Influence of losartan intake on the circadian rhythm of melatonin secretion in humans.

It has been reported that losartan, an angiotensin II receptor blocker, alters the circadian rhythm of melatonin secretion and significantly reduces melatonin production. However, this finding has been confirmed at the animal experiment level only, and there are no reports of studies in humans. Therefore, we performed this study to confirm the reproducibility of the aforementioned findings of animal experiments in humans. Ten male subjects who were in good general health and free from any medical condition were recruited for this study. After a preliminary observation period of 7 days, the subjects received oral losartan treatment, 50 mg daily for 7 days. Blood samplings for measurement of the plasma melatonin concentrations were performed on day 7 of the preliminary observation period and day 7 of the losartan treatment period. The circadian rhythm of melatonin secretion after the 7-day treatment with losartan showed no significant difference from that recorded before the losartan administration. The significant decrease of the home blood pressure was observed on the afternoons. The blood samples showed significant decrease of the serum sodium and uric acid levels, along with a significant increase of the serum potassium level. The pharmacological actions of losartan at the ordinarily used clinical dose level were confirmed in humans, however, no significant inhibitory effect of the drug on melatonin secretion could be confirmed. These results are expected to be useful for guiding the proper use of angiotensin II receptor blockers.

Predominant prevalence of arterial thrombosis in Japanese patients with antiphospholipid syndrome.

OBJECTIVE: To study the clinical and immunological manifestations of antiphospholipid syndrome (APS) in the Japanese population by a single-centre registration. METHODS: In this retrospective cohort study, 141 consecutive patients with APS, fulfilling the Sydney revised Sapporo criteria for definite APS, who visited our autoimmune clinic from 1988 to 2010, were recruited and followed up. All the patients were interviewed and underwent a general physical examination by qualified rheumatologists on the day of blood sampling. RESULTS: The population comprised 119 woman and 22 men with a mean age at diagnosis of 44 years (range 9-79 years). Seventy patients (49.6%) had primary APS, and 71 (50.4%) had systemic lupus erythematosus. The prevalence of thrombosis was 85.8 per cent, arterial thrombosis was found in 93 patients (66.0%) and venous thrombosis was found in 46 patients (32.6%). The most common thrombosis was cerebral infarction [86/141 (61.0%)] followed by deep vein thrombosis [33/141 (23.4%)]. Among 70 pregnant women, 45 (64.3%) had obstetric complications. Lupus anticoagulant was detected in 116 patients (82.3%), anticardiolipin antibodies in 83 (58.9%), anti-ß2 glycoprotein I antibodies in 73 (51.8%) and phosphatidylserine-dependent antiprothrombin antibodies in 98 (69.5%). CONCLUSION: High prevalence of arterial thrombosis was noted in Japanese patients with APS. The profile of heterogeneous and complex clinical manifestations was substantiated in Japanese patients with APS.

The short-term role of corticosteroid therapy for pulmonary arterial hypertension associated with connective tissue diseases: report of five cases and a literature review.

Pulmonary arterial hypertension (PAH) is a life-threatening complication in connective tissue diseases (CTD). It remains controversial whether immunosuppressive therapy is useful for PAH associated with CTD (PAH-CTD). The Dana Point algorithm does not refer such treatments in patients with PAH-CTD due to the lack of evidence. However, some case reports have shown the potential efficacy of immunosuppression for PAH-CTD. Here we report five cases of PAH-CTD treated with corticosteroids and discuss the current management of PAH-CTD with immunosuppressive agents. Our cases consisted of three active systemic lupus erythematosus (SLE), a quiescent SLE and an active polymyositis. WHO functional classes at baseline were class III in three cases and class II in two. Median follow-up period was 44 (28-92) weeks. PAH was diagnosed by right heart catheterization in all cases (median pulmonary arterial pressure was 45 (29-49) mmHg). All patients received 1 mg/kg of prednisolone (PSL) for 2-4 weeks, followed by appropriate dose reduction. Methylprednisolone pulse therapy was performed in patients resistant to the high dosage of PSL. Four patients received vasodilators in combination. The therapy as above improved WHO functional class 4 weeks after the initiation of PSL in all the patients. Two patients required dose increase or additional administration of vasodilators due to the dose reduction of PSL. Corticosteroid therapy may be effective for PAH-CTD at least in the short term, even in low general activity of CTD or moderate PAH. Our experience suggests that corticosteroid therapy, by itself or in conjunction with standard vasodilators, is effective for PAH-CTD patients.

One-way EZ-isomerization of bis(n-butylammonium) (Z,Z)-muconate under photoirradiation in the crystalline state.

