confirmed that P. carinii from rats in Korea are grouped into two karyotype strains which are different from that of P. carinii from rats in China. The Chinese isolate shows a little different sequences of alpha-tubulin DNA.

Usefulness of IgG4 subclass antibodies for diagnosis of human clonorchiasis

The present study analyzed serum IgG subclass antibody reaction to major antigenic bands of Clonorchis sinensis to investigate improvement of its serodiagnosis. Of the four subclass antibodies, IgG1 and IgG2 antibodies were produced but not specific, IgG3 antibody was least produced, and IgG4 antibody was prominent and specific. The serum IgG antibody reaction to any of 43-50, 34-37, 26-28, and 8 kDa bands was found in 65.5% of 168 egg positive cases while IgG4 antibody reaction was found in 22.0% of them. The positive rates of IgG and IgG4 antibodies were directly correlated with the intensity of infection. All of the sera from heavily infected cases over EPG 5,000 showed positive reaction for specific IgG and IgG4 antibodies. The specific serum IgG4 antibody disappeared within 6 months after treatment. The bands of 35 kDa and 67 kDa cross-reacted with IgG antibodies but not with IgG4 antibodies in sera of other trematode infections. The present findings suggest that serum IgG4 antibody reaction to 8 kDa band is specific but not sensitive. Any method to increase its sensitivity is required for improved serodiagnosis.

Karyotypes of Pneumocystis carinii derived from several mammals

Pneumocystis carinii is the most important opportunistic pathogen of humans in the world. Pneumocystis carinii is experimentally detected in the lungs of rats, mice, rabbits, and monkeys, however, the organisms from different mammals are identical in microscopic morphology. The present study tried to find out more mammalian hosts of P. carinii and also to differentiate the organisms from different mammals by karyotyping. Rats, mice, hamsters, rabbits, cats, and dogs were successfully infected by P. carinii, but guinea pigs and pigs were not. Karyotype of P. carinii from rabbits showed similar size range of chromosomes with that of the prototype, but in different pattern. The patterns from cats and dogs were also different from that of rats. The present study confirms that cats and dogs are infected by P. carinii and at least total three karyotype strains of P. carinii are proven in Korea.

Clinical and molecular biological analysis of a nosocomial outbreak of vancomycin-resistant enterococci in a neonatal intensive care unit

Vancomycin-resistant enterococci (VRE) have emerged as important nosocomial pathogens since 1988. We report here an outbreak of VRE between April 1997 and May 1997 in our neonatal intensive care unit (NICU). All isolates from four patients were identified as Enterococcus faecium positive and were resistant to vancomycin and teicoplanin. All of the patients with VRE were isolated for at least 5 d after admission to the unit and the positive cultures lasted between 13 and 31 d. There were no cases of sepsis or mortality in the patients with VRE. Two cases had previously received vancomycin therapy. All isolates were shown to have the vanA gene and had the same band pattern on repetitive PCR. After the four episodes, all equipment used to care for the patients were decontaminated and the staff engaged in therapy used disposable gloves and gowns. There were no more episodes. However, the NICU is no longer a safety area with regards to vancomycin-resistant enterococcal infection.

The effect of heterogeneous hyperimmune IgG antibody on prophylaxis and treatment of Pneumocystis carinii infection in rats

Immunotherapy has been used in support of trimethoprim-sulfamethoxazole treatment for Pneumocystis carinii pneumonia. The present study investigated the therapeutic or preventive effects of heterogeneous hyperimmune IgG antibody (HIA) in experimental rats. Their immunity was suppressed by steroid injection, and they were also injected peritoneally with HIA which reacted with 40-55, 92, 116, and 200 kDa bands of the crude antigen. All rats were infected by P. carinii and the cystic forms on lung impression smears were counted. The count was 20.5-76.5 (mean 52.5 + 19.3) in those which received steroid only, but decreased to 6.0-21.0 (mean 13.5 + 10.6) in those of group 3 which received HIA for the same duration. In other groups, the mean count ranged from 29.9 + 32.9 to 54.1 + 47.7, and in those which received 13.7 mg HIA the reduction effect was greater than in those which received 6.8 mg or 20.5 mg HIA. The present finding confirmed that in rats during the early stage of infection, the heterogeneous HIA to MSG antigen bands had a partial effect on P. carinii pneumonia, both prophylactically and therapeutically.

