[A simultaneous determination of evodiamine and rutaecarpine in oriental pharmaceutical decoctions containing Evodia fruit by ion-pair high-performance liquid chromatography]

A simple and precise method was established for the simultaneous determination of evodiamine and rutaecarpine in oriental pharmaceutical decoctions containing Evodia Fruit using high-performance liquid chromatography with sodium dodecyl sulfate (SDS) as an ion-pair reagent. Evodiamine and rutaecarpine were eluted within 60 min without interference from co-existing components using an ODS column and a mixture of water-methanol-acetonitrile-SDS-phosphoric acid (600:330:70:5:0.01, v/v/v/w/v, pH 5.0) as a mobile phase.

Application of a dicistronic mRNA expression vector to antisense RNA expression in mammalian cells

One important role of antisense RNA expression in mammalian cell biology is to partially suppress the functions of target genes of which the functions are unknown but which are indispensable for host cell growth. Therefore, we applied a dicistronic mRNA expression vector to express antisense p53 RNA in mouse fibrosarcoma MethA cells. We also established several clones in which the p53 gene functions were partially suppressed by the introduced antisense RNA. Compared with the control MethA clones, the contents of p53 protein in those expressing the antisense RNA were about halved, and their growth rates were remarkably decreased. These results proved that an antisense RNA in a dicistronic mRNA construct decreases the cellular content of a targeted gene product and that clones harboring the dicistronic mRNA construct can be established in which expression levels of the introduced antisense RNA are controlled by the stringency of drug selection.

Effects of 13-hydroxy SM5887 in combination with other anticancer agents on human tumor cell lines

A new anthracycline derivative, SM5887, in combination with commonly used anticancer agents was evaluated against T-cell leukemia MOLT-3 and human osteosarcoma MG-63 cell lines in culture. MOLT-3 and MG-63 cells were incubated with various concentrations of 13-hydroxy SM5887 (SM5887-OH, the active metabolite of SM5887) and other drugs for 3 and 4 days, respectively. Cell growth inhibition was determined by MTT assay. The antitumor effects of the drug combinations at 80% inhibitory concentration (IC80) were analyzed by the isobologram of Steel and Peckham. In MOLT-3 cells, SM5887-OH had additive effects with bleomycin, etoposide, doxorubicin, cisplatin, mitomycin-C, 4-hydroperoxy ifosfamide, 5-fluorouracil, cytarabine, and vincristine, whereas it had mainly protective (marked antagonistic) effects with methotrexate. In MG-63 cells, SM5887-OH had additive effects with bleomycin, etoposide, doxorubicin, cisplatin, mitomycin-C, 4-hydroperoxy ifosfamide; mainly subadditive (mild antagonistic) effects with 5-fluorouracil and cytarabine; and mainly protective (marked antagonistic) effects with vincristine and methotrexate. These findings suggest that SM5887 is suitable for simultaneous administration with bleomycin, etoposide, doxorubicin, cisplatin, mitomycin-C, or ifosfamide and not suitable for simultaneous administration with methotrexate. The effects of SM5887 in combination with 5-fluorouracil, cytarabine or vincristine may be variable, depending on cell lines. To find optimal combinations, further in vitro and in vivo studies of antitumor activity and toxicity appear to be warranted.

Prostaglandin E2 at priming of naive CD4+ T cells inhibits acquisition of ability to produce IFN-gamma and IL-2, but not IL-4 and IL-5

We investigated the effect of prostaglandin E2 on the acquisition of cytokine-producing ability by naive CD4+ T cells in human cord blood. Naive CD4+ T cells were stimulated for 3 days with mouse monoclonal anti-CD3 Ab, then washed and expanded in IL-2-containing medium for 3 more days. These activated T cells produced IL-2, IL-4, IL-5, and IFN-gamma upon stimulation with PMA and ionomycin. PGE2 added at priming of naive T cells inhibited the production of IL-2 and IFN-gamma, but not of IL-4 and IL-5, in a dose-dependent manner. This change in the cytokine production profile induced by PGE2 was maintained in T cells restimulated with anti-CD3 in the absence of PGE2, expanded by IL-2, and stimulated with PMA and ionomycin. The mRNA expression of IFN-gamma and IL-2, but not that of IL-4, was also decreased in these cells. Forskolin and dibutyryl cAMP had a similar effect. PGE2 must exist at an early stage of T cell activation to inhibit priming for IL-2 and IFN-gamma production. PGE2 also showed this effect, even in the presence of exogenous IFN-gamma, at the primary stimulation. These results indicate that PGE2 inhibits the acquisition of the ability to produce IL-2 and IFN-gamma by acting directly on naive T cells. Our results suggest that PGE2 plays a role in facilitating the development of the Th2-type cytokine production profile.

