Kinetic analysis of microbial desulfurization of model and light gas oils containing multiple alkyl dibenzothiophenes.

The reaction mechanism of biodesulfurization was investigated using whole cells of Rhodococcus erythropolis KA2-5-1, which have the ability to convert dibenzothiophene (DBT) into 2-hydroxybiphenyl. The desulfurization patterns of alkyl DBTs were represented by the Michaeis-Menten equation. The values of rate constants, the limiting maximal velocity (Vmax) and Michaelis constant (Km), for desulfurization of alkyl DBTs were calculated. The relative desulfurization activities of various alkyl DBTs were reduced in proportion to the total carbon numbers of alkyl substituent groups. Alkyl DBTs that had a total of six carbons of alkyl substituent groups were not desulfurized. The type or position of alkyl substituent groups had little effect on desulfurization activity. The desulfurization activity of each alkyl DBT, when mixed together, was reduced. This phenomenon was caused by apparent competitive inhibition of substrates. Using the apparent competitive inhibition model, the desulfurization pattern of a multiple components system containing alkyl DBTs was elucidated. This model was also applicable for biodesulfurization of light gas oil.

Increase in desulfurization activity of Rhodococcus erythropolis KA2-5-1 using ethanol feeding.

Rhodococcus erythropolis KA2-5-1 is one of the best strains for the desulfurization of dibenzothiophene (DBT) via a sulfur-specific pathway in which DBT is converted to the end product, 2-hydroxybiphenyl, by releasing sulfite via DBT-sulfone and 2-(2'-hydroxyphenyl) benzene sulphinate. The objective of this research is to develop a culture method in order to attain a high cell density with a high level of specific desulfurization activity. Compared with glucose or glycerol, ethanol was found to be a preferable carbon source for obtaining a high specific activity (SA) of desulfurization. When the amount of DBT fed was restricted by feeding 2.9 mg-DBT/g-ethanol solution, the maximum SA and final cell concentration were 135.5 (mmol-2HBP/kg-dry cell weight-h) and 37 (g-dry cell weight/l), respectively. On the other hand, when glucose or glycerol was used as a carbon source, the SA was lower than 50 (mM-2HBP/kg-dry cell weight-h) and the final cell concentration was also lower than 27 (g-dry cell weight/l). The activities of the desulfurization enzymes in R. erythropolis KA2-5-1 grown on ethanol were remarkably higher than when the strain was grown on glucose or glycerol. It was also suggested that NADH, which is produced by the biochemical reaction of NAD with ethanol catalyzed by alcohol dehydrogenase, might contribute to the conversion of FMN to FMNH2, which is a coenzyme for the activities of desulfurization enzymes.

[Prevention of MRSA spread in the neurological field: intranasal application of mupirocin calcium ointment].

From September 1997 to March 1998, forty patients with cerebral disorders were investigated. They were divided into two groups: one treated and the other untreated. Mupirocin calcium ointment (MCO) was applied three times a day for three days into the nasal cavities of the patients in the treated group. In order to check the growth of MRSA (methicillin-resistant Staphylococcus aureus), bacterial isolation culture from the nasal cavity was carried out on admission, one week after admission and one month after admission. MRSA was nor detected in isolation culture of any of the cases on admission. One week later MRSA was detected in isolation culture of one case of the 20 MCO treated patients and in three of the 20 untreated patients. There was no significant difference between treated and untreated groups. In isolation culture after one month, MRSA was recognized in four cases of 16 in the MCO treated group (three patients were discharged and one expired). On the other hand, it was recognized in eight cases of thirteen in the untreated group (seven cases were discharged). MRSA infection of the nasal cavity decreased significantly due to MCO treatment (p < 0.05). It is suggested that the nasal carriage of MRSA was prevented by intranasal application of MCO on admission.

Inhibitory effect of a nucleoside analog, acyclovir, on leukemia cells.

