Specific inhibitory effects of guanosine on breast cancer cell proliferation.

Breast cancer is the most commonly diagnosed cancer and the leading cause of cancer-related death. Drug therapy for breast cancer is currently selected based on the subtype classification; however, many anticancer drugs are highly cytotoxic. Since intracellular levels of GTP are elevated in many cancer cells that undergo a specific cell proliferation cycle, GTP has potential as a target for cancer therapy. The present study focused on nucleosides and nucleotides and examined intracellular GTP-dependent changes in cell proliferation rates in normal (MCF-12A) and cancer (MCF-7) breast cell lines. Decreased cell proliferation due to a reduction in intracellular GTP levels by mycophenolic acid (MPA), an inosine monophosphate dehydrogenase inhibitor, was observed in both cell lines. The inhibitory effects of MPA on cell proliferation were suppressed when it was applied in combination with Guanosine (Guo), a substrate for GTP salvage synthesis, while the single exposure to Guo suppressed the proliferation of MCF-7 cells only. Although the underlying mechanisms remain unclear, since the inhibitory effects of Guo on cell proliferation did not correlate with GTP or ATP intracellular levels or the GTP/ATP ratio, there may be another cause besides GTP metabolism. Guo inhibited the proliferation of MCF-7, a human breast cancer cell line, but not MCF-12A, a human normal breast cell line. Further studies are needed to investigate the potential of applying Guo as a target for the development of a novel cancer treatment system.

Proposal of an in vitro thrombus-growth model for evaluating anticoagulants.

The general anticoagulant evaluation requires high expense equipment, reagents, and space. Therefore, not all laboratories can perform research related to anticoagulant. In this study, we propose a novel simple method "in vitro thrombus-growth model" that can evaluate anticoagulant ability by measuring weight. The in vitro thrombus-growth model is prepared by creating a "growth-clot" with citrate plasma, calcium chloride, and thrombin, and then pouring new citrate plasma onto it. The prepared growth-clots were increased in volume in citrated human plasma, including surpluses calcium chloride, which was released slowly, leading to clot coagulation around the plasma. As a result of evaluating the anticoagulant ability of direct thrombin inhibitor using this in vitro thrombus-growth model, it was confirmed that clot growth was suppressed in a concentration-dependent manner. Therefore, this thrombus-growth model is useful as a primary anticoagulant test that can to discover compounds with anticoagulant activity perform in any laboratory.

Lactose hydrate can increase the transcellular permeability of ß-naphthol in rat jejunum and ileum.

BACKGROUND: The unstirred water layer (UWL) is an integral part of the apical surface of mucosal epithelia and comprises mucins (MUC), for which there are many molecular species. Galectins, a family of ß-galactoside-binding lectins, form a lattice barrier on surface epithelial cells by interacting with MUC. Lactose inhibits the galectin-MUC interaction. Therefore, the present study investigated the galectin-MUC interaction in the mucosa of the gastrointestinal tract and its role in intestinal barrier functions. MATERIALS AND RESULTS: The effects of lactose hydrate (LH) on the membrane permeability of the rat small intestine and Caco-2 cells were examined. LH enhanced the membrane permeability of the rat small intestine, which contains the UWL, via a transcellular route, for which the UWL is the rate limiting factor. The membrane permeability of Caco-2 cells, in which the UWL is insufficient, was not affected by LH. The apparent permeability coefficient (Papp) of a paracellular marker was not significantly altered in the rat small intestine or Caco-2 cells treated with LH at any concentration. Furthermore, the Papp of ß-naphthol which is a transcellular marker was not significantly altered in Caco-2 cells treated with LH, but was significantly increased in the rat small intestine in a LH concentration-dependent manner. CONCLUSIONS: The present results demonstrate that the physical barrier has an important function in gastrointestinal membrane permeability, and LH-induced changes increase the transcellular permeability of ß-naphthol in rat small intestine.

[A University Approach to Promoting the Proper Formulation and Use of Hospital Preparations].

　Hospital preparations (HPs) prepared by hospital pharmacists have contributed to advanced medical care which is custom tailored to various and individual medical needs. Advanced pharmaceutical knowledge and skills are needed to properly prepare HPs. Hospital pharmacists have inherited formulations and the skills to prepare them from their predecessors. However, there has been an ongoing decrease in the number of HPs prepared in hospitals due to an increase in the availability of commercial formulations. Despite this trend, it is not acceptable for hospital pharmacists to lack experience when a doctor requests an original HP. We often refer to "The Hospital Preparation Casebook" when HPs are prepared. However, evidence for drug management and clinical evaluation of HPs in the book are frequently insufficient; it is difficult to keep the information up to date. Therefore, we consider that it is the role of universities to support the supply and usage of HPs in cooperation with hospital pharmacists and pharmacies. Here we report a trial that adopted a physicopharmaceutical approach to developing a HP of a mianserin hydrochloride suppository.

The pharmacokinetics of mianserin suppositories for rectal administration in dogs and healthy volunteers: a pilot study.

