Exposure Assessment of Airborne Bacteria and Fungi in the Aircraft

Objective@#The exposure levels of disease-causing bacteria and germs were assessed on aircraft cleaning workers on multiple different aircrafts.MethodFive measuring points were selected depending on the aircraft types. Four aircraft cleaning agencies were selected for the test. Aircraft cleaning work was classified as intensive cleaning and general cleaning work. Ventilation in aircraft when sampling during the cleaning operation was categorized into forced ventilation and natural ventilation. The collection of airborne microorganisms was made through inertial impactors which were installed 1.5 meters above the bottom of the aircraft. The airborne bacteria and fungus growth badges were selected by Trytpic Soy Agar and Sabouraud Dextrose Agar. @*Results@#The average concentrations of bacteria in the air were higher in the order of small, medium, and large airplanes. Rainy days had higher concentrations inside and outside the aircraft as compared to those in sunny days. Regarding ventilation, concentrations in natural ventilation were higher than concentrations in forced ventilation. According to the type of work, the concentrations in the intensive cleaning groups (cleaning one plane a day) were lower than those of the ordinary cleaning groups (cleaning several planes per day). @*Conclusion@#The concentration levels of airborne bacteria and fungi in the aircraft surveyed were lower than the indoor environmental standards of Korea (800 cfu/m3 and 500 cfu/m3). The average concentrations of bacteria in the air and fungi in the air were highest in small aircraft owned by Company D.

The Discrimination Power and Effectiveness of 3 Kinds of LTR Primers in the VNTR-PCR for Evaluation of the Engraftment of Allogeneic Peripheral Blood Stem Cells Transplantation / 대한임상병리학회지

BACKGROUND: There are highly-polymorphic DNA markers in the human genomic DNA, known as the variable number of tandem repeats (VNTR). The VNTR markers can be used to evaluate the engraftment of stem cells. We evaluated the discrimination power of 3 types of long-tandem repeat (LTR) and tried to predict underlying disease relapses by DNA chimerism. METHODS: Twenty-nine patients were transplanted with allogeneic peripheral blood stem cells (PBSCs) and their related donors were tested. We used the three long-tandem repeats (LTR) D1S80, D1S111, and YNZ22 for VNTR-PCR. The informative test was performed before transplantation. The chimerism analysis was performed on days +30, +60, +90, and +180 after transplantation. RESULTS: The most informative marker was D1S80 with 55.2% discrimination potential. The power of discrimination was 79.3% in the combination of 3 LTRs. Twenty-two cases were tested for DNA chimerism analysis. When the complete chimerism was represented, the engraftment was more successful and when the mixed chimerism was represented, the underlying disease relapse rate increased. CONCLUSTIONS: DNA chimerism analysis was useful to evaluate the marrow status of patients. It also served as an indication for donor lymphocyte infusion. However, compared to unrelated allogenic PBSCT, the discrimination potential for the combination of 3 LTR loci was lower in the related allogenic PBSCT. Therefore, it is thought that additional short-tandem repeats and DNA sequencing are required for more discrimination power especially in related transplantation cases.

Allogeneic Peripheral Blood Stem Cell Transplantation with Stepwise Donor Lymphocyte Infusions in Mantle Cell Lymphoma Relapsed after Autologous PBSCT / 대한혈액학회지

Mantle cell lymphoma (MCL) is a distinctive clinicopathologic entity and represents 5~10% of all non-Hodgkin's Lymphoma (NHL). The median survival of patients with MCL is only 3 years, and none of the available conventional chemotherapy regimens appear curative. Encouraging results have been reported with high dose chemotherapy with stem cell transplantation for its treatment. Particularly, alloSCT appears to induce durable remission via graft-versus-lymphoma (GVL) effect. Donor lymphocyte infusions (DLIs), by virtue of graft-versus-tumor effect, have been shown to induce remissions in leukemia that recurs after alloSCT. But GVL effect of DLI has not been clearly established in NHL. We describe a patient with relapsed MCL shortly after high dose chemotherapy with autoSCT who was successfully treated with alloPBSCT. The patient presented with diffuse GI and spleeninvolvement at the time of alloPBSCT. The patient received Bu/Cy/VP-16 as preparative regimen followed by alloPBSCT. The patient received cyclosporin and methotrexate as GVHD prophylaxis. Prednisone was added after grade II GVHD. The patient had partial response by D+64. To enhance GVL effect, the patient received G-CSF primed DLI serially at D+64 and D+92. Grade IV GVHD developed 19 days after 2nd DLI and was partially controlled with a combination of cyclosporin, prednisone and mycophenolate mofetil. Clinical complete remission was observed at D+112, and maintained till last follow-up day (D+515). Our findings suggest that alloSCT and stepwise DLIs may offer a curative approach to MCL.