Acyclovir (ACV), a nucleoside analog, has been demonstrated previously to suppress selectively the proliferation of NIH3T3 fibroblastic cells transformed by either v-abl or bcr-abl gene transfection. From a viewpoint of clinical application of ACV, we investigated whether ACV inhibited the growth of leukemia cells expressing either p210 BCR-ABL or p185BCR-ABL. Acyclovir exerted an inhibitory effect on OM9;22 cells, p185BCR-ABL expressing cells, in a dose-dependent manner. Despite no down-modulation of a BCR-ABL tyrosine kinase activity or its expression was observed after treatment with ACV, cell cycle analysis demonstrated synchronization of OM9;22 cells at the G0/G1 phase. This suggests that, although ACV does not directly act on BCR-ABL tyrosine kinase, ACV may exert its inhibitory effect on some leukemia cell lines via alterations of the cell cycle. Although selective inhibition of Philadelphia chromosome-positive leukemia cell growth was not apparent, our data provides a therapeutic possibility for ACV in the treatment for leukemia.

[The successful use of recombinant human erythropoietin therapy to anemia of granular lymphocyte proliferative disorder].

A 54-year-old man was admitted with fatigue. The peripheral blood count showed leukocytosis (9, 600/microliters), including 76% granular lymphocytes (GLs), which expressed CD2, 3, 8, 16 and HLA-DR, and anemia (hemoglobin 8.1 g/dl). He was diagnosed as having T cell type-granular lymphocyte proliferative disorder with anemia. Bone marrow examination revealed the involvement of 4.6% of GL and erythroblastopenia. A clonogenic assay of bone marrow cells revealed the decrease in erythroid colony formation in both CFU-E and BFU-E, but the number of erythroid colonies increased when CD8-positive cells were depleted from bone marrow cells and the number of erythroid colonies decreased again when CD8-positive GLs were added. The supernatant of cultured CD8-positive GLs had no inhibitory effect on CFU-E and BFU-E colony formation. These suggested that CD8-positive GLs suppressed the erythroid colony formation in this case. Treatment with 6,000 U/body of recombinant human erythropoietin (rh-Epo) subcutaneously three times a week was started and increased dose of 12,000 U/body of rh-Epo led to an increase in the hemoglobin level to 10.5 g/dl two months later. He has been treated with rh-Epo only.

[The enzymatic character of myeloma cell].

Thymidine kinase (TK) is a cellular enzyme required for the incorporation of thymidine into DNA. It catalyses the conversion of deoxythymidine to deoxythymidine monophosphate (dTMP). The synthesis of dTMP from deoxythymidine is called the salvage pathway. There are two types of thymidine kinase, distinguished by there biochemical and physico-chemical characteristics. Cytosolar TK is found in dividing cells in stages G1-S. Mitochondrial TK is found in mitochondria. Serum thymidine kinase (S-TK) levels can be determined by the use of a radioenzyme assay method. These are increased in proliferating cells (S phase). It is a useful tool for the clinical evaluation, staging, and follow-up of patients with multiple myeloma.

[Clinical course of a HIV-seropositive patient with thrombocytopenia and hypergammaglobulinemia who was initially screened by annual complete physical examination].

A 57-year-old man was admitted because of hypergammaglobulinemia which was initially pointed out by annual complete physical examination. No significant abnormal findings were observed except polyclonal hypergammaglobulinemia at that time (IgG; 2,662 mg/dl, IgA; 422 mg/dl). Seven months later, he has progressed to show thrombocytopenia. The laboratory data showing the reduction of peripheral CD 4-positive T cells (CD 4; 0.2 x 10(9)/l, CD 4/8 ratio; 0.19) and positive serum HIV antibody revealed that his hypergammaglobulinemia and thrombocytopenia were resulted from HIV infection. The peripheral platelet count decreased to 28 x 10(9)/l at minimal point, however, it recovered to 160 x 10(9)/l within 7 months without treatment. His good performance status has been still maintained over 4 years. His whole clinical course suggests that there is no significant correlation between peripheral platelet counts, serum gammaglobulin levels or the amounts of PAIgG in this case. This case proposes that we should also consider a possibility of HIV infection for the patients showing hypergammaglobulinemia.

