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In this paper, we report progress in the development of a detector for photons in the terahertz region consisting of a lateral quantum dot (QD), defined in a semiconductor heterostructure by mesa patterning and three negatively biased metallic gates, and a single-electron transistor (SET) on top of the mesa and, hence, capacitively coupled to the QD. We study the behavior of the QD as a function of the potential applied to the gates using the SET as a sensitive charge detector and identify the bias region of the device, where it is sensitive to incident terahertz radiation. The QD converts incident photons into charge excitations, which can be detected by the SET, resulting in a signal of the order 10 8 electrons for each absorbed photon. Based on the dark count rate and an estimate of the quantum efficiency, the detector should enable low-power measurements in the terahertz region with noise-equivalent power ~10-19 W/Hz1/2 exceeding the sensitivity of commercially available bolometers by two orders of magnitude

Sorption and diffusion of NaCl in Japanese radish have been studied. The sorption isotherm was obtained at 98 degrees C by the conventional method. The concentration profile by the 1-dimensional diffusion of NaCl in Japanese radish from the 3.0% solution was measured at 98 degrees C with the FRITRUC method involving a foodstuff rod in a thin rubber casing. Fick's diffusion coefficient, D, calculated therefrom showed a threefold variation with a maximum. This variation was quantitatively interpreted by applying a dual-mode sorption and diffusion theory under an assumption that the rate determining step of the diffusion is that in the cell wall. Two thermodynamic diffusion coefficients, D(T)(p) and D(T)(L), where p and L are the species of NaCl sorbed by partition and Langmuir modes, respectively, a parameter, alpha, derived from the local equilibrium relations between the p and L species, and S, the concentration of the Langmuir adsorption site in the cell wall of the radish, were estimated. D(T)(p) was found to be smaller than D(T)(L). As an explanation of the larger D(T)(L), we invoked the higher hydration state of the adsorption site of the L species, being ascribed to residual anionic pectin in the radish than the local environment of the p species. The sorption isotherm showed a convex upward deviation from the linear relation. By using the parameters for the local equilibrium and some assumed parameters, the isotherm was found to be explainable. We suggest possible applications of the present method and interpretation to the diffusion study on the cooking systems comprising varieties of seasoning components and foodstuffs.

S. FUJIWARA, Y. SETO, A. KIMURA AND H. HASHIBA. 2001. Aims: The objectives of this study are to investigate the fate of a streptomycin–rifampicin-resistant variant of Bifidobacterium longum SBT2928 (BL2928SR) and the influence of its oral administration on the composition and metabolism of the intestinal microflora. Methods and Results: Intestinal passage of BL2928SR was monitored by a combination of selection with antibiotics and identification by a randomly amplified polymorphic DNA (RAPD)–PCR method. Intestinal microflora was analysed by the method developed by Mitsuoka et al. (1965, 1974). Long-term survival of orally administered BL2928SR in the human intestine was confirmed. BL2928SR ingestion specifically lowered faecal populations of Enterobacteriaceae and clostridia, including lecithinase-positive Clostridium spp. Conclusions: BL2928SR and its parent strain, BL2928, are considered to be appropriate candidates for probiotics. Significance and Impact of the Study: It is clarified that BL2928SR has the ability for long-term survival in the human gastrointestinal tract, and alters the composition and metabolism of the intestinal microflora.

A novel protein (BIF) which shows inhibitory activity on the binding of enterotoxigenic Escherichia coli Pb176 (ETEC with colonization factor antigen (CFA) II, which consists of coli surface-associated antigens CS1 and CS3) to gangliotetraosylceramide (asialo GM1 or GA1) was isolated from the culture supernatant fluid of Bifidobacterium longum SBT2928 (BL2928) at its stationary phase. The homogeneity of the final preparation of BIF was demonstrated by SDS-PAGE, polyacrylamide gel electrofocusing and N-terminal amino acid sequencing. The BIF was characterized as (i) a protein with an M(r) of approximately 104 kDa when chromatographed on a gel filtration column, and 52 kDa when separated on SDS-PAGE, and (ii) having an isoelectric point of 5.9. No change in size was produced by thiol reduction. These results suggest that BIF is a homodimer consisting of identical 52 kDa monomers. The purified BIF at the concentration of 25 micrograms protein ml-1 caused a 50% reduction in binding of the ETEC strain to GA1.