Prostaglandin E2 at priming of naive CD4+ T cells inhibits acquisition of ability to produce IFN-gamma and IL-2, but not IL-4 and IL-5

We investigated the effect of prostaglandin E2 on the acquisition of cytokine-producing ability by naive CD4+ T cells in human cord blood. Naive CD4+ T cells were stimulated for 3 days with mouse monoclonal anti-CD3 Ab, then washed and expanded in IL-2-containing medium for 3 more days. These activated T cells produced IL-2, IL-4, IL-5, and IFN-gamma upon stimulation with PMA and ionomycin. PGE2 added at priming of naive T cells inhibited the production of IL-2 and IFN-gamma, but not of IL-4 and IL-5, in a dose-dependent manner. This change in the cytokine production profile induced by PGE2 was maintained in T cells restimulated with anti-CD3 in the absence of PGE2, expanded by IL-2, and stimulated with PMA and ionomycin. The mRNA expression of IFN-gamma and IL-2, but not that of IL-4, was also decreased in these cells. Forskolin and dibutyryl cAMP had a similar effect. PGE2 must exist at an early stage of T cell activation to inhibit priming for IL-2 and IFN-gamma production. PGE2 also showed this effect, even in the presence of exogenous IFN-gamma, at the primary stimulation. These results indicate that PGE2 inhibits the acquisition of the ability to produce IL-2 and IFN-gamma by acting directly on naive T cells. Our results suggest that PGE2 plays a role in facilitating the development of the Th2-type cytokine production profile.

Suppression of age-related changes in mouse hippocampal CA3 nerve cells by a free radical scavenger

This study was designed to evaluate the relationship between oxygen free radicals and age-related morphological changes in hippocampal nerve cells using K-7259 (N,N' bis[4-(3,4,5-trimethoxyphenyl)butyl] homopiperazine dihydrochloride), a known neuro-protective agent. A chemiluminescence assay has shown that this agent is a potent free radical scavenger with an IC50 of 1.6 x 10(-5)M. Mice fed diets containing 10, 20, 40 mg/kg/day of K-7259, for periods ranging from 25 to 40 or 50 weeks of age were used as test groups, and 10-, 20-, 30-, 40-, and 50-week-old mice fed a standard diet were used as controls. We measured the number and area of pyramidal nerve cells within a defined frame in the hippocampal CA3 field using an image analyzer and the density of nerve cells by the disector method. These values decreased gradually in controls as expected, and the number and area yielded a significant difference between control mice at the ages of 10 and 30 weeks. As compared with the corresponding controls, all test groups had greater cell numbers (statistical significance at 40 weeks in the 40 mg/kg/day group) and density, while cell areas were greater in all but a 10 mg/kg/day group (statistical significance at 50 weeks). In summary, the free radical scavenger K-7259 forestalled an age-related decrease in the number and size of hippocampal CA3 nerve cells, thus suggesting that free radicals play an important role in the cellular morphological changes which appear with age.