[The clinical significance of glycosylated ferritin in iron overloads and hematopoietic malignancies].

Serum ferritin concentration had been known to represent the amount of total body iron and has been clinically used as a parameter to evaluate the iron storage pool in a whole body. Glycosylated (secreted) and non-glycosylated (non-secreted) forms of serum ferritin (sFt) have been reported by others based on the difference in their affinity to concanavalin-A binding. In this report, we assessed the amount of glycosylated serum ferritin (Glyco-sFt) and the ratio (%) of Glyco-sFt/in hematopoietic disorders including iron overloads (n = 10), leukemias (n = 36), malignant lymphomas (n = 10), multiple myelomas (n = 3) and myelodysplastic syndromes (n = 12). A high percentage of Glyco-sFt was observed in normal healthy controls (n = 18, 78.1 +/- 7.4%) and iron-overloads (61.1 +/- 17.8%) as compared with that in hematopoietic malignancies (43.8 +/- 23.4%, p < 0.001). The amount of Glyco-sFt in iron-overloads was higher than that in hematopoietic malignancies with hyperferritinemia (p < 0.005). These data demonstrated that the same part of serum ferritin in hematopoietic malignancies was the non-secreted form and appeared to be derived from tumor cell lysis. We conclude that assessment of Glyco-Ft is a useful parameter to distinguish iron-overloads from malignant hematopoietic disorders both displaying hyperferritinemia.

[Enhanced sensitivity to cytosine arabinoside by combined stimulation of steel factor and GM-CSF in a factor-dependent leukemic cell line, MO7e--in terms of a possible clinical application to AML treatment].

In normal hematopoiesis, granulocyte macrophage-colony stimulating factor (GM-CSF) is known to stimulate the proliferation and differentiation of myelo-monocytoid lineage, while Steel factor (SLF) has been supposed to support the proliferation of more primitive hematopoietic progenitors including stem cells. We investigated the stimulatory effect of SLF and GM-CSF in twelve cases of acute myeloid leukemia (AML) cells in vitro by MTT assay. In 10 out of 12 cases, SLF or GM-CSF stimulated the proliferation of leukemic cells in short term liquid culture. In 7 out of these 10 cases, the leukemic cells responded to both cytokines. To investigate the possibility of the clinical application of these cytokines by combination with cell cycle-specific anti-tumor reagents, we assessed the effects of SLF and GM-CSF on the modulation of the cell cycle and sensitivity against cytosine arabinoside (ara-C) in a human factor-dependent leukemic cell line, MO7e. Flow cytometric analysis revealed the effect of cell recruitment into the cell cycle in the quiescent MO7e cells by exposure to these cytokines. The drug-sensitivity test using the MTT assay system demonstrated that pre-treatment with each cytokine enhanced sensitivity of ara-C. Furthermore, by combination of SLF and GM-CSF, the ara-C sensitivity was significantly wore graty enhanced than by each cytokine alone. These data suggest that combined pre-treatment with SLF and GM-CSF may provide new benefits for cure-oriented chemotherapy of AML followed by bone marrow transplantation or peripheral blood stem cell transplantation.

[Multicenter clinical evaluation of red cell concentrates stored up to 6 weeks in MAP, a new additive solution].