The formation of 1 μm-diameter quantum dot (QD), defined by mesa patterning and metal gates in a GaAs/AlGaAs heterostructure, is studied using a capacitively coupled aluminium single-electron transistor (SET). The SET senses the charge of the QD at different gate potentials and can identify stable and metastable states of the QD. An electrostatic model gives a good description of the stable states, leaving, however, some unanswered questions concerning the metastable states. The application of the device for the sensitive detection of terahertz radiation is discussed.

The study was carried out to examine the effect of whey from bovine skim milk fermented with bifidobacteria and lactic acid bacteria on plasma cholesterol and antioxidant enzymes in rats. Rats were maintained for 6 wks on a purified diet (reference diet) and on the purified diet supplemented milk whey or whey from cultured skim milk with Bifidobacterium longum (B. longum), Lactobacillus acidophilus (L. acidophilus) or Streptococcus salivarius subsp. thermophilus (S. thermophilus) . Diets containing the product with S. thermophilus resulted in the lowest concentration of plasma cholesterol. The activity of superoxide dismutase (SOD) in red blood cells (RBC) and the activity of catalase in liver were elevated on cultured product-diets compared with the reference diet; in addition, the activity of glutathione peroxidase (GSHPx) in RBC was higher on the L. acidophilus diet compared with the reference diet. Although there were no significant differences in the concentrations of thiobarbituric acid-reactive substances and α-tocopherol in plasma, plasma d B. longum - and L. acidophilus -diets were resistant to the oxidative stress induced by a transition metal ion when compared with those from rats fed on the reference diet. The non-fermented whey diet was not as effective in lowering plasma cholesterol and in increasing antioxidant enzymes as were the fermentation product diets. These results therefore suggest that wheys from cultured milk may exert spesific effects on hypercholesterolemia and oxidative stress.

A highly sensitive detector of submillimeter wavelength radiation is reported. The detector consists of a semiconductor quantum dot (QD) and a metallic single-electron transistor (SET). The SET detects change in the potential distribution induced by photon absorption within the QD. We have fabricated and studied this detector at wavelengths longer than 200μm. High sensitivity, ∼10−20W∕Hz in terms of noise equivalent power, is found. Further optimization of the detector design is suggested.

P(論文), http://www.tsc-05.ac.jp/pdf_library/2015.pdf

We present an experimental study of a large quantum dot (QD) capacitively coupled to an aluminum single electron transistor (SET) and irradiated with terahertz radiation from a blackbody source. The SET is used as a noninvasive electrometer sensitive to a single-charge fluctuation on the QD. Qualitatively different regimes of QD confinement have been identified from the SET response. We demonstrate that the state of a nearly isolated QD can potentially be used for counting individual terahertz photons. © 2006 The American Physical Society.

Aims: To investigate the fate of a streptomycin–rifampicin-resistant variant of Lactobacillus gasseri SBT2055 (LG2055SR) and the influence of its oral administration on the composition and metabolism of the intestinal microflora. Methods and Results: Intestinal passage of LG2055SR was monitored by a combination of selection with antibiotics and identification by a randomly amplified polymorphic DNA (RAPD)-PCR method. Composition of intestinal microflora was analysed by the method developed by Mitsuoka et al. (1965, 1974). Establishment of orally-administered LG2055SR in the human intestine was confirmed in this study. LG2055SR ingestion specifically lowered faecal populations of Staphylococcus and faecal contents of p-cresol. Conclusions: LG2055SR and its parent strain, LG2055, are considered to be appropriate candidates for probiotics. Significance and Impact of the Study: It is clarified that LG2055SR has the ability to establish in the human gastrointestinal tract and alters the composition and metabolism of the intestinal microflora and physical characteristics of faeces.