Neural activity of chorda tympani mechanosensitive fibers during licking behavior in rats

The chorda tympani nerve, supplying the anterior two-thirds of the tongue, contains gustatory and mechanosensitive afferent fibers. We have analyzed discharge patterns in rats of various fibers recorded from dissected nerve filaments during licking behavior of which 4 were taste-sensitive and 12 mechanosensitive. The incidence of these two types were estimated electrophysiologically under anesthesia and their conduction velocity measured. Recordings in freely moving animals showed that the mechanosensitive fibers innervating the dorsal part of the tongue gave two burst discharges per lick, suggesting that contact of the tongue with the upper incisors and/or lip occurred during tongue protrusion and retraction. The fibers from the tip of the tongue showed one burst discharge per lick, which was the response to contact with a drinking spout. No rhythmical discharges synchronized with lick signals were observed in the fibers from the lateral part of the tongue or the taste-sensitive fibers. Such mechanoreceptor discharges were difficult to detect in recordings from the whole chorda tympani nerve. This masking of responses was due mainly to activation of a small number of mechanosensitive fibers by licking-induced mechanical stimulation. The lubricating action of saliva also decreased mechanoreceptor sensitivity. Despite their small number, the mechanosensitive fibers had axons with faster conduction velocities (larger diameter) than the taste-sensitive fibers. This was probably the reason why dissected nerve bundles more frequently showed mechanical than taste responses in conscious rats.

Temperature-sensitive mutation of DNA polymerase alpha induces growth-suppressive phenotypes involving retinoblastoma protein and cyclin D1

Temperature-sensitive (ts) cell cycle mutant mouse cell, tsFT20, is deficient in DNA polymerase alpha activity to initiate DNA replication at replicon origins. Here, we analyzed phenotypes concerning growth control genes in the arrested tsFT20 cells. Analysis of cyclins showed that expression levels of cyclin D1, which is essential for G1/S transition, remarkably decreased in the mutant cells after temperature up-shift. Further we examined phosphorylation states of retinoblastoma protein (pRB) in the cells. Though the tsFT20 cells arrested in G1/S-S phase at nonpermissive temperature (Eki et al., (1990) J. Biol. Chem. 265 26-33), a large proportion of pRB was found as an underphosphorylated growth-suppressive form in the arrested cells. In revertant cell lines of tsFT20, pRB was not underphosphorylated even at nonpermissive temperature. The pRB underphosphorylation occurred later than the decrease of mRNA levels of cyclin D1, thus the underphosphorylation may be caused by the decrease in amount of cyclin D1 protein. These results indicated that the mutational inactivation of DNA polymerase alpha evokes phenotypes in which the inhibitory machinery of G1/S transition has been turned on.

Generation of novel rapamycin structures by microbial manipulations

A new rapamycin producing culture was isolated and designated as Actinoplanes sp. N902-109. The addition of a cytochrome P-450 inhibitor and precursor feeding using this culture, and biotransformation approaches generated new rapamycin analogs with modifications at C-4, C-9, C-16, C-27, C-28 and/or C-39. The immunosuppressive activity of the resulting analogs was established in the mixed lymphocyte reaction assay.

[Whole mouth gustatory test (Part 2)--Effect of aging, gender and smoking on the taste threshold]

The whole mouth test method was employed for examining changes in gustatory senses due to aging. Participants were 314 male and 356 female healthy volunteers not complaining of taste disorders. Simultaneously, the effects of smoking were examined, comparing 71 male smokers to 142 male non-smokers, ranging from 20 to more than 60 years of age. A multiple comparison procedure (Tukey-Kramer) was applied to age groups, revealing a significant increase in the threshold with age; high threshold values were observed in the "70s and older" group in comparison to the younger group for all tastes other than the sweet taste. Concerning the differences between males and females, the gustatory thresholds of males were found to be higher than those of females for some in the "20s and older" group and for all tastes other than the sweet taste, whereas the thresholds of males were lower than those of females for all taste qualities in the late teen group. As to male subjects in whom the effects of smoking could be studied, smokers in their 20s demonstrated a slight rise in the threshold only for the bitter taste.

