Mechanistic studies of the biosynthesis of 3,6-dideoxyhexoses in Yersinia pseudotuberculosis. Purification and characterization of CDP-6-deoxy-delta 3,4-glucoseen reductase based on its NADH:dichlorophenolindolphenol oxidoreductase activity

CDP-6-deoxy-delta 3,4-glucoseen reductase, the key enzyme catalyzing the biosynthetic formation of CDP-ascarylose (CDP-3,6-dideoxy-L-arabino-hexose), was purified from Yersinia pseudotuberculosis by monitoring its NADH:dichlorophenolindolphenol oxidoreductase activity. A protocol consisting of DEAE-cellulose, phenyl-Sepharose, and Sephadex G-100 column chromatography yielded a mixture of two proteins. The low molecular weight protein contaminant was removed by limited tryptic digestion leaving a purified enzyme consisting of a single polypeptide with a molecular weight of 41,000. A weak, featureless uv spectrum above 300 nm suggested no common chromophoric cofactor contributes to enzyme activity and no protein-associated metals were detected. The stereospecificity of nicotinamide oxidation was determined to be pro-R stereospecific. Reduction of ferricyanide during NADH oxidation and confirmation of the intermediacy of O2- in the reaction flux suggested that enzyme-catalyzed H2O2 formation is not a direct two-electron reduction of molecular oxygen, but is rather the consequence of an enzymatic 2e-/1e- switch. The sugar deoxygenation reaction may therefore proceed through a radical mechanism.

Regulation of the redox potential of general acyl-CoA dehydrogenase by substrate binding

Significant thermodynamic changes have been observed for general acyl-CoA dehydrogenase (GAD) upon substrate binding. Spectroelectrochemical studies of GAD and several of its substrates have revealed that these substrates are essentially isopotential for chain lengths of C-4 to C-16 (E 0' =-0.038 to -0.045 V vs SHE). When GAD is bound by these substrates, a dramatic shift in the midpoint potential of the enzyme is observed (E 0' = -0.136 V for ligand-free GAD and -0.026 V for acyl-CoA-bound GAD), thus allowing a thermodynamically favorable transfer of electrons from substrate to enzyme. This contrasts with values reported elsewhere. From these data an isopotential scheme of electron delivery into the electron-transport chain is proposed.

Detection of beta-globin gene from single hairs

DNA can be extracted from hair shafts and hair roots. The content of DNA in hairs is usually limited: the root end of hairs may contain 0.5 micrograms DNA and shed hairs contain less than 10 ng DNA. DNA analysis with restriction fragment length polymorphism (RFLP) requires microgram amounts of DNA. Such DNA cannot be obtained from such samples as single hairs or blood stains. Even with a little amount of DNA, specific genes of DNA can be greatly amplified to more than 10(6)-fold in vitro by polymerase chain reaction (PCR). We extracted the DNA from a half, 1, and 2 hair roots and 4 hair shafts and amplified the DNA with primer pairs (5'-GCACCATTCTAAAGAATAAC-3', 5'-GGATTGTAGCTGCTATTAGC-3') of the beta-globin gene, covering part sequences of the IVS-2 region by using the polymerase chain reaction for 50 cycles. The electrophoresis of the PCR product revealed a 131 base pairs band. Finally, we hybridized the PCR product with an IVS-2 probe (5'-GGGTTAAGGCAATAGCAAT-3'). A fragment of the IVS-2 extending from nucleotide 612 to 742 of the beta-globin gene can be demonstrated in the slot blot filter of hair roots and hair shafts, but not in the 1 microgram of blood which was not amplified by PCR. Detection of the beta-globin gene from single hairs by using the PCR may be useful for the diagnosis of thalassemia from single hairs.