Serum antibodies against five types of phospholipids were measured by enzyme-linked immunosorbent assay (ELISA) in 55 patients with sarcoidosis. In 21 cases (38%), either IgG antibodies or IgM antibodies were detected. These antibodies were thought to mainly be infective type. This positive rate was significantly higher than that (7%) of the control group (70 cases) (p0.01). As to the immunoglobulin classes, 5 cases had IgG antibodies only, 11 cases had IgM antibodies only, and 5 cases had both IgG and IgM antibodies. No correlation was observed between the occurrence of anti-phospholipid antibodies (APL-Ab) and disease activity of sarcoidosis. Significant correlations were found between the occurrence of APL-Ab and skin lesions, many extrathoracic organ lesions and the persistence of abnormal chest X-ray findings for over 2 years and 5 years. From these data, it is suggested that the presence of APL-Ab is associated with prolonged disease activity of sarcoidosis.

We investigated the transport properties of an S-Sm-S junction with a two-dimensional electron gas (2DEG) in an In0.52Al0.48As/In0.7Ga0.3As heterostructure when exposed to light from infrared laser diodes. When the sample was illuminated with λ = 1.3 μm, we observed a reduction in the junction resistance as well as an enhancement of Andreev reflection. In contrast, we observed negative photoconductivity owing to a reduction in the number of electrons in the 2DEG when it was exposed to 1.3 μm light, by employing both Shubnikov-de Haas and Hall-effect measurements. These experimental results indicate that the improvement in the superconducting properties does not originate from the photo-induced carriers in the 2DEG but from the increase in the Andreev reflection probability at the S/Sm interface caused by lowering the interface barrier.

Interleukin-2 receptor expression (IL-2R) on monocytes and alveolar macrophages (AM) was determined in patients with sarcoidosis and pulmonary tuberculosis. In sarcoidosis and tuberculosis, IL-2R on monocytes was detectable, while it was undetectable in healthy controls. IL-2R on AM in sarcoidosis and tuberculosis was significantly increased as compared to healthy controls. IFN-gamma, which has been shown to be increased in sarcoidosis and tuberculosis as compared to healthy controls, induced IL-2R on monocytes in healthy controls, suggesting that IFN-gamma is at least in part responsible for the induction or enhancement of IL-2R on monocytes or AM in sarcoidosis and tuberculosis. Phorbol myristate acetate which is known to be protein kinase C (PKC) activator induced IL-2R on monocytes, and PKC inhibitor, H7, inhibited IFN-gamma-induced IL-2R on monocytes in healthy controls. Calcium ionophore, A23187, induced IL-2R on monocytes and calmodulin antagonist, W7, inhibited IFN-gamma-induced IL-2R on monocytes. Based on these results, it seems that not only the PKC pathway but also the calcium-calmodulin pathway is involved in IFN-gamma-induced IL-2R.

Serum levels of soluble IL-2 receptors (sIL-2R) by an ELISA method in 28 patients with sarcoidosis and 16 healthy controls were studied, and the source of sIL-2R was further examined. sIL-2R in serum was significantly higher in sarcoidosis than in controls. In sarcoidosis sIL-2R in serum significantly correlated with serum ACE level, and was significantly higher in stage II or III patients than in stage O patients. sIL-2R in supernatants of cultured monocytes (Mo) and alveolar macrophages (AM) was significantly higher in sarcoidosis than in controls. sIL-2R in supernatants of cultured T lymphocytes obtained from peripheral blood or BALF was barely detectable in sarcoidosis, while it was undetectable in controls. Furthermore, sIL-2R in serum was significantly correlated with sIL-2R in supernatants of cultured Mo and AM. These results indicate that sIL-2R in serum is an useful index of the disease activity of sarcoidosis, and may be mainly derived from IL-2R on Mo and AM.