Physical interaction with monocytes rescues human mature CD4+ T-cell lines from anti-CD3-induced apoptosis

Crosslinking of the TcR-CD3 complex with immobilized anti-CD3 antibodies without sufficient co-stimulation induced cell death in human mature CD4+ T-cell lines. In these T cells, DNA fragmentation and morphological characteristics of apoptosis were seen. The anti-CD3-induced apoptosis was inhibited by co-culture with monocytes. The rescue signal provided by monocytes does not need to be present simultaneously with signals mediated by anti-CD3. When T cells were precultured with monocytes for 24 h before anti-CD3 stimulation and then the monocytes were removed from the culture, anti-CD3-induced T-cell apoptosis was also inhibited. To determine whether the monocyte-derived rescue signals were transduced by soluble factors or by direct cell-to-cell interaction with monocytes, we precultured T cells with monocytes separated by a micropore membrane which prevented T cell-monocyte physical interaction but not the diffusion of secreted molecules. In this system, rescue signals could not reach the T cells. To further assess the importance of physical interaction, we precultured T cells with fixed monocytes. T cells could not be rescued from apoptosis under these experimental conditions, either. The results considered collectively suggest that sufficient physical interaction with viable monocytes is important for the rescue of anti-CD3-induced apoptosis of CD4+ T cells.

Antinuclear antibodies in healthy aging people: a prospective study

In order to evaluate the expression of antinuclear antibodies (ANA) in normal elderly individuals over time and clinical significance, a cross-sectional ANA testing in healthy Japanese was performed, followed by annual evaluations of ANA positive aged (> or = 65 years) and a control group. ANA was more prevalent in the aged (11.4% vs. 3.8%) and most were persistent after 4 years. Anti-ssDNA and anti-histone antibodies were increased in aged ANA positive as compared to ANA negative controls. Except for a history of spontaneous abortion, there was no differences in clinical findings. HLA DRB1*0901 and the DQB1*0602 + 0302 + 0303 set of alleles were increased in ANA positive. Therefore, ANA in the aged were persistent, apparently directed toward chromatin elements, and shared MHC associations with autoimmune diseases. Longer follow-up may be necessary to improve the evaluation of clinical significance of ANA in the aged.

CJ-12,371 and CJ-12,372, two novel DNA gyrase inhibitors. Fermentation,isolation, structural elucidation and biological activities

A fermentation broth of an unidentified fungus (N983-46) was found to produce DNA gyrase inhibitors, CJ-12,371 (1) and CJ-12,372 (2). Following isolation by solvent extraction and silica gel and ODS (reverse phase) chromatographies, the structures were determined to be novel spiro-ketal compounds with S-configuration at position C-1. CJ-12,371 and CJ-12,372 inhibit both DNA supercoiling and relaxation mediated by Escherichia coli DNA gyrase. The interaction of these compounds with DNA gyrase appears to be novel in that the compounds inhibit supercoiling and relaxation without blocking religation; thus, no cleavage intermediate of double strand DNA is observed. Both compounds have antibacterial activity against several species of pathogenic Gram-positive bacteria, with MICs between 25 and 100 micrograms/ml. These results suggest that the antibacterial potency of CJ-12,371 and CJ-12,372 is attributed to the inhibition of DNA gyrase. However, the compounds did not inhibit DNA gyrase selectively, as they also inhibited eukaryotic topoisomerase II-mediated relaxation. Semi-synthetic modifications to the dihydroxy motif in CJ-12,371 altered both gyrase- and topoisomerase II-inhibitory activities, but did not enhance selectivity.

Selective induction of interleukin-4- and interferon-y-producing T cells from cord blood naive T cells. Effects of costimulatory signaling through CD28

We investigated the effect of costimulation through CD28 and CD11a on the differentiation of human naive CD4+ T cells with restricted cytokine production profiles. Interleukin (IL)-4 and interferon-gamma (IFN-gamma) were measured by ELISA and IL-2 was detected by a bioassay. Naive CD4+ T cells proliferated and produced IL-2 upon cross-linking of CD3, and costimulation through CD28 enhanced IL-2 production. After repeated stimulation, CD4+ T cells which were stimulated in the absence of costimulation through CD28 lost their ability to secrete IL-2 and started secreting IL-4 and IFN-gamma. Instead in the presence of costimulation through CD28, they secreted IL-2, IL-4 and IFN-gamma. Blocking of endogenous IL-4 activity with anti-IL-4 Ab suppressed the IL-4 secretion and proliferation of T cells.