Natural killer cell activity in patients with hepatocellular carcinoma relative to early development and tumor invasion

To evaluate the significance of natural killer (NK) cell activity in the clinical assessment of patients with hepatocellular carcinoma (HCC), 32 patients combined with liver cirrhosis (LC) and HCC, and 29 LC patients were studied. The NK cell activity was markedly decreased in HCC patients and the LC group as compared with the control group, but there was no statistical difference between the NK cell activity of the HCC group and the LC group. The depression of NK cell activity in HCC patients was inversely correlated with the patient's age, and the HCC patients with venous invasion or with both lobes involved had lower NK cell activity. These results suggest that the decreased NK cell activity in HCC patients might be related to the coexistent liver disease, and marked decrease in NK cell activity might be one of the causes for the early development and invasion of HCC.

Erythrocyte complement receptor type 1 in non-SLE rheumatic diseases

An investigation was conducted to measure the levels of erythrocyte complement receptor type 1 (CR1) in patients with various rheumatic diseases other than systemic lupus erythematosus, and to evaluate the clinical significance of this receptor in patients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA). Erythrocyte CR1 was measured in 37 normal controls and 106 patients with various rheumatic diseases. The levels of erythrocyte CR1 decreased significantly in patients with AS, juvenile rheumatoid arthritis, Sjögren's syndrome, and RA, while there was no statistical difference in levels of erythrocyte CR1 between normal controls and patients with gouty arthritis. This suggests that erythrocyte CR1 deficiency may occur in immune-mediated rheumatic diseases such as crystal-induced arthritis. In this study, we noted that the levels of erythrocyte CR1 were not related to the disease activity and severity of AS. The levels of erythrocyte CR1 were also not correlated with the clinical and laboratory parameters of disease activity in RA patients. However, there was a negative association between the levels of erythrocyte CR1 and titer of rheumatoid factor in RA patients. Further study is needed to determine whether or not the level of erythrocyte CR1 is related to prognosis in patients with RA.

Natural killer cell activity in patients with hepatocellular carcinoma relative to early development and tumor invasion

To evaluate the significance of natural killer (NK) cell activity in the clinical assessment of patients with hepatocellular carcinoma (HCC), 32 patients combined with liver cirrhosis (LC) and HCC, and 29 LC patients were studied. The NK cell activity was markedly decreased in HCC patients and the LC group as compared with the control group, but there was no statistical difference between the NK cell activity of the HCC group and the LC group. The depression of NK cell activity in HCC patients was inversely correlated with the patient's age, and the HCC patients with venous invasion or with both lobes involved had lower NK cell activity. These results suggest that the decreased NK cell activity in HCC patients might be related to the coexistent liver disease, and marked decrease in NK cell activity might be one of the causes for the early development and invasion of HCC.

Chemotherapy for acute non-lymphocytic leukemia with low-dose cytosine arabinoside (Ara-C)

We administered low-dose cytosine arabinoside (Ara-C) to 32 newly diagnosed acute non-lymphocytic leukemia (ANLL) patients, 10 mg/m2 twice a day for 14-21 days, by subcutaneous injection or continuous intravenous infusion. CFU-GM of bone marrow cells were performed before low-dose Ara-C in some patients. Patients ranged in age from 21 to 78 years old. Ten showed complete remission and 16 partial response. The pretreatment CFU-GM pattern did not reflect the response to low-dose Ara-C. The major hematological effect of the treatment was myelosuppression, and most patients required platelet transfusion and the administration of antibiotics. Our study suggested that low-dose Ara-C treatment benefits some ANLL patients.

Myelodysplastic syndrome presenting with generalized cutaneous granulocytic sarcomas

A patient with myelodysplastic syndrome (refractory anemia with excess of blasts in transformation, RAEB-T) presented with generalized granulocytic sarcomas involving the skin. The diagnosis was confirmed by skin and bone marrow biopsies. Partial myeloperoxidase deficiency was noted in the circulating polymorphonuclear leukocytes and the more differentiated tumor cells in the granulocytic sarcoma. This observation suggests that such leukocytes may be derived from the abnormal 'leukemic' clone.