One approach for identifying chromosomes which carry putative tumor-suppressor genes is the introduction of specific chromosomes into the tumor cells of interest. We examined the ability of human chromosomes derived from normal fibroblasts to suppress or modulate tumorigenicity in nude mice and the in vitro properties of HT1080, a human fibrosarcoma cell line. We first isolated mouse A9 cells containing a single human chromosome (1, 2, 7, 11, or 12) integrated with pSV2neo plasmid DNA. Following fusion of microcells from these A9 cells with the HT1080 cells, clones that were resistant to G418 were isolated and karyotypically analysed. Three of 4 microcell-hybrids with an introduced chromosome 1 were non-tumorigenic (#1-7, -8 and -13), whereas the parental HT1080 cells were highly tumorigenic. The other microcell-hybrid clone (#1-1) formed tumors, the cells of which had lost one copy of chromosome 1. Two clones from the #1-1 cells were isolated; one contained an extra copy of chromosome 1, and the other one did not. The former was non-tumorigenic and the latter was tumorigenic. The introduction of chromosome 11 also suppressed the tumorigenicity of HT1080 cells, while the introduction of other chromosomes, i.e., 2, 7, or 12, had minimal or no effect on the tumorigenicity of these cells. Cells from tumors formed by microcell-hybrids with the introduction of chromosome 2, 7, or 12 still contained the introduced chromosome. Interestingly, only the microcell-hybrids with an introduced chromosome 1 had an alteration in cellular morphology and modulation of in vitro transformed properties, i.e., cell-growth and saturation density in a medium containing 10% calf serum and cell-growth in soft-agar. Thus, the results indicate the presence of putative tumor-suppressor genes for HT1080 cells on chromosomes 1 and 11, and further suggest that the genes on these chromosomes control different neoplastic phenotypes.

A 28 year-old male was admitted to our hospital with persistent cough and high fever. He was diagnosed to have miliary tuberculosis by the transbronchial lung biopsy specimen and tuberculous choroidal lesions in the ocular fundus. Antituberculosis therapy was immediately started. In spite of the fact that the bacilli were sensitive to the antituberculosis drugs used and he had no other complications, high fever persisted and lasted for more than 2 months. When tuberculosis is suspected, and antituberculosis treatment is tried to observe its clinical response, the presence of similar cases mentioned above should be taken into consideration.

We report progress in developing a sensitive detector for terahertz radiation, based on a semiconductor quantum dot (QD) capacitively coupled to a metallic single electron transistor (SET). A charge polarization of the QD induced by the absorption of individual photons is detected by the voltage-biased SET. We investigate the sensitivity of the detector to broadband radiation, over a range of QD barrier heights, and find that there is a measurable photo-signal over wide range of gate voltages defining the QD. This is an improvement on previous designs of terahertz detector based on the QD/SET principle, and makes the new detector a candidate for use in an imaging device.

Propylene oxidation on Bi- and Fe-doped molybdate (MMoO4)-based catalysts proceeds to acrylic acid via acrolein utilizing their bifunctional properties. The first step of acrolein formation occurs on the surface of Bi molybdate; acrolein is subsequently oxidized to acryclic acid on the acid sites. The acidic site is related to the coordinatively unsaturated Mo ion in the surface Mo oxide coordinated with MMoO4.