Transient expression assay for antisense RNAs using episomal replication of plasmids: effective reduction of retinoblastoma gene (Rb-1) product by its antisense RNA complementary to 3'-untranslated region

We have developed a transient expression assay for selection of effective antisense RNAs using episomal replication of plasmids in COS-7 cells, an African green monkey kidney-derived cell line expressing SV40 large T antigen. The transient expression assay was enabled by a liposome-mediated DNA transfection method, by which about 70% of the cells were reproducibly transfected with exogenous DNAs. Plasmids expressing antisense RNAs for the retinoblastoma gene (Rb-1) mRNA and harboring SV40 ori were constructed and introduced into COS-7 cells to examine their inhibitory effect on the accumulation of endogenous Rb protein (pRb). Only the antisense RNA complementary to the 3'-untranslated region (UTR) in Rb-1 mRNA was expressed stably at high levels for 3 days after the transfection. This antisense RNA reduced by 73% the content of endogenous pRb 70 h after transfection. A similar inhibition was detected in mouse mammary carcinoma cells (FM3A) that were stably transfected with the antisense RNA expressing vector directed to 3'UTR. In contrast, no obvious change in pRb was observed with antisense RNAs complementary to the coding region of Rb-1 mRNA. The cellular content of these antisense RNAs was lowered by degradation; thus these RNAs did not affect the levels of pRb in COS-7 and FM3A cells. These results, taken together, suggest that the expression levels and the stability of antisense RNAs are involved in their repressive activity, and our transient expression assay provides a rapid and easy system for evaluation of ectopic antisense RNA activity in COS-7 cells.

[Whole mouth gustatory test (Part 1)--basic considerations and principal component analysis]

The whole mouth method gustatory test is a simple gustatory test. It can be applied easily, and can be used to assess overall taste which a subject is supposed to be feeling. In the present study, a new series of taste solutions for the use in the whole mouth gustatory test was prepared. In order to determine the normal range of gustation and relationships between each taste solution, gustatory threshold tests were conducted on 123 healthy volunteers (17-22 years old). The series of taste solutions represented 4 tastes, i.e., sweet, salty, sour, and bitter, and was prepared using sucrose, salt, tartaric acid and quinine, respectively. Recognition thresholds measured for each taste solution yielded normal ranges i.e., 0.0165 mol/l for the sweet solution, 0.0316 mol/l for the salty solution, 0.000734 mol/l for the sour solution, and 0.0000203 mol/l for the bitter solution which were almost the same as those published. The average thresholds obtained for all solutions were at almost always at the middle concentration level, i.e., level 6. Thus, this method can serve as a standard method of performing the whole mouth taste test. Principal component analysis of the thresholds obtained revealed that the primary component mainly demonstrated taste detection function, and that it could more or less be represented by the simple sum of each detection threshold. The analysis also showed that approximately 90% of taste threshold variation is explained by the 4 principal components. These findings provide further evidence that these four tastes comprise the basic elements of taste.

Frequent p53 mutation in mouse tumors induced by repeated beta-irradiation

On examination of cDNA of the p53 gene in 65 murine tumors of the skin and bone produced by repeated exposure to a suprathreshold dose of 1-8 Gy of 90Sr-90Y beta-radiation per exposure, we found 20 cases of mutation: 11 minute deletions (loss of 1-24 bp), including two cases possibly due to aberrant splicing; three insertions of 4-8 bp; and six base-pair substitutions, including four at CpG sites, three being identical changes at codon 122 (a p53 hot spot). All but one of these mutations were confined to the central region of the p53 gene. From frameshifts created by deletions and insertions, the minimum size of the mutant p53 proteins found in these tumors was estimated to be 55% of the intact size. Cells of 17 of 19 tested tumors with p53 mutation were positive for immunostaining of p53 proteins accumulated in the nuclei and so were clearly different from nonneoplastic cells. Ha-ras mutation was absent in these tumors, indicating that repeated beta-irradiation created a cell-growth stimulating effect similar to that of ras mutation.