BACKGROUND: We formulated mianserin suppositories for the treatment of delirium and evaluated their pharmacokinetics by measuring plasma drug concentrations in dogs and healthy human volunteers. METHODS: Mianserin suppositories were prepared by a melting technique using Tetramide® tablets and Witepsol H-15 as the suppository base. Pharmacokinetics of this 30-mg mianserin preparation were evaluated in three beagle dogs and three healthy adult males, in line with ethics committee approval. Plasma mianserin levels were determined using gas chromatography-mass spectrometry. RESULTS: In dogs, the maximum plasma mianserin concentration (Cmax) was 1.3 ± 0.4 ng/mL, the time to Cmax (tmax) was 5.5 ± 4.3 h, and the area under the plasma concentration-time curve from 0 to 24 h (AUC0-24) was 18.9 ± 1.9 h・ng/mL. In humans, the Cmax was 14.6 ± 6.3 ng/mL, the tmax was 8 h, and the AUC0-24 was 266 ± 103 h・ng/mL. CONCLUSIONS: The current study characterized the pharmacokinetics of mianserin suppositories in dogs and humans. As compared to oral administration, the suppositories produced a lower Cmax and a delayed tmax, although AUC0-24 values were comparable. It will be necessary to identify an appropriate dose that produces an adequate plasma mianserin concentration for effective and safe clinical use. TRIAL REGISTRATION: UMIN000013853.

[Influence of temperature and humidity on physico-pharmaceutical characteristics of Rasilez(®) tablets].

Rasilez(®) tablets (RTs) contain the active ingredient aliskiren, which is a direct renin inhibitor of the renin-angiotensin system and used for the treatment of hypertension. We examined the influence of temperature and humidity on the physico-pharmaceutical characteristics (mass, volume, hardness, elution) of RTs. The RTs were preserved under conditions in which the temperature and humidity were altered using the second-order spherical composite experimental design for multi-objective problems. The characteristics of RTs were influenced more by the humidity than temperature, and differed markedly with over 55% relative humidity (RH). The mass and volume were increased with increasing humidity, and the tablets swelled. The hardness after vacuum-drying of the tablets, which preserved moisture conditions, was increased. Semitransparent particles were observed in the cross-section of the drying tablets in which aliskiren crystal forms were changed to amorphous forms. The mean dissolution time (MDT) of tablets was reduced with increasing humidity. The critical relative humidity (CRH) of the tablets was 36.1%RH at 30°C. These results suggest that RTs, on moisture absorption, showed changes in not their appearance and hardness, but also in crystal forms and the elution characteristics of aliskiren.

[Physicopharmaceutical characteristics of ulinastatin vaginal suppositories prepared in a hospital].

We studied a locally applied vaginal preparation (vaginal suppositories) of ulinastatin (urinary trypsin inhibitor, UTI), designed to threatened premature delivery and maintain pregnancy. Witepsol S55 was chosen as the basic component of the vaginal suppositories based on the physical pharmaceutical characteristics of three kinds of hard fats. The average particle size of the UTI aqueous injection was approximately 70% as compared with that of the UTI lyophilized product, used as the base material for the preparation of UTI vaginal suppositories. We compared the physical pharmaceutical properties of UTI vaginal suppositories with water contents of 2.5%, 5.0%, and 7.5%, respectively. Preparation strength negatively correlated with the water content. The coefficient of viscosity positively correlated with the water content of the preparation. UTI vaginal suppositories with a water content of 5.0% had the highest average drug release rate on moment analysis. A comprehensive evaluation of the properties of UTI vaginal suppositories, including high strength due to disintegration resistance, the coefficient of viscosity and its influence on local retention, and drug release and its influence on the duration of effect, indicated that a 5.0% UTI aqueous solution for injection combined with Witepsol S55 as the base was the optimal formulation for the hospital preparation of vaginal suppositories.

Identification, Cloning, and Characterization of l-Phenylserine Dehydrogenase from Pseudomonas syringae NK-15.

The gene encoding d-phenylserine dehydrogenase from Pseudomonas syringae NK-15 was identified, and a 9,246-bp nucleotide sequence containing the gene was sequenced. Six ORFs were confirmed in the sequenced region, four of which were predicted to form an operon. A homology search of each ORF predicted that orf3 encoded l-phenylserine dehydrogenase. Hence, orf3 was cloned and overexpressed in Escherichia coli cells and recombinant ORF3 was purified to homogeneity and characterized. The purified ORF3 enzyme showed l-phenylserine dehydrogenase activity. The enzymological properties and primary structure of l-phenylserine dehydrogenase (ORF3) were quite different from those of d-phenylserine dehydrogenase previously reported. l-Phenylserine dehydrogenase catalyzed the NAD(+)-dependent oxidation of the ß-hydroxyl group of l-ß-phenylserine. l-Phenylserine and l-threo-(2-thienyl)serine were good substrates for l-phenylserine dehydrogenase. The genes encoding l-phenylserine dehydrogenase and d-phenylserine dehydrogenase, which is induced by phenylserine, are located in a single operon. The reaction products of both enzymatic reactions were 2-aminoacetophenone and CO(2).

