Immunocytochemical detection of Ca2+-dependent subspecies of protein kinase C in mouse embryos before and during compaction

Summary To confirm the possibility that protein kinase C is involved in compaction of mouse embryos, the presence and distribution pattern of Ca²⁺-dependent subspecies of this enzyme in mouse embryos, before and during compaction, were examined immunocytochemically with three different monoclonal antibodies. These were MC-1a, MC-2a and MC-3a, which selectively interact with the subspecies of the enzyme known as types I, II and III, respectively. Only when embryos were incubated with MC-3a, was immunofluorescence clearly detected in all cells of embryos before and during compaction. This result demonstrates the presence of type III protein kinase C in embryos before and during compaction and suggests the possibility that the type III enzyme may be involved in compaction. No marked differences were found in the distribution pattern of the type III enzyme between embryos examined before and during compaction.     

A Novel Assay System for Anti-Human Immunodeficiency Virus Type 1 (HIV-1) Activity Using a Subclone of a Monocytic Cell Line,U937

A subclonal cl.1–14 cell was established from a monocytic cell line U937 by a limiting dilution method. The anti-HIV-1 activity of some antiviral compounds was evaluated in HIV-1-infected cl.1–14 cells. The results demonstrated that although AZT was a potent inhibitor of HIV-1 replication in cl.1–14 cells, its 50% effective concentration (EC₅₀) values was 80 times higher than that in HIV-1 infected MT-4 cells; the EC₅₀ of AZT was 0.16 μM and 0.002 μM in cl.1–14 and MT-4 cells, respectively. In contrast, the anti-HIV-1 activity of ddA, ddI and ddC in cl.1–14 cells was comparable to that in MT-4 cells. The antiviral activity of nevirapine, dextran sulfate, curdlan sulfate and T22 did not differ significantly between the cl. 1–14 and MT-4 cells. The antiviral activity of several compounds in the HIV-1-infected cl.1–14 cells was similar to that in the HIV-1jr -fl -infected human peripheral macrophages. Our results suggest that cl.1–14 cell cultures are very useful for estimating antiviral activity and more advantageous than the use of peripheral blood macrophages.     

Restriction Fragment Length Polymorphism (RFLP) of Genomic DNA of Moraxella (Branhamella) catarrhalis Isolates in a Hospital

Epidemiological typing, based on restriction fragment length polymorphism (RFLP) by pulsed-field gel electrophoresis (PFGE), was attempted for the 38 clinical isolates of Moraxella catarrhalis obtained at Shinshu University Hospital during the years 1987 and 1993. Digestion with SmaI or NotI generated well separable, 12 to 5 genomic DNA fragments ranging from 1,000 kb to 30 kb and the strains could be classified into 14 or 13 types, respectively. The electrophoretic profile differed with the strain in most of them and was hence useful to distinguish the each strain. Investigation for their RFLP have, however, suggested that majority of them, including the type strain ATCC25238, may have derived from a common ancestor.     

A comparative study of floral development inTrillium apetalon andT. kamtschaticum (Liliaceae)

Trillium apetalon Makino is unique amongTrillium in having apetalous flowers. Using scanning electron microscope, the early floral development was observed in comparison with that ofT. kamtschaticum Pallas ex Pursh having petalous flowers. Morphologically petal primordia closely resemble stamen primordia in their more or less narrow and radially symmetric shape and are clearly distinct from sepal primordia with broad bases. Early in floral development sepal primordia are first initiated and subsequently two whorls of three primordia each are formed in rapid sequence, the first three at the corners and the second three at the sides of the triangular floral apex. Based on comparison in position and early developmental processes of their primordia, petals and outer stamens ofTrillium kamtschaticum are equivalent to outer stamens and inner stamens ofT. apetalon. The replacement of petals by outer stamens apparently leads to the loss of petals inTrillium apetalon flowers. Such a replacement can be interpreted in terms of homeosis. The replacement of the petal whorl leads to the serial replacement of the subsequent whorls: outer stamens by inner stamens, and inner stamens by gynoecium inTrillium apetalon. The term ‘serial homeosis’ is introduced for this serial replacement.     

Synthesis of sulfated derivatives of curdlan and their anti-HIV activity

Sulfopropyl curdlan was synthesized, its structure was determined, and the anti-HIV activity was compared with that of standard curdlan sulfates obtained with piperidine N-sulfonic acid in dimethyl sulfoxide. It was shown that sulfopropyl curdlan exhibits weaker anti-HIV activity than curdlan sulfate. Curdlan sulfates were synthesized with a SO₃-pyridine complex in a heterogeneous phase. It was shown from ¹³C-NMR spectra of acetylated curdlan sulfates that they had a different substituent distribution from standard curdlan sulfate. The cytotoxicity of the curdlan sulfates was attributed to their heterogeneous structure.     

Extra-weak chemiluminescence of drugs XV. Method for determining stability of Toki-shakuyaku-san extract granules

The purpose of the study was to evaluate the quality of Toki-shakuyaku-san extract granules (TJ-23) using chemiluminescence (CL). A linear relationship was obtained between the log value of the CL of TJ-23 and the reaction temperature. An excellent correlation (r= 0.999) was found between the slope of this curve (ΔA) and the colour intensity due to the browning reaction occurring at the early stage of the Maillard reaction.     

