High affinity interaction of mammalian DNA topoisomerase I with short single- and double-stranded oligonucleotides

The interaction of DNA topoisomerase I (topo I) with a set of single- and double-stranded oligonucleotides containing 5-27 mononucleotides was investigated. All single- and double-stranded oligonucleotides were found to inhibit competitively the supercoiled DNA relaxation reaction catalyzed by topo I. The enzyme affinity for specific sequence pentanucleotides of the scissile (GACTT, Ki = 2 microM) and non-cleaved chain (AAGTC, Ki = 110 microM) is about 2-4 orders of magnitude higher than that for non-specific oligonucleotides. This specific sequence affinity increases in several cases; lengthening of single-stranded oligonucleotides, formation of stable duplexes between complementary oligonucleotides and preincubation of the enzyme with ligands before addition of supercoiled DNA. We assume that oligonucleotides having a high affinity to the enzyme can offer a unique opportunity for rational design of topoisomerase-targeting drugs.

Establishment and characterization of IRTA17 and IRTA21, two novel acute non-lymphocytic leukaemia cell lines with t(16;21) translocation

The t(16;21)(p11;q22) translocation is an infrequent chromosomal abnormality, but seems specific to acute non-lymphocytic leukaemia (ANLL). We established two cell lines with t(16;21)(p11;q22) from the bone marrow of a patient with ANL in relapse. Their morphological, karyotypic, immunohistochemical and genetic features are examined. Although both cell lines show monocytoid features morphologically, they express only CD13 (My7) and CD34, and neither expressed monocytoid or lymphoid markers. Reverse transcription-polymerase chain reaction showed that both cell lines expressed a similar TLS-ERG chimaeric mRNA as a result of the t(16;21)(p11;q22) translocation. As far as we know, there is no report of a leukaemia cell line with t(16;21). These cell lines represent a useful tool for leukaemia research.

Simultaneous determination of ascorbic acid and dehydroascorbic acid in fish tissues by high-performance liquid chromatography

An high-performance liquid chromatographic method with post-column derivatization has been developed for the simultaneous determination of ascorbic acid (AA) and dehydroascorbic acid (DHAA) in fish tissues. Extracted AA and DHAA were separated by a Shim-pack SCR-1O1H column within 20 min, reacted with sodium hydroxide containing sodium borohydride and monitored at 300 nm. The detection limits for both AA and DHAA were 0.1 microgram/ml.

Isolation of cDNAs for mouse phenol and bilirubin UDP-glucuronosyltransferases and mapping of the mouse gene for phenol UDP-glucuronosyltransferase (Ugtla1) to chromosome 1 by restriction fragment length variations

The mouse gene for phenol UDP-glucuronosyltransferase (UDPGT; Ugtla1) was mapped at 42 cM on chromosome 1, a position identical to that of the gene for bilirubin UDPGT (Ugtla1), from linkage analysis of a three-point cross test with Idh-1, En-1, and Ugtla1 as marker genes. The cDNAs for mouse phenol and bilirubin UDPGTs, isolated after amplification by PCR, shared an identical 3'-half region. Our results strongly suggest that mouse bilirubin and phenol UDPGTs are expressed from a single gene and involve alternative splicing events. We also detected duplication of the gene for phenol UDPGT in all mouse strains examined with the exception of MOL-MIT and SUB-SHH.

Urinary sediment analyzed by flow cytometry

A flow cytometer for the automated analysis of urinary sediment was designed, and its performance was examined by the evaluation of 821 specimens. Auramine O, a dye for DNA and RNA, was used for the staining of the sediment. Urine (5 ml or more) was processed by the instrument for sediment analysis. Conventional microscopic analysis was done for comparison. The RBC count, the WBC count, and the number of bacterial cells, epithelial cells, and casts found by the flow cytometer and by microscopy were compared. Correlation was high for all these results. The overall sensitivity, specificity, and efficiency (accuracy) in the items analyzed were 84.7%, 57.8%, and 67.2%, respectively. One hundred specimens could be analyzed by the instrument per hour. The instrument seemed useful for screening for urinary tract disorders to identify specimens that should be analyzed microscopically in routine laboratories.

Demonstration of axon collateral projections from the substantia nigra pars reticulata to the superior colliculus and the parvicellular reticular formation in the rat

It was revealed in the rat that single neurons in the substantia nigra pars reticulata (SNr) innervated both the superior colliculus (SC) and the parvicellular reticular formation (RFp) in the pons and medulla oblongata by way of axon collaterals. After injecting Fluoro-gold into the lateral part of the SC and Fluoro-ruby into the RFp on the same side, some SNr neurons were double-labeled with both tracers. They were localized in the dorsolateral part of the caudal half of the SNr ipsilateral to the injection sites.