Oxygen uptake kinetics are determined by cardiac function at onset of exercise rather than peak exercise in patients with prior myocardial infarction

BACKGROUND

Resting cardiac function does not necessarily affect exercise capacity. However, to determine whether it affects early dynamics of oxygen uptake (VO2) during exercise, we measured VO2 during a constant work rate and during incremental exercise testing in patients with a history of myocardial infarction. VO2 kinetics and exercise capacity were compared between patients with relatively high left ventricular ejection fractions (LVEF > or = 35%, group 1) and those with lower ejection fractions (LVEF < 35%, group 2).

METHODS AND RESULTS

Forty patients with a history of prior myocardial infarction (age, 57 +/- 10 years) were monitored during 6 minutes of moderate constant work rate testing (40 +/- 8 W) and during symptom-limited incremental exercise testing with a cycle ergometer. VO2 was calculated from respired gas analysis on a breath-by-breath basis. Cardiac output determinations were made with a computerized cadmium telluride detector every 10 seconds during exercise. The VO2 time constant during constant work rate exercise was slower in group 2 (58.0 +/- 7.6 seconds) compared with group 1 (45.8 +/- 10.5 seconds, P = .0002), indicating slower kinetics in group 2. The time constant for the rise in cardiac output during exercise was also slower in patients with lower EFs (63.0 +/- 12.8 versus 50.0 +/- 12.2 seconds). However, there were no differences in exercise capacity parameters, such as the VO2 or cardiac output at peak exercise, obtained during incremental exercise testing among the two groups.

CONCLUSIONS

The prolonged time constant of VO2, which is primarily determined during early parts of exercise, reflects delayed cardiac output response in patients with severely impaired LV function. The time constant of VO2 during submaximal constant work rate exercise can be used as a sensitive and discriminant measure of impaired cardiac reserve in these patients.

A new method for continuous measurement of regional cerebral blood flow using laser Doppler flowmetry in a conscious rat

We have developed a new system to continuously measure regional cerebral blood flow (rCBF) in the cortex of a conscious animal. For this purpose, we used rats and laser Doppler flowmetry. Under pentobarbital anesthesia, the animal's skull was opened making a small square hole 3 mm x 3 mm in size. A transparent acrylic plate was placed over the hole in the skull. A polyethylene cannula (inner diameter 1.0 mm, length 5.0 mm) was fixed on the plate as a guide for the laser Doppler flowmeter (LDF) probe (outer diameter 1.0 mm, length 5.5 mm). Both the plate and guide cannula were fixed to the skull by dental cement. Every day for the following two weeks after surgery, the conscious animal was placed in a hammock for recording rCBF. A LDF probe was freely attachable to the plate above the cortex via the guide cannula during measurement of rCBF. The rats were kept in a hammock with their legs firmly touching the floor during measurement of rCBF. It was possible to measure rCBF every day for about two weeks, and rCBF responded consistently to inhalation of 7% CO2 when the responses were expressed as percentages of the prestimulus control rCBF values. This system is recommended for the continuous measurement of rCBF in a conscious animal.

[Ritodrine induced pulmonary edema after caesarean section for a triplet pregnancy]

Selective beta-sympathomimetic drugs are frequently used for tocolysis. But, since these drugs exhibit some beta-1 activity as well, they may bring about pulmonary edema, myocardial ischemia, cardiac arrhythmia and others as side effects. A 29 year-old female with a triplet pregnancy had premature contraction at 26 weeks of gestation. High doses of IV ritodrine were given for tocolysis for 8 weeks until caesarean section. One hour after caesarean section at 35 weeks of gestation, she complained of dyspnea. Urinary output decreased and chest X-ray showed pulmonary edema. She was intubated and artificial ventilation with PEEP was performed in ICU. Echocardiogram showed left ventricular dilatation. ECG showed inverted T waves on all leads. We diagnosed her as suffering from acute heart failure, pulmonary edema and acute renal failure. Hemodialysis was performed for 6 hrs but PCWP was still 18 mmHg. So CVVH was added to hemodialysis. Five hrs after the start of CVVH, her symptoms gradually started to subside. Total fluid removal was 5.8 l over 16 hrs. Three days after admission she was extubated and five days later returned to her ward. We concluded that pulmonary edema, heart failure and renal failure were induced by the long-term high dose medication of ritodrine, resulting in volume overload and myocardial dysfunction.