Determination of a new immunosuppressant, mycophenolate mofetil, and its active metabolite, mycophenolic acid, in rat and human body fluids by high-performance liquid chromatography

Mycophenolate mofetil, a new immunosuppressant, is a morpholinoethyl ester of mycophenolic acid. A new selective, sensitive and simple high-performance liquid chromatographic method was developed for the determination of mycophenolic acid and mycophenolate mofetil in biological samples. The preparation of samples was based on liquid—liquid extraction. The compounds were separated on a CN column using acetonitrile—0.01 M phosphate buffer (1:4, v/v) as the mobile phase. UV detection was used at wavelengths 215 and 304 nm. The detection limit was 5 ng per injection volume. This method enabled pharmacokinetic and pharmacodynamic studies in humans and rats.     

Carbon uptake in Eurasian boreal forests dominates the high-latitude net ecosystem carbon budget

Arctic-boreal landscapes are experiencing profound warming, along with changes in ecosystem moisture status and disturbance from fire. This region is of global importance in terms of carbon feedbacks to climate, yet the sign (sink or source) and magnitude of the Arctic-boreal carbon budget within recent years remains highly uncertain. Here, we provide new estimates of recent (2003–2015) vegetation gross primary productivity (GPP), ecosystem respiration (R_eco), net ecosystem CO₂ exchange (NEE; R_eco − GPP), and terrestrial methane (CH₄) emissions for the Arctic-boreal zone using a satellite data-driven process-model for northern ecosystems (TCFM-Arctic), calibrated and evaluated using measurements from >60 tower eddy covariance (EC) sites. We used TCFM-Arctic to obtain daily 1-km² flux estimates and annual carbon budgets for the pan-Arctic-boreal region. Across the domain, the model indicated an overall average NEE sink of −850 Tg CO₂-C year⁻¹. Eurasian boreal zones, especially those in Siberia, contributed to a majority of the net sink. In contrast, the tundra biome was relatively carbon neutral (ranging from small sink to source). Regional CH₄ emissions from tundra and boreal wetlands (not accounting for aquatic CH₄) were estimated at 35 Tg CH₄-C year⁻¹. Accounting for additional emissions from open water aquatic bodies and from fire, using available estimates from the literature, reduced the total regional NEE sink by 21% and shifted many far northern tundra landscapes, and some boreal forests, to a net carbon source. This assessment, based on in situ observations and models, improves our understanding of the high-latitude carbon status and also indicates a continued need for integrated site-to-regional assessments to monitor the vulnerability of these ecosystems to climate change.     

Antiviral Activity of 1-β-D-Arabinofuranosyl-E-5-(2-Bromovinyl)Uracil against Thymidine Kinase Negative Strains of Varicella-Zoster Virus

Mechanism of antiviral activity of 1-β-d -arabinofuranosyl-E-5-(2-bromovinyl)uracil (BV-araU) against the YSR strain of varicella-zoster virus (VZV), which is a mutant derived from the wild YS strain and is completely deficient in viral thymidine kinase (TK), was searched in comparison with antiviral activity of other thymidine analogues, guanosine analogue and thymidylate synthase (TS) inhibitor in human embryo lung fibroblast cells. Thymidine analogues, such as BV-araU, 5-iododeoxyuridine (IUDR), 1-β-d -arabinofuranosylthymine (araT), and guanosine analogue, such as 9-(2-hydroxyethoxymethyl)guanine (ACV), showed higher antiviral activity to the YS strain than to the YSR strain. Though, BV-araU also had the antiviral activity of a microgram level against the YSR strain. In contrast to these results, TS inhibitor, 5-fluorodeoxyuridine (FUDR), had higher antiviral activity to the YSR strain than to the YS strain. Highly synergistic antiviral activities of FUDR to the YS strain and the YSR strain were observed in combination with IUDR, araT, or ACV. However, weakly synergistic or additive inhibition to the YSR strain was shown in combination of BV-araU and FUDR, in spite of highly synergistic effect of this combination to the YS strain. The viral and cellular TS activity was partially inhibited by BV-araU monophosphate, but not by BV-araU. These results indicate that BV-araU is converted into BV-araU monophosphate by cellular TK, and the inhibition of TS activity by BV-araU monophosphate in the YSR strain-infected cells results in the suppression of viral replication.     

Establishment of a human anaplastic thyroid cancer cell line secreting granulocyte colony-stimulating factor in response to cytokines

Summary A human anaplastic thyroid cancer cell line K-119, derived from a 77-yr-old woman who had developed marked neutrophilia and underwent surgery for anaplastic thyroid cancer, has been established. The spindlelike and polygonal cells in shape are stably proliferating since the beginning of its culture 2 yr ago. The cells grow rapidly and the population doubling time is 26 h. The chromosomes show many abnormalities and many marker chromosomes have been observed. Heterotransplantation of the cells into nude mice has resulted in the formation of tumors that are histologically interpreted as anaplastic cancer. The most noteworthy characteristics of the cell line are the many Ki-67-positive cells (86.3%) and that the cell line spontaneously secretes granulocyte colony-stimulating factor (G-CSF) and releases increased amounts of G-CSF in response to the stimulation of tumor necrosis factor, interleukin 1α, and interleukin 1β. The conditioned medium obtained from K-119 cells contains an autocrine factor stimulating the proliferation of themselves.