[Anesthesia in a patient with epidermolysis bullosa]

A 6-year-old-boy with epidermolysis bullosa underwent plastic surgeries for the scar contraction of hands. Anesthesia was induced with inhalation of sevoflurane in combination with nitrous oxide and oxygen. The tracheal was not intubated. Anesthesia was maintained with sevoflurane, nitrous oxide and oxygen with continuous intravenous infusion of ketamine. The courses of anesthesia and the operations were uneventful. The most important point in the anesthetic management of the patient with this disease is to avoid mechanical stimulation to skin and mucous membrane.

[Detected Epstein-Barr virus genome using polymerase chain reaction in peripheral mononuclear cells--subacute necrotizing lymphadenitis]

A 23-year old woman was admitted to our hospital because of fever, leukocytopenia, thrombocytopenia and cervical lymphadenopathy. From pathological findings of the cervical lymphnode she was diagnosed as subacute necrotizing lymphadenitis (SNL). Bone marrow aspiration was hypocellular with proliferation of mature histiocytes with hemophagocytosis. Lactate dehydrogenase was elevated to 1863 IU/l and mild liver dysfunction was observed. Hepatosplenomegaly, lymphnode swelling in abdominal cavity, pleural effusion and pericardial effusion were detected. After glucocorticoid therapy all such disorders were normalized. In this course, Epstein-Barr (EB) virus genome was detected by a polymerase chain reaction method from peripheral mononuclear cells. After normalization, EB virus genome became not to be detected. From present case we concluded that EB virus was expanded in clinical course and was associated with pathogenesis of SNL.

Ultrastructural study on NOS-immunoreactive nerve terminals in the rat coeliac ganglion

Nerve terminals immunoreactive for nitric oxide synthase (NOS) were studied in the rat coeliac-superior mesenteric ganglion by electron microscopy using a pre-embedding immunostaining method. The immunoreactive material was distributed in the axoplasmic matrix and was not specifically associated with any subcellular organelle. In most NOS-immunoreactive axon terminals numerous small clear vesicles (35-50 nm) were seen, and in some terminals a small number of large granular vesicles (70-120 nm) were intermingled with small clear vesicles. Most NOS-immunoreactive axon terminals formed axodendritic as well as axo-somatic synapses with non-immunoreactive ganglion neurones, and axo-axonic contacts were very scarce. These results suggest that NO may be released at the synaptic sites from the axon terminals and may affect ganglion neurones.

Descending projections from the superior colliculus to the reticular formation around the motor trigeminal nucleus and the parvicellular reticular formation of the medulla oblongata in the rat

We observed by the anterograde and retrograde tracing techniques in the rat that the lateral part of the superior colliculus (SC), where the nigrotectal fibers from the dorsolateral part of the substantia nigra pars reticulata (SNr) terminated, sent projection fibers to the reticular region around the motor trigeminal nucleus (RFmt) and parvicellular reticular formation (RFp) of the medulla oblongata, where many premotor neurons for the orofacial motor nuclei were known to be distributed. The SC neurons sending their axons to the RFmt and RFp were mainly located in the stratum griseum intermedium, and additionally in the stratum griseum profundum. Our results suggest that neuronal signals conveyed through the nigro-tecto-bulbar pathway to the RFmt and RFp may exert control influences upon oral behavior.

A high alpha-linolenate diet suppresses antigen-induced immunoglobulin E response and anaphylactic shock in mice

Mice were fed for 2 mo diets having ratios of alpha-linolenate [18:3 (n-3)] to linoleate [18:2(n-6)] of < 0.01, 0.36, 1.0 and 3.9. Proportions of safflower seed oil and perilla seed oil were adjusted to obtain these ratios. The dietary alpha-linolenate to linoleate balance was reflected in the proportion of (n-3) and (n-6) highly unsaturated fatty acids with 20- and 22-carbon chains in spleen phospholipids, but the ratio did not affect the proportion of T lymphocyte subsets expressing CD4 and CD8 antigens in splenic leukocytes. The immunoglobulin (Ig) G and IgM responses against sheep red blood cells when estimated as plaque-forming cells present in spleen, were not affected significantly by the diets. However, the serum hemagglutinin titer was slightly but significantly higher in the high alpha-linolenate diet group [18:3(n-3)/18:2(n-6) = 3.9] than in the dietary group with 18:3(n-3) to 18:2(n-6) ratios of 0.36 and < 0.01. In contrast, the IgE antibody response against egg albumin, as well as the mortality from anaphylactic shock induced by a second challenge with antigen, was significantly lower in the high alpha-linolenate diet group [18:3(n-3)/18:2(n-6) = 3.9] than in the high linoleate diet [18:3(n-3)/18:2(n-6) < 0.01] group. These results, together with the reported suppressive effects of a high alpha-linolenate diet on the formation of lipid-derived allergic mediators, support the hypothesis that raising the (n-3) to (n-6) ratios of diets would be effective in reducing the severity of immediate-type allergic hypersensitivity.