Characterization of the epitopes specific for the monoclonal antibody 9F5-3a and quantification of oxidized HDL in human plasma.

BACKGROUND: We previously isolated a monoclonal antibody, 9F5-3a, that is specific for HDL oxidized by CuSO(4). METHODS: We examined the characteristics of the 9F5-3a epitope by Western blot and measured the concentration of oxidized HDL in human plasma by enzyme-linked immunosorbent assay using this antibody. RESULTS: The monoclonal antibody specifically reacted with oxidized HDL in a mixture of HDL, LDL and modified lipoproteins. Oxidation of the HDL particles accelerated cross-linkage of apolipoproteins caused by lipid peroxidation, and the cross-linked apolipoprotein AI selectively reacted with the 9F5-3a antibody. Mean (standard deviation) plasma concentrations of oxidized HDL were 127 (50) microg/L in 23 healthy controls, 191 (65) microg/L in 30 patients with non-insulin-dependent diabetes mellitus (P < 0.01 versus healthy controls) and 200 (87) microg/L in 25 patients with coronary artery disease (P < 0.01 versus healthy controls). The concentrations of oxidized HDL did not correlate with the concentrations of thiobarbituric acid-reactive substances. CONCLUSIONS: The results indicate that determination of oxidized HDL concentration may be useful for identifying patients with atherosclerotic disease.

Elafin-overexpressing mice have improved cardiac function after myocardial infarction.

Elevated serine elastase activity after myocardial infarction can contribute to remodeling associated with left ventricular dilatation and dysfunction. We therefore assessed the effects of overexpressing the selective serine elastase inhibitor elafin in transgenic mice in which a myocardial infarction was caused by ligation of the left anterior descending coronary artery (LAD). Elevated serine elastase activity was observed in nontransgenic littermates as early as 6 h after LAD ligation and persisted at 4 and 7 days but not in sham-operated or elafin-overexpressing transgenic mice. Myeloperoxidase activity (index of inflammatory cells) and matrix metalloproteinase 2 were also increased but only at 4 and 7 days and only in nontransgenic mice (P < 0.05 for both comparisons), and this increase correlated with inflammatory cell infiltration. Echocardiographic study at 4 days revealed indexes of diastolic dysfunction in nontransgenic versus elafin-overexpressing mice (P < 0.05). Morphometric and biochemical analyses at 28 days indicated impairment in cardiac performance, with greater scar thinning and infarct expansion in nontransgenic versus elafin transgenic littermates (P < 0.05 for all comparisons). Thus serine elastase inhibition appears to suppress inflammation, cardiac dilatation, and dysfunction after myocardial infarct.

A patient with severe hypertriglyceridemia associated with anemia and hypoalbuminemia.

We report a patient with severe hypertriglyceridemia associated with anemia and hypoalbuminemia, in which the former may have caused the latter two conditions. This is the first reported case of abrupt onset of severe hypertriglyceridemia resulting in suppression of bone marrow and liver function.

Glycated high-density lipoprotein regulates reactive oxygen species and reactive nitrogen species in endothelial cells.

Nonenzymatic glycosylation of plasma proteins may contribute to the excess risk of developing atherosclerosis in patients with diabetes mellitus. Although it is believed that high-density lipoprotein (HDL) is glycosylated at an increased level in diabetic individuals, little is known about a possible linkage between glycated HDL and endothelial dysfunction in diabetes. To clarify whether glucose-modified HDL affects the function of endothelial cells, we first examined herein the level of H(2)O(2) generation from cultured human aortic endothelial cells (HAECs) exposed to a glycated oxidized HDL (gly-ox-HDL) prepared in vitro. Incubation for 48 hours with 100 microg/mL of gly-ox-HDL induced significant release of H(2)O(2) from cells and gly-ox-HDL-induced H(2)O(2) formation was inhibited in the presence of diphenyleneiodonium, an inhibitor of NADPH oxidase. In addition, stimulation of HAECs with gly-ox-HDL for 48 hours elicited a marked downregulation of catalase and Cu(2+), Zn(2+)-superoxide dismutase (CuZn-SOD), suggesting H(2)O(2) formation by gly-ox-HDL to be due to a disturbance involving oxidant and antioxidant enzymes in the cells. Treatment of HAECs with gly-ox-HDL attenuated the expression of endothelial nitric oxide synthase (eNOS), but not inducible nitric oxide synthase (iNOS), and this was followed by decreased production of nitric oxide (NO) by the cells. Furthermore, in vitro experiments with glycated HDL (gly-HDL) in the presence of 2 mmol/L EDTA and Cu(2+)-oxidized HDL suggested the effect of gly-HDL on endothelial function to be possibly potentiated by additional oxidative modification. Taking all of the above findings together, gly-ox-HDL may lead to the deterioration of vascular function through altered production of reactive oxygen species and reactive nitrogen species in endothelial cells.