Bacillus brevis 47 contains two cell wall proteins termed the outer wall protein (OWP) and middle wall protein (MWP), each of which forms hexagonal arrays in the cell wall. A 6-kilobase BglII-BclI fragment of B. brevis 47 DNA cloned into Bacillus subtilis with a derivative of pHW1 as a vector directed the synthesis of a polypeptide, with almost the same molecular weight as the authentic OWP, as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which was specifically recognized by the anti-OWP antibody. Nucleotide sequence analysis of the subfragment revealed that it contains two open reading frames in tandem. The upstream truncated open reading frame corresponds to the carboxy-terminal portion of the MWP, and the downstream open reading frame corresponds to the entire translational portion of the OWP. The latter encodes a secretory precursor of the OWP, consisting of a total of 1,004 amino acid residues with a signal peptide of 24 amino acid residues at its amino-terminal end. Futhermore, analysis of transcripts in B. brevis 47 suggests that the MWP and OWP genes, in that order, constitute a cotranscriptional unit and that the major promoter shared by the two genes is located upstream of the MWP gene.

The activation of protein kinase C and protein phosphorylation by tumor promoters were examined using quiescent cultures of BALB/3T3 and C3H/10T1/2 cells, because in these cells tumor promoters enhance chemically induced transformation and also induce DNA synthesis and ornithine decarboxylase. The cytosol and membrane fractions were partially purified, and the activity of protein kinase C was assayed. In quiescent cells, protein kinase C activity was found only in the cytosol fraction. Treatment with 100 ng of 12-O-tetradecanoylphorbol-13-acetate or teleocidin B per ml caused rapid translocation of protein kinase C from the cytosol to the membrane fraction. The activity in the cytosol disappeared almost completely after 15 min when the activity in the membrane reached a peak. The membrane activity gradually decreased to the control level after 6 h, while no activity reappeared in the cytosol within 6 h. Under these circumstances, a membrane protein with a molecular weight of 90,000 and pl of 4.0-4.4 (termed p90) was specifically phosphorylated, possibly by the activated protein kinase C, in both cell-free and intact-cell systems. On treatment of quiescent BALB/3T3 cells with 100 ng of 12-O-tetradecanoylphorbol-13-acetate, p90 phosphorylation increased 2-fold in 1 min, reaching a peak in 15 min of 3.4-fold the initial value. The phosphorylation of p90 increased with increase in the concentrations of 12-O-tetradecanoylphorbol-13-acetate between 0.1 and 10 ng/ml and reached a plateau at 10 ng/ml. p90 phosphorylation also occurred on exposure of the cells to non-phorbol ester tumor promoters (mezerein and teleocidin B) and growth factors, such as platelet-derived growth factor and fibroblast growth factor. p90 was not immunoprecipitated by antibody against the insulin receptor. Phosphorylation of p90 occurred at a serine residue. The present study suggests that activation of protein kinase C and phosphorylation of p90 by it are early events leading to tumor promotion.

The clinical effects of PC-904, a new semisynthetic penicillin, were studied in patients with biliary tract diseases, and the results were as follows: 1) PC-904 showed an average peak serum level of 40.7 +/- 11.6 microgram/ml 2 hours after an intravenous drip infusion of 1 g of the agent. The biliary level showed a peak value of 126.5 +/- 85.4 microgram/ml 2 hours to 3 hours after the infusion. 2) Isolated organisms from bile before the treatment were E. coli, Klebsiella, Proteus, Pseudomonas, Enterococcus and Bacteroides. MIC of PC-904 on 18 strains of isolated organisms was almost 6.25 microgram/ml or less. All isolated organisms except one strain of Klebsiella oxytoca disappeared after the treatment. 3) Six patients with cholelithiasis were medicated with PC-904 to prevent post-operative infections. The clinical effects were good in 4, poor in 1 and unknown in 1 case. 4) As to side effects no adverse reactions and allergic reactions were noted. Also no significant abnormalities of laboratory findings were observed.