[Partial resection of superior vena cava using two stage venous return catheter for a new application]

A case of invasive lung cancer was reported, in which operation partial resection and reconstruction of the invaded superior vena cava (SVC) was performed. During procedure in SVC, a two stage venous return catheter, which is ordinary used in cardiac operations, was used as a temporary SVC-right atrial internal bypass. This new application of the catheter was convenient and effective for resection and reconstruction of SVC.

Action spectrum for bergamot-oil phototoxicity measured by sunburn cell counting

The present study investigated the phototoxic effect of bergamot oil and its photosensitive component, bergapten, on sunburn cell (SBC) production in guinea pig skin. The back skin was pretreated with bergamot oil or bergapten and exposed to monochromatic light under various conditions. After irradiation, skin specimens were excised, and histological sections were prepared. The number of sunburn cells in the interfollicular epidermis was counted. The SBC formation by bergamot oil or bergapten plus UVB radiation was the same as that without pretreatment with any photosensitizer. In contrast, a significant number of SBCs were induced by bergamot oil or bergapten plus UVA radiation, but no SBCs were found after the treatment with UVA alone. The result indicates that bergamot oil or bergapten was photosensitized by UVA irradiation. The SBCs were linearly increased in a UV-dose dependent manner. On the basis of the regression lines, an action spectrum and spectral peak for the photosensitizers plus UVA were obtained. The action spectrum for bergamot oil- and bergapten-induced SBC formation was in the ranges of 325-365 nm and 325-350 nm, and their spectral peaks were at 335-345 nm and 335-350 nm, respectively. The data are in good accordance with those estimated from skin erythema reactions. Therefore, counting SBCs is a very useful parameter for quantitative evaluation of phototoxicity.

Distribution of substance P immunoreactive nerve fibers in the tracheal submucosal gland of cats

Immunohistochemistry combined with electron microscopy was employed to investigate the distribution of substance P-immunoreactive (SP-IR) nerve fibers in the tracheal submucosal gland of cats. The SP-IR nerve fibers were found to form a network around the glands. Numerous varicosities were also detected within the basement membrane of the acini and secretory tubules. All the intraglandular varicosities showed close spatial contact with serous cells, mucous cells, and myoepithelial cells. Our findings suggest that substance P-induced mucus secretion from tracheal submucosal glands in cats may be caused not only by a glandular contractile response of myoepithelial cells, but also by direct stimulation to both serous and mucous cells.

Respiratory activities in relation to external glossal muscles

In this study, the activities of the two external glossal muscles, Genioglossus (Gg) and Styloglossus (Sg), related to respiration were examined through the electromyography (EMG) in dog. During quiet breathing, no phasic respiratory activity were observed in either muscle. With hypercapnic condition induced by closed rebreathing respiratory system, both Sg and Gg showed phasic respiratory activities in respiration period. At first inspiratory EMG activity was observed from Sg (PaCO2 > 50 mmHg), then after a while from Gg (PaCO2 > 55 mmHg). NaCN injection bilaterally to the carotid body enhances the inspiratory ENG activities in both muscles. Sg was more sensitive than Gg to respiratory stimulation such as hypercapnia or NaCN injection.

Neurons in the intertrigeminal region of the rat send projection fibers to the superior colliculus

A retrograde WGA-HRP and anterograde PHA-L study in the rat indicated that many neurons in the intertrigeminal region (ITR) sent their axons to the superior colliculus (SC), bilaterally with a clear-cut contralateral dominance. These neurons were small to medium in size and their axons terminated in the lateral part of the SC, especially in the stratum griseum intermedium.

[Adult T cell leukemia/lymphoma effectively treated with chronic oral etoposide]

A 52-year-old man, who complained of tarry stool and systemic lymphadenopathy, was admitted to our hospital on July 2, 1992. Biopsy showed diffuse large cell lymphoma. Leukocytosis with atypical lymphocytes was not shown in the peripheral blood, but there was an elevated serum LDH level. The man was found to have both HTLV-I antibody and the monoclonal integration of proviral DNA in malignant lymph node cells obtained at biopsy. The diagnosis was lymphoma-type adult T-cell leukemia (ATLL). The chemotherapy regimens of MI-FP, CHOP and modified DHAP were used for the treatment, but were not effective. So, he was treated with etoposide 75 mg orally for 25 days (chronic oral etoposide therapy) and achieved partial remission. This chemotherapy induced myelosuppression with neutropenia, but there was no documented infection. Chronic oral etoposide therapy is an effective regimen for patients with relapse or refractory lymphoma.