One-way EZ-isomerization of bis(n-butylammonium) (Z,Z)-muconate [(Z,Z)-hexa-2,4-diene-1,6-dioate] to the corresponding (E,E)-isomer quantitatively proceeded in the crystalline state under photoirradiation with a high-pressure mercury lamp, being a new type of crystal-to-crystal reaction.

Intercalation of alkylamines into an organic polymer crystal

Organic solid-state synthesis allows formation of products that are difficult or impossible to produce by conventional methods. This feature, and the high degree of reaction selectivity that can be achieved, is a direct result of the control over the relative orientation of the reactants afforded by the solid state. But as the successful development of 'topochemical reactions' requires the careful design of suitable reactant crystals, the range of both reactions and products amenable to this approach has been limited. However, recent advances in organic crystal engineering, particularly the rational design of complex solid architectures through supramolecular preorganization, have renewed interest in topochemical reactions. Previously, we have orientated muconate monomers--diene moieties with a carboxylate group on each end--using long-chain n-alkylammonium ions, such that the topochemical photopolymerization of the solid-state reactants produces layered crystals of stereoregular and high-molecular-mass polymers. Here we show that these polymer crystals are capable of repeated, reversible intercalation by conversion to the analogous poly(carboxylic acid), followed by transformation into a number of poly(alkylammonium muconate)s upon addition of the appropriate amine. Introduction of functional groups into these crystals may allow the design of organic solids for applications such as molecular recognition, separation and catalysis, thereby extending the range and practical utility of current intercalation compounds.

Enhancement by dimethyl sulfoxide of 1,25-dihydroxyvitamin D3-induced differentiation in human promyelocytic HL-60 leukemia cells requires dimethyl sulfoxide-induced G0/G1 arrest.

We investigated the induction of differentiation in human promyelocytic HL-60 leukemia cells by a relatively low concentration of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). The cells were markedly induced to differentiate by combined treatment with reduced concentrations of dimethyl sulfoxide (DMSO) and 1,25(OH)2D3, neither of which alone had much of an effect on differentiation. At 48 hr post-treatment, a greater proportion of DMSO- and DMSO/1,25(OH)2D3-treated, but not 1,25(OH)2D3-treated, cells were in G0/G1 than untreated cells. Our study indicates that the synergistic effect of DMSO and 1,25(OH)2D3 on the induction of differentiation in HL-60 cells requires DMSO-induced G0/G1 arrest.

Induction of apoptosis by hinokitiol, a potent iron chelator, in teratocarcinoma F9 cells is mediated through the activation of caspase-3.

Hinokitiol, a potent iron chelator, has been reported to induce differentiation in teratocarcinoma F9 cells with a reduction of viable cells. In this study, we examined the steps leading to eventual cell death by hinokitiol during differentiation. Hinokitiol induced DNA fragmentation of F9 cells in a concentration- and time-dependent manner. This effect was also observed in a cell-free system using the nuclei from intact cells and the cytosols from hinokitiol-treated cells. In contrast, hinokitiol methyl ether and hinokitiol-Fe (III) complex, which are deficient in iron-chelating activity, showed no DNA fragmentation activity in both cell culture and cell-free systems. These results suggest that iron deprivation by hinokitiol may be involved in the induction of apoptosis of F9 cells. Caspase-3, one of the key enzymes in the apoptotic cascade, was specifically activated by hinokitiol treatment, but not by the other two derivatives. In addition, its specific inhibitor, benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone, strongly blocked hinokitiol-induced DNA fragmentation. These results indicate that iron deprivation by hinokitiol can induce apoptosis of F9 cells through the activation of caspase-3.

Mannosylphosphate transfer to yeast mannan.

Mannoproteins located in the outermost layer of yeast cell wall determine the wall's porosity and thereby regulate leakage of proteins from the periplasmic space and entrance of macromolecules from the environment. In several yeasts, including Saccharomyces cerevisiae, the glycan portion of mannoproteins is composed not only of neutral oligosaccharides containing mannose and N-acetylglucosamine, but also of acidic oligosaccharides containing mannosylphosphate. The mannosylphosphate residues confer a net negative charge on the cell wall, and so change the properties and environment of the cell surface. Progress on mannosylphosphorylation and its regulation in S. cerevisiae is summarized. Two genes required for mannosylphosphate transfer, MNN4 and MNN6, have been cloned, and a functional analysis of these genes suggests a mechanism for mannosylphosphate transfer. Possible functions for mannosylphosphate transfer in yeast are also discussed. These include supply of GMP for sugar nucleotide transport in the Golgi, cross-linking of mannoproteins to beta-glucan, and a cellular stress response to environmental changes. Glycans in pathogenic yeast and protozoa are also modified with mannosylphosphate, and the potential contribution of this modification to the pathogenicity of these organisms is evaluated.

Mannosylphosphate transfer to cell wall mannan is regulated by the transcriptional level of the MNN4 