THE EFFECT OF CYCLIC LOADING ON THE RETENTIVE STRENGTH OF FULL VENEER CROWNS / 대한치과보철학회지

Dislodgement of a crown or extension bridge and the loosening of a retainer of a bridge is a serious clinical problem in fixed restoration. Generally these problems are considered to be associated with deformation of the restoration. During biting, the restoration is subjected to complex forces and deforms considerably within the limit of its elasticity. Deformation of the restoration under the occlusal force induces excessive stress in the cement film, which then leads to the cement fracture. Such a fracture may eventually cause loss of the restoration. Because most of the past retention tests for full veneer crown were done without fatigue loading, they were not exactly simulating intraoral environment. And the purpose of this study was to evaluate the effect of cyclic cantilever loading on the retentive strength of full veneer crowns depending on different type of cements and taper of prepared abutment. Steel dies with 8degrees or 16degrees convergence angle were fabricated through milling and crowns with the same method. These dies and crowns were divided into 8 groups. Group 1: 16degrees taper die, cementation with zinc phosphate cement, without loading Group 2: 16'taper die, cementation with zinc phosphate cement, with loading Group 3: 8degrees taper die, cementation with zinc phosphate cement, without loading Group 4: 8degrees taper die, cementation with zinc phosphate cement, with loading Group 5: 16degrees taper die, cementation with Panavia 21, without loading Group 6: 16degrees taper die, cementation with Panavia 21, with loading Group 7: 8degrees taper die, cementation with Panavia 21, without loading Group 8: 8degrees taper die, cementation with Panavia 21, with loading After checking the fit of die and crown, the luting surface of dies and inner surface of crowns were air-abraded for 10 seconds. The crowns were cemented to the dies, with cements mixed ac cording to the manufacturer' s recommendations. A static load of 5 kg was then applied for 10 min utes with static loading device. Twenty-four hours later, group 1,3,5,7 were only thermocycled, group 2,4,6,8 were subjected to cyclic loading after thermocycling. Retentive tests were performed on the Instron machine. From, the finding of this study, the following conclusions were obtained. 1. Panavia 21 showed significantly higher retentive strength than zinc phosphate cement for all groups(p0.05). 3. Cyclic loading significantly decreased the retentive strength for all groups (p<0.05) . 4. For zinc phosphate cement, there was 35% reduction of the retentive strength after loading in the 16degrees taper die, 25% in the 8degrees taper die, and for Panavia 21, 21% in the 16degrees taper die, 18% in the 8degrees taper die.

Mantle cell lymphoma presented as multiple lymphomatous polyposis: clinical review of 4 cases / 대한내과학회지

Multiple lymphomatous polyposis(MLP) is an interesting clinical entity of non-Hodgkin's lymphoma(NHL) and is defined as B-cell lymphoma characterized by the presence of multiple lymphomatous polyps along the gastrointestinal tract. Recently MLP has been considered as a variant form of mantle cell lymphoma(MCL). The median survival of patients with MCL is only 3 years, and none of the available conventional chemotherapy regimens appears curative. Encouraging results have been reported with high dose chemotherapy with autoSCT and alloSCT for its treatment. We introduce 4 cases of MLP diagnosed as MCL by morphologic and immunologic method. The common clinical findings of these cases were splenomegaly (4/4), multiple intraabdominal lymphadenopathy (4/4), and advanced stage (3/4) at presentation. The overall remission duration was relatively short (5-27 months) and three of four cases relapsed after conventional chemotherapy or autologous stem cell transplant. Our report suggests that MCL presented as MLP is a high risk subgroup of NHL and more aggressive approach may be needed for cure.

Hepatitis G Virus Infection Rate in Blood Donors, Hemodialysis Patients and Hepatitis C Infected Patients / 대한임상병리학회지

BACKGROUND: A recently identified Flaviviridae-like agent, termed hepatitis G virus (HGV), has been recognized as a non A-E hepatitis agent, but its relation to liver disease and transmission mode are not well understood. We investigated HGV infection rate in Korea and tried to clarify its relation to the liver disease. METHODS: 145 blood donors, 39 hemodialysis patients and 22 hepatitis C virus (HCV) infected persons were investigated for the presence of HGV by nested reverse transcriptase polymerase chain reaction (nested RT-PCR) with primers from the 5' UTR of HGV and some liver function tests. In each PCR assay, one positive and two negative controls were included. RESULTS: HGV-RNA was detected in 11 (7.6%) of 145 young voluntary blood donors and in 5 (12.8%) of 39 hemodialysis patients and in 8 (36.4%) of 22 HCV infected patients. All HGV RNA positive hemodialysis patients have a past history of transfusion, but they had a remarkably shorter duration of hemodialysis than those of HGV-negative patients. HCV infected patients with HGV-RNA tended to be younger than those without HGV-RNA. In all 15 HGV-RNA infected individuals without hepatitis B and C infection, alanine amino transferase was not increased except in 2 cases. Liver function tests did not show a significant difference between HGV-RNA positive patients and negative patients. CONCLUSIONS: Hepatitis G virus infection rate was much higher in Korea than other countries, so we suggested that group life could be another transmission mode other than blood transfusion. But even in infected cases, HGV did not seem to cause hepatitis and a high proportion cleared the virus after a relatively short time.