Short-course doxycycline treatment versus conventional tetracycline therapy for scrub typhus: a multicenter randomized trial

To assess the clinical efficacy of short-course doxycycline in the treatment of scrub typhus, we compared conventional 7-day tetracycline therapy with 3-day doxycycline therapy in 116 patients. Patients were randomized to receive either tetracycline (500 mg four times daily; n = 50) or doxycycline (100 mg twice daily; n = 66) and were followed for 4 weeks after the completion of treatment. The cure rate was 100% in the tetracycline group and 93.9% in the doxycycline group (P > .05). The two groups did not differ significantly in terms of the interval required for defervescence or for the alleviation of symptoms. There were no relapses in either group. These data suggest that 3-day doxycycline therapy is as effective as conventional 7-day tetracycline therapy for the cure of scrub typhus and the prevention of relapses.

[Infection status of the sea eel (Astroconger myriaster) purchased from the Noryangjin fish market with anisakid larvae]

Although the sea eel (Astroconger myriaster) is suspected as one of the most important fish host for human anisakiasis in Korea, no report has been made on the infection status of the sea eel with anisakid larvae. In the present study, 26 sea eels (Astroconger myriaster) were purchased from the Noryangjin fish market in Seoul, and anisakid larvae were collected from their viscera, muscle, head and skin. The collected larvae were classified by their morphological types. A total of 1,351 anisakid larvae were collected from 15 of 26 fish examined. Among them, 1,269 were recovered from the viscera, 66 from the muscle, and 16 from the head and skin. Morphologically, most of the anisakids were classified into 6 known larval types, Anisakis type I (564 larvae) of Berland (1961), Contracaecum type A (409) and type D (5) of Koyama et al. (1969), Contracaecum type C' (83) and type D' (117) of Chai et al. (1986), and Contracaecum type V (1) of Yamaguti (1935). Remaining 172 specimens were new in the available literature, hence, designated as Contracaecum type A' (new type). The present results revealed that the sea eels caught in the Korean waters are heavily infected with anisakid larvae, not only in their viscera but also in the muscle, and Anisakis type I was the most common among the 7 larval types.

Percutaneous retrieval of a broken Lunderquist guidewire from the pelvicalyceal system

The stiff Lunderquist guidewire may occasionally be needed during percutaneous insertion of a nephrostomy catheter, especially in patients with a large amount of subcutaneous fat or with a hard renal capsule. This wire may fracture at the junction of its stiff portion with the flexible tip. We have reported such an occurrence, in which an operative procedure was avoided by successful percutaneous retrieval of the broken wire tip, using the loop-snare technique.

Treatment of biliary obstruction caused by metastatic cancer

Over an 8-year period, among 41 patients with obstructive jaundice caused by metastases to the liver or lymph nodes adjacent to the porta hepatis, palliative biliary decompression was established surgically in 11, by percutaneous transhepatic biliary drainage (PTBD) in 25, and by both methods in 2. Three patients had no drainage procedure performed. Early mortality after drainage occurred in 6 of 38 patients, and the median survivals (actuarial) for the remaining 32 patients were 4.5 months for the surgical group (range 2 to 21 months) and 4 months for the PTBD group (range 2 to 14 months). Although there were trends toward more frequent hospital readmissions and episodes of cholangitis in the PTBD group, the only statistically significant difference was in the number of catheter manipulations required. We concluded that when patients develop obstructive jaundice as a manifestation of metastatic cancer, useful palliation can be achieved by either surgical or percutaneous decompression.

Treatment of peripheral arterial obstruction with streptokinase: results in arterial vs graft occlusions

A retrospective study of the efficacy of local low-dose intraarterial streptokinase for the treatment of peripheral arterial occlusion was performed in 60 cases. The results of treatment of occlusion of native arterial and arterial graft occlusions were compared. Twenty-two (73%) of 30 cases of arterial occlusion showed complete or partial angiographic resolution, compared with 16 (53%) of 30 cases of arterial graft occlusion. Ten (71%) of 14 patients with venous arterial grafts were successfully treated vs only six (38%) of 16 patients with prosthetic arterial grafts. These results suggest that streptokinase is an effective fibrinolytic agent for the treatment of arterial occlusion and arterial graft occlusion. Its effectiveness in arterial graft obstruction is comparatively low, although patients with venous grafts respond much more favorably than those with synthetic conduits.