Topical application of 1 alpha, 25-dihydroxyvitamin D3 [1 alpha, 25-(OH)2D3], an active form of vitamin D3, markedly inhibited induction of ornithine decarboxylase caused by 12-O-tetradecanoylphorbol-13-acetate (TPA) and teleocidin B in mouse skin. The degree of inhibition was dependent on the dose and time of application of 1 alpha, 25(OH)2D3. Application of 1 micrograms 1 alpha, 25(OH)2D3 within 30 min before or after treatment with 10 micrograms TPA caused about 72% inhibition of ODC induction at 4 hr. Similar degrees of inhibition were obtained with dose ratios of 1 alpha, 25(OH)2D3 to TPA of 1:3, 1:10, and 1:30. The dose required for 50% inhibition was 0.063 micrograms, or 0.15 nmol, which is about one-half that of retinoic acid, a known inhibitor of induction of ODC activity by TPA. 1 alpha, 25(OH)2D3 had a specific inhibitory effect, in which 100 times higher doses or more of other derivatives of vitamin D3, such as 1 alpha-hydroxyvitamin D3, 25-hydroxyvitamin D3, 24R,25-dihydroxyvitamin D3, and vitamin D3, were required to inhibit ODC induction by TPA. 1 alpha, 25(OH)2D3 did not inhibit epidermal hyperplasia induced by TPA.

1 alpha,25-Dihydroxyvitamin D3 [1 alpha,25(OH)2D3], a hormonally active form of vitamin D3, was found to inhibit the promotional phase of 7,12-dimethylbenz[a]anthracene-induced skin carcinogenesis in female Sencar mice. Topical application of 1 alpha,25-(OH)2D3 once a week at a dose of 1 micrograms or less, a tolerable dose from hypercalcemia, dose dependently inhibited tumor promotion by 12-O-tetradecanoylphorbol-13-acetate (TPA). When 1 micrograms of 1 alpha,25(OH)2D3 was applied 30 min before 5 micrograms of TPA, the times required for 50 and 100% tumor incidence were delayed about 2.5 and 7 weeks, respectively, and the number of tumors per mouse was decreased by 25-30%. This inhibitory effect was more pronounced when examined by a two-stage promotion protocol, in which a single application of 5 micrograms of TPA (Stage I) was followed by repeated applications of 5 micrograms of mezerein once a week for 19 weeks (Stage II). When 1 alpha,25(OH)2D3 at 1 micrograms was applied at Stage I + II or Stage II, tumor formation was markedly suppressed, resulting in decrease of about 70-80% in the incidence and 87-90% in the number of tumors per mouse. Application of 1 alpha,25(OH)2D3 at Stage I only did not inhibit tumor formation, indicating that 1 alpha,25(OH)2D3 specifically inhibited Stage II promotion. These results are in good agreement with the previous and present findings that 1 alpha,25(OH)2D3 inhibited induction of epidermal ornithine decarboxylase by TPA and mezerein. The possibility that 1 alpha,25(OH)2D3 suppressed tumor promotion by killing initiated cells rather than inhibiting promotion was ruled out by an experiment in which TPA was applied to the 1 alpha,25(OH)2D3 alone-treated animals.

The ability of normal human fibroblast-derived chromosomes to suppress tumorigenicity in nude mice and in vitro growth properties of various tumor cell lines was examined. Normal human chromosomes tagged with pSV2neo gene by DNA transfection were transferred to the following human tumor cell lines by microcell-fusion: SiHa (uterine cervical carcinoma), A204 (rhabdomyosarcoma), SK-NEP-1 (Wilms' tumor), HHUA (uterine endometrial carcinoma), SK-N-MC (neuroblastoma), YCR (renal cell carcinoma), HT1080 (fibrosarcoma), and CC1 (chorionic carcinoma). The results indicate the presence of a putative tumor-suppressor gene(s) in multiple chromosomes, and suggest that multiple genes may normally be involved in suppressing the transformed phenotypes at different stages in some tumors. Thus, the microcell transfer of chromosomes to specific tumor cell lines is a useful technique to demonstrate the presence of tumor-suppressor genes on individual chromosomes, and may also be useful in cloning of tumor-suppressor genes as well as elucidating their function in cell-growth and differentiation.