Expression Patterns of Immunologic Surface Markers in Acute Leukemia / 대한혈액학회지

BACKGROUND: Immunophenotyping is an important technique for the diagnosis and classification of acute leukemia, as well as French-American-British (FAB) classification on the basis of morphologic characteristics and cytochemistry. We evaluated the expression patterns of immunologic surface markers in acute leukemia. METHODS: Peripheral or bone marrow leukemic cells from 75 leukemic patients (acute lymphoblastic leukemia, ALL 40 cases; children (26 cases), adults (14 cases) and acute myeloid leukemia, AML 35 cases; children (9 cases), adults (26 cases)) were studied. Monoclonal antibodies which were designed for two color direct immunofluorescence (IF) analysis with combination of fluoresceinisothiocynate (FITC) and phycoerythrin (PE) conjugated, CD10/CD19, CD20/CD5, CD3/CD22, CD7/CD33, HLA-DR/CD13 (Acute Leukemia Phenotyping Kit, Becton Dickinson; BD, USA) were analyzed by flow cytometry. RESULTS: Blasts from these patients could be classified as CALLA (+)B-ALL (26 cases, 65.0%), CALLA (-)B-ALL (6 cases, 15.0%), T-ALL (6 cases, 15.0%), biphenotypic ALL (2 cases, 5.0%). The positive expression rates were CD19 (100%), CD10 (78.1%), CD22 (75.0%) and CD20 (50.0%) in B-ALL, CD7 (100%), CD3 (50.0%) and CD5 (50.0%) in T-ALL and CD33 (85.7%), CD13 (74.3%) in AML, respectively. The incidence of acute mixed lineage leukemia (AMLL) was 26.7% and leukocytosis, anemia and thrombocytopenia were frequently seen in AMLL. CONCLUSION: By the study of immunophenotyping we could more exactly diagnosed ALL and AML, as well as AMLL which was not exactly diagnosed by characteristics of morphology and cytochemistry only. Therefore the best method for the diagnosis of acute leukemia will be achieved by using of immunophenotyping and FAB classification on the basis of morphology and cytochemistry.

A Case of Hemorrhagic Colitis Complicated by Hemolytic Uremic Syndrome / 감염

We report a case of hemolytic uremic syndrome (HUS) associated with hemorrhagic colitis. A 35-year-old man was admitted to a local hospital because of abdominal pain and watery diarrhea that had developed about 6 hours after taking roast beef. He was treated with intravenous fluids and antibiotics, but watery diarrhea changed to bloody in nature from the next day. He was transferred to our hospital due to progressive ascites and jaundice on his 8th day of illness. Examinations revealed ascites, jaundice, microangiopathic hemolytic anemia, thrombocytopenia and uremia. Sorbitol-negative Escherichia coli was isolated from his stool, which proved as Shiga-like toxin-negative E. coli, serotype O25. His conditions improved markedly after three times of plasmapheresis and intravenous fluid therapy, and the organism was not isolated from the follow-up stool culture.

Characterization of Heparin:PF4 Isoantibody Interaction to Platelets in Heparin-Induced Thrombocytopenia/ Thrombosis / 대한임상병리학회지

BACKGROUND: Heparin-induced thrombocytopenia/ thrombosis (HITT) is recognized as the most frequent and fatal symptom complexes in patients receiving heparin therapy. The antibodies of HITT are not directly bound to heparin but bound to complexes of heparin and platelet factor 4 (PF4) derived from platelet alpha-granules. That is, HITT IgG antibody-heparin-PF4 immune complexes are bound to FcgammaRII receptor of platelets, which induced thrombocytopenia. Some researches showed the antibodies reactive to platelets could be IgM or IgA as well as IgG. So in this study, the authors tried to explain the molecular basis of heparin-PF4-isoantibody complexes . METHODS: In HITT patients who had received long-term heparin therapy, we determined HITT isoantibodies and titers using heparin:PF4 ELISA. When fifteen HITT patients with high titer antibodies (more than 1 : 100) were selected, reaction patterns of isoantibodies with the platelets were examined through serotonin release test and flow cytometry. RESULTS: All patients showed one or more isotype antibodies and the most frequent isotype was IgGl (nine patients) . In the presence of optimal concentra pion of heparin and PF4, ten patients had antibodies which activated platelets, and all of them were positive in serotonin release test. Reactive plasmas had IgGl, IgG3, IgA or IgM antibodies, and each of them except one had IgGl. These platelet activations could be blocked in vitro by anti-IV.3 antibody. Non-reactive plasmas were negative In serotonin release assay nor had TgGl. The plasmas 4hat had two or more isoantibodies showed a similar pattern of the IgG antibody by flow cytometry. CONCLUSIONS: The HITT antibodies can be all kinds of antibody isotopes, but IgA and IgM may not bind to the platelets directly. It seems to be possible only after reacting with heparin-PF4-IgG complexes.