The clinical safety and efficacy of transfusion of red cell concentrates stored in MAP solution (MAP-CRC) containing mannitol, adenine, glucose, phosphate and citrate, into 39 anemic patients were evaluated. In 23 patients, infusion of MAP-CRC was alternated with infusion of ordinary CRC as a control. The MAP-CRC and CRC used in this study were stored at 4 degrees C for an average of 38.2 +/- 2.6 days (n = 52) and 18.1 +/- 2.2 days (n = 26), respectively. Red cell recovery was 77.5% for MAP-CRC and 82.5% for CRC, based on calculation of the increase in hemoglobin level one day after transfusion. There were no differences between patients transfused with MAP-CRC and those transfused with CRC in clinical findings or biochemical data. No major side-effects other than pyrexia associated with the underlying infections were seen in patients transfused with MAP-CRC. MAP-CRC stored up to 42 days is apparently as safe and effective as stored CRC. This new additive solution may therefore be useful for the future expansion of the indications for autologous blood transfusion by facilitating the collection and storage of more blood in the liquid state for a longer period, and may also be useful in obtaining more plasma from whole blood as source plasma.

[Mechanism of hyperferritinemia in a case of malignant histiocytosis].

We report a case of malignant histiocytosis diagnosed by liver-spleen biopsy under laparoscopy. A 49-year-old woman was admitted to our hospital with thrombocytopenia, moderate anemia and hypoproteinemia. Her bone marrow findings revealed erythroid and megakaryocyte hyperplasia, and the serum ferritin concentration was 2,250 ng/ml though she had not received any blood transfusions. Ferrokinetics analysis showed the pattern of ineffective erythropoiesis, and the half-lives of erythrocytes and platelets were both shortened. Her hepatosplenomegaly gradually increased accompanied by increasing serum ferritin level to 10,000 ng/ml. Liver-spleen biopsy was carried out under laparoscopy and revealed infiltration of atypical histiocytes with erythrophagocytosis, which were positive for S-100 and ferritin but negative for lysozyme. The rate of glycosylation in whole serum ferritin, analyzed by using concanavalin-A binding method, showed that her glycosylated ferritin content was only 8.3%, whereas in sera after iron overloading, it was about 70%. Serum isoferritin profiles by isoelectric focussing were studied, and isoferritin pattern from malignant histiocytosis was the same as that in iron overloading after neuraminidase treatment. These findings suggest that serum ferritin is synthesized in proliferating histiocytes and released in the plasma as a nonsecretory type (nonglycosylated ferritin) in this case.

[A clinical evaluation of injectable fluconazole in the treatment of deep mycosis associated with hematological malignancy].

The clinical efficacy and the safety of fluconazole as given at an intravenous dose of 100-400 mg daily were assessed in 7 patients with deep mycosis associated with hematological malignancy. Enrolled in the study were 1 patient with acute lymphatic leukemia, 1 with acute myelocytic leukemia, 2 with acute myelomonocytic leukemia, 2 with malignant lymphoma and 1 with myelodysplastic syndrome. Pathogens isolated from 4 patients were all Candida species including 2 Candida albicans, 1 Candida parapsilosis and 1 Candida krusei. Diagnoses of fungal infections of the patients were Candida pneumonia in 3 patients, candidemia in 1 and fungemia suggested in 3. Assessment of the clinical efficacy was made on 4 patients from whom pathogens were isolated. The global clinical improvement was good in 2 patients and fair in 1 with Candida pneumonia and good in 1 with candidemia. In the mycological assessment, pathogenic fungi were eradicated in 3 patients and decreased in 1 patient. No significant adverse reactions nor abnormality in clinical laboratory tests related with the dosing of fluconazole were observed in any of the patients.

[Syphilotherapy with amoxicillin, a synthetic penicillin (author's transl)].

Amoxicillin, a synthetic penicillin preparation, was given to 25 cases as an antiluetic. As for 13 cases of them, one year or more have passed since the treatment finished. 1. A daily dose of 1,000 approximately 1,500 mg of amoxicillin was continuously administered for 4 weeks, as one course. After each course finished, administrated was stoped for 2 approximately 4 weeks for examination of results of TPHA estimation, and then another course was started. 2. Effective rate in 13 cases reached about 40%. The remaining 12 cases are now under treatment. 3. Exanthema, a side effect, was observed in one of 25 cases.