Purification of an acrosomal antigen recognized by a monoclonal antibody and antifertility effects of isoimmune serum

A highly conserved acrosomal antigen reactive to a monoclonal antibody (HS-63), generated against human sperm, was purified to homogeneity with a combination of conventional procedures and immunoaffinity chromatography using a soluble extract of mouse and rabbit testes. The molecular weight of the purified antigen was 42-50 kD when analysed by sodium dodecylsulphate polyacrylamide gel electrophoresis. The high specificity of the purified antigen to monoclonal antibody HS-63 was shown by indirect immunofluorescent inhibition assay, enzyme-linked immunosorbent assay, Western blot analysis and radioimmunosorbent assay. The purified antigen was used for isoimmunization of mice and rabbits. Following successive immunizations, antisera of high titres were raised and reacted specifically with antigen on the sperm acrosome and in testes of several mammalian species, but not with somatic tissues. These isoimmune sera exhibited strong inhibition on mouse in-vitro fertilization and human sperm penetration of zona-free hamster eggs. The results of this study suggest that the sperm-specific acrosomal antigen reacting with HS-63 could be a good candidate for the development of immunocontraceptive vaccines in humans and in other animals.

[A study of the effect of patient load and diseases upon resident training in a family medicine clinic]

Patient appointments and scheduling of patients and physicians are the first step in family medicine practice. The goals of outpatient services are to train the family physicians, to provide comprehensive and continuing health care for the family and its members. We evaluated the effect of the appointment system upon residents' training in a family medicine clinic of the Kaohsiung Medical College Hospital. The results were as follows: during the period between Aug. 1985 and Nov. 1986, a total of 2,220 patients and 5,891 out-patient encounters was recorded in this module. The subject age was mostly in the range of 16-64 years for all trainees. The distribution of the chronic diseases was relatively even for all except two trainees. For 4 residents, there were 40-60% more than the ideal patient numbers per session. This abnormal situation interferes with the normal functioning of family medicine clinics. The provocative results of this study suggest at least two important avenues for improvement. The first is to modify the appointment system. The second is to schedule the ideal amount of patients and kinds of diseases in order to provide comprehensive and continuous care for the family and its members.

Erythrocyte complement receptor type I in patients with hematologic diseases

Erythrocyte complement receptor type 1 (CR1) was measured in 37 normal controls and in 95 patients with various hematologic diseases. Levels of erythrocyte CR1 were significantly decreased in patients with acute myelocytic leukemia (AML), acute lymphocytic leukemia (ALL), chronic myelocytic leukemia, non-Hodgkin's lymphoma (NHL), aplastic anemia, idiopathic thrombocytopenic purpura, and multiple myeloma when compared to normal controls. There was also a trend of recovery of erythrocyte CR1 levels in AML and ALL patients when they were in a state of complete remission compared to those at time of onset or relapse. Further investigation is needed as to determine whether the level of erythrocyte CR1 can serve as a predictor for relapse of leukemia. This study also showed that the level of erythrocyte CR1 was not related to prognostic factors in NHL patients.

Spontaneous pneumothorax following chemotherapy for malignant thymoma with pulmonary metastasis: report of a case

Spontaneous pneumothorax is a rare complication in both primary and metastatic pulmonary neoplasms. Occasionally, pneumothorax is associated with chemotherapy of pulmonary malignancies. Pneumothorax after chemotherapy has been reported only in cases with osteogenic sarcoma, synovial sarcoma, fibrosarcoma, germinal tumors, and lymphoma with lung metastasis. We report a case of a patient with malignant thymoma who suffered from lung metastasis after radiation and adjuvant chemotherapy from lung metastasis after radiation and adjuvant chemotherapy (cyclophosphamide, adriamycin, and cis-platinum). A chest X-ray taken 2 days after chemotherapy showed bilateral pneumothorax, which was resolved with conservative treatment. The pneumothorax in this patient is believed to have been caused by the rupturing of the tumor into the pleural cavity and the bronchi.