A small cryptic plasmid, pLJ1, was isolated from Lactobacillus helveticus subsp. jugurti and was cloned into Escherichia coli HB101 by using pBR329 as a vector. Plasmid pLJ1 was 3,292 base pairs long and had single restriction endonuclease sites for PvuII, KpnI, AvaII, Acci, HindIII, and EcoRI. In a maxicell system, pLJ1 produced a protein of about 41 kilodaltons.

We reported previously that 1 alpha,25-dihydroxyvitamin D3 [1 alpha,25(OH)2D3], a hormonally active form of vitamin D3, markedly enhanced methylcholanthrene-induced transformation of BALB 3T3 A31-1-1 cells. When the cells were treated with methylcholanthrene (1 microgram/ml) for 72 h and then with 1 alpha,25(OH)2D3 (5 ng/ml) for 2 wk, the transformation frequency was 1.95 +/- 0.73 (SD) foci/dish in 8 independent experiments, which was about 20 times that in cultures treated with methylcholanthrene only. Even at a physiological concentration in plasma, i.e., 0.05 ng/ml, 1 alpha,25(OH)2D3 enhanced the transformation frequency significantly (P less than 0.001). 1 alpha,25(OH)2D3 was not cytotoxic but slightly inhibited growth of the cells. Cells treated with 1 alpha,25(OH)2D3 were thin and became arranged in a meshwork with wide intercellular spaces. These morphological changes were reversible. 1 alpha,25(OH)2D3 induced DNA synthesis in quiescent BALB 3T3 cells dose and time dependently, but this effect was less than that of 12-O-tetradecanoylphorbol-13-acetate. Unlike 12-O-tetradecanoylphorbol-13-acetate, 1 alpha,25(OH)2D3 did not interfere with the binding of epidermal growth factor or phorbol dibutyrate. 1 alpha,25(OH)2D3 did not induce ornithine decarboxylase. Moreover, it did not activate protein kinase C in quiescent BALB 3T3 cells or this enzyme isolated from mouse brain. BALB 3T3 cells and their transformants contain a specific cytosol receptor for 1 alpha,25(OH)2D3, but the binding sites of the transformants were fewer and had lower affinity than those of untransformed BALB 3T3 cells. These effects of 1 alpha,25(OH)2D3 were specific, because other derivatives of vitamin D3 induced the same effects only at 200 times or more higher concentrations.

Topical application of 1 alpha,25-dihydroxyvitamin D3 [1 alpha,25(OH)2D3], an active form of vitamin D3, was previously shown to inhibit the induction of ornithine decarboxylase (ODC) and tumor promotion by tumor promoters in mouse skin. In the present study, this observation in skin was extended to other tissues, such as the stomach, colon, and liver, using 1 alpha-hydroxyvitamin D3 [1 alpha (OH)D3], which is converted to 1 alpha,25(OH)2D3 in the liver without hormonal control and thus evokes the systemic effects, if any, of 1 alpha,25(OH)2D3. When mice were given 1 alpha (OH)D3 at a dose of 5 micrograms by gastric tube, their plasma level of 1 alpha,25(OH)2D3 increased to a peak of about 18-fold the normal level after 12 h, followed by hypercalcemia (about 14 mg/dl), which reached a peak on Days 2 to 3. In 1 alpha (OH)D3-treated mice, induction of epidermal ODC by 12-O-tetradecanoylphorbol-13-acetate was markedly inhibited, the inhibition being maximal 2 to 4 days after 1 alpha (OH)D3 administration. ODC induction in the glandular stomach mucosa of rats by NaCl, a tumor promoter in stomach carcinogenesis, was also inhibited dose and time dependently by 1 alpha (OH)D3. Similarly, 1 alpha (OH)D3 treatment of rats markedly inhibited the induction of ODC in the colon mucosa by deoxycholate, a tumor promoter of colon carcinogenesis, and of ODC in the liver by phenobarbital, a promoter of liver carcinogenesis. These results suggest that an active form of vitamin D3 has a systemic inhibitory effect on induction of ODC activity by tumor promoters.