[Standardization in flow cytometry]

Analysis of lymphocyte subsets and determination of leukemic cells by flow cytometry has now become an important clinical test. With recent technological developments, reliability was improved and the procedure became easier. To establish quality assurance procedures for flow cytometry, standardization is necessary. In the United States, the National Committee for Clinical Laboratory Standards (NCCLS) has been working actively and has published several tentative guidelines. However, in Japan, such work lags behind that in western countries. The results of quality control surveys show that differences in data exist among instruments and laboratories. To minimize such differences, nation-wide surveillance must be established. Also, efforts should be made to establish reference methods and reference materials that will lead to standardized results. We hope standardization will ensure precision and accuracy in flow cytometric results in clinical laboratories.

[CSF in laboratory medicine]

The effect of granulocyte-colony stimulating factor (G-CSF) or macrophage-colony stimulating factor (M-CSF) on patients with malignant lymphoma was analyzed. G-CSF was administered for ten days after conventional chemotherapy causing an increase in the granulocyte and monocyte counts. The increase in these cells shortened the duration of a leukocyte count lower than 2000 or 3000/mm3. There were no detectable effects from G-CSF on other blood cells. M-CSF had no effect on any of these cells. Receptors of these cytokines on various types of leukemic cells were also analyzed by flow-cytometry using fluorescent isothianate-labelled G-CSF or M-CSF. With this simplified method, G-CSF receptors were detected on almost all of the myeloid acute leukemia cells, but not on the nonmyeloid leukemic cells. M-CSF receptors were also detected on all of the monocytic acute leukemic cells, but not on myelocytic or lymphocytic leukemic cells.

Cloning of the mouse cDNA encoding DNA topoisomerase I and chromosomal location of the gene

The mouse cDNA encoding DNA topoisomerase I (TopoI) was cloned and the nucleotide sequence of 3512 bp was determined. The cDNA clone contained an open reading frame encoding a protein of 767 amino acids (aa), which is 2 aa longer than its human counterpart. Overall aa sequence homology between the mouse and human, and between the mouse and yeast (Saccharomyces cerevisiae) sequences was 96% and 42%, respectively. The mouse TopI gene was mapped at position 54.5 on chromosome 2 from linkage analyses of a three-point cross test with Geg, Ada, and a as marker genes.

[Isospora belli infection in a patient with adult T cell leukemia]

A 53-year-old man was hospitalized for the development of watery diarrhea associated with decreased appetite and progressive weight loss and was found to have leukocytosis. The white blood cell count was 14,600/microliters with 66 percent abnormal lymphocytes. Serum anti-HTLV-I was positive and monoclonal insertion of HTLV-I provirus into the atypical cell genome was confirmed with the southern blotting hybridization technique. A diagnosis of ATL was made. Examination of fresh stool specimens revealed Isospora belli (I. belli) oocysts. Initial treatment for I. belli consisted of oral trimethoprim 160mg and sulfamethoxazole 400mg given twice daily for nine days. Diarrhea ceased within 2 days of the start of treatment, but I. belli oocysts were again detected after 20 days. Trimethoprim 160mg and sulfamethoxazole 400mg were reinstituted four times daily for 10 days, and then twice daily for 21 days. The clinical response was again dramatic, with rapid clearance of oocysts from the stool. There has been no recurrence of diarrhea. The patient's leukemia was refractory to chemotherapy; the white blood cell count continued to rise, pneumonia developed, and the patient died. I. belli is a previously unrecognized opportunistic pathogen that must be considered in the clinical setting of chronic diarrhea in patients with ATL.

Immunohistochemical and electron microscopic studies of substance P in guinea pig nasal glands

The distribution of substance P-like immunoreactive (SP-IR) nerve endings in the nasal gland of the guinea pig was studied by using histochemical techniques to detect mucous glycoprotein and immunohistochemical techniques for SP, in combination with electron microscopy. Most nasal glands were negative for both AB and periodic acid-Schiff (PAS) staining. The SP-IR nerve fibers were found to form a network around these glands. The SP-IR nerve endings were located in the region between interdigitated cytoplasmic folds of acinar cells and along the cell surface, as well as in the intercellular spaces of proximal ducts. The acini which closely contacted with SP-IR nerve endings were serous in type. Our results suggest that substance P may contribute to the regulation of serous gland secretion in the guinea pig nasal mucosa.