[A case report of carotenemia]

Carotenemia is a common disease in children, and it is mainly due to excessive intake of food enriched with carotene. A fourteen-year-old girl, whose skin had been discolored yellow for several months, was brought to Kaohsiung Medical College Hospital for examination. Physical examination revealed she had a marked yellow color skin, especially on the palms and soles; conjunctiva was not anemic; sclera was not icteric; breath and heart sounds were normal; liver and spleen were not enlarged. Laboratory examination revealed normal results for the liver function test, however, serum carotene was elevated to 460 micrograms/dl in contrast to 80 micrograms/dl from a same-aged healthy child as a control (normal range of the serum carotene: 50-250 micrograms/dl). Tracing back her past history, she had taken a lot of oranges daily for more than one year. After consulting a nutritionist and changing her eating habits to a balanced diet for eight weeks, the serum carotene level decreased to 270 micrograms/dl (same-aged healthy child: 30 micrograms/dl). The skin color was also improved.

Pneumocystis Carinii pneumonia in an AIDS patient with dramatic response to inadvertent steroid therapy--a case report

A 28 year-old homosexual man had one month history of intermittent high fever, nonproductive cough and progressive shortness of breath. He not only had immunity deficits, with decrease CD4 cells decreased CD8 cells and inverted CD4/CD8 ratio, but also presented with evidence of human immunodeficiency virus infection (positive ELISA antibody tests and Western blot tests). Chest X-ray showed diffuse pulmonary infiltration. The arterial blood gases revealed hypoxemia. The PaO2 was 69 mmHg. Spirometry showed FVC 2.28 L (45% predicted), FEV1 2.21 L (49% predicted), FEV1/FVC 93%, and MMEF 4.41 L/sec (90% predicted). The configuration of the Flow-Volume loop was consistent with a restrictive ventilatory defect. Transthoracic lung biopsy demonstrated pneumocystis carinii pneumonia (PCP). He had inadvertent steroid therapy and showed some clinical, pulmonary function and chest X-ray improvement before the diagnosis was established. Steroids might be as adjunctive therapy for a short period of time in treatment of PCP associated with acquired immunodeficiency syndrome (AIDS) at respiratory failure.

The reappraisal of dilute tissue thromboplastin inhibition test in the diagnosis of lupus anticoagulant

The dilute tissue thromboplastin inhibition (DTTI) test (Schleider et al, 1976) is a sensitive but non-specific test for lupus anticoagulant (LA). False positive results are seen in patients with clotting factor deficiency involving the extrinsic pathway and also in some patients with specific factor inhibitors (Triplett et al, 1983; Rosove et al, 1986). Since the effect of LA is phospholipid dependent but those of factor deficiency and specific inhibitors are not, we analyse the test results by comparing the degree of inhibition using different dilutions of tissue thromboplastin and express it as the DTTI index. This is defined as the clotting time ratio with 0.2% tissue thromboplastin divided by the clotting time ratio with 2% tissue thromboplastin. We also perform a dilute tissue thromboplastin time with platelet substitution to see if this could neutralize the inhibition caused by LA. Both of these modifications can reliably distinguish LA from other conditions associated with prolonged APTT better than the original DTTI test.

Circulating immune complexes in patients with hematologic diseases

Circulating immune complexes (CIC) were measured by C1q-solid phase method in ninety-five patients with various hematologic diseases. The results showed significantly higher CIC levels in patients with acute myelocytic leukemia, chronic myelocytic leukemia, aplastic anemia and idiopathic thrombocytopenic purpura (ITP) than CIC levels in normal controls. However, there was no significant difference in such levels in patients with acute lymphocytic leukemia, non-Hodgkin's lymphoma and multiple myeloma when compared to normal controls. In this study, the level of CIC did not relate to prognosis for patients with non-Hodgkin's lymphoma. The findings demonstrated that a high level of CIC in patients with ITP usually responded poorly to steroid treatment. Other immunosuppressive agents were indicated in these cases. Therefore, the CIC level may serve as a therapeutic guide for the treatment of patients with ITP.

Soluble interleukin-2 receptor levels in cerebrospinal fluid of patients with acute lymphocytic leukemia or with non-Hodgkin's lymphoma

An elevated serum soluble interleukin-2 receptor (SIL-2R) has been noted in various hematological malignancies and conditions associated with active T-cell responses. Its appearance has also correlated with disease activity and tumor burden. Since few studies have been reported concerning SIL-2R in cerebrospinal fluid (CSF), work was undertaken to try to find if SIL-2R could be detected in the CSF of patients with acute lymphocytic leukemia (ALL) or non-Hodgkin's lymphoma (NHL), and whether it could become a clinical predictor of the central nervous system (CNS) involvement, and its response to therapy. Preliminary results showed that 1) the CSF SIL-2R is usually detectable in very low level with a mean of 15.1 +/- 14.2 units/ml compared with the mean serum level of 338.3 +/- 135.5 units/ml in eight normal controls; 2) there was no significant difference in the mean serum and CSF SIL-2R in five patients with ALL in a complete remission state compared with normal controls, while two ALL patients with CNS relapse and two NHL patients with CNS involvement had high levels of SIL-2R in CSF. High serum and low CSF SIL-2R levels were noted in another ALL case suffering from bone marrow relapse but without CNS relapse. It was also noted that decreased CSF SIL-2R concentration occurred subsequent to intrathecal chemotherapy in two ALL patients. From these results, we conclude that CSF SIL-2R might become a useful indicator of CNS involvement in patients with hematological malignancies and may predict response to chemotherapy.

Clinical observations of virologically confirmed dengue fever in the 1987 outbreak in southern Taiwan

Fifty-nine virologically confirmed cases of dengue fever were clinically studied during the 1987 outbreak in southern Taiwan. Viral isolation and serologic studies indicated that type 1 dengue was the cause. Dengue fever has not been on the island of Taiwan for 42 years and nearly all the population under 42 years of age is susceptible. Most patients under age 42 experience primary infection while those over 42 years old experience secondary infection. The majority of 59 cases studied were females in the 21-30-year age group. Classic signs and symptoms ere fever, headache, muscle pain, joint pain, nausea and vomiting, and skin rash. Approximately 80% of the patients had leukopenia (less than 5,000/mm3) and thrombocytopenia (less than 50,000/mm3) and 90% experienced mild to moderate elevation of serum glutamic oxaloacetic transaminase. Hemorrhagic manifestations occurred in 25.4% of patients. No patients under observation in this study developed hypotension or died.

[Hematological aspects of dengue fever]

Fifty patients with dengue fever from Sept. 1987 to Jan. 1988 were studied for hematological features. The lowest blood counts values throughout the course of illness were Hb: 13.2 +/- 1.9 gm/dl, WBC: (2.77 +/- 1.63) x 10(3)/mm3, Platelet: (8.7 +/- 5.5) x 10(4)/mm3. Leukopenia (WBC less than 4000/mm3) was present in 38 (76%) of the cases and thrombocytopenia (platelet less than 10 x 10(4)/mm3) in 27 (54%) of the cases. Leukocytes reached nadir (1000-2000/mm3) at the 5th-6th day after fever onset, thrombocytes reached nadir (2.0-5.0 x 10(4)/mm3) at the 5th-7th day after fever onset. Bone marrow studies showed mild hypocellularity in the acute stage (less than 1 week) and normal cellularity in the convalescent stage (greater than 1 week). Megakaryocytes increased with various stages of maturation of megakaryocytes appearing in a majority of patients. Nuclear vacuolization of megakaryocytes could also be found. Bone marrow CFU-GM when performed within one week of illness showed no growth or low colony count, and was nearly normal after one week of fever onset. This study may suggest that leukopenia in dengue fever may be caused by virus-induced destruction or inhibition of myeloid progenitor cells. Thrombocytopenia may result from by destruction of peripheral platelet or bone marrow megakaryocytes by viruses which consequently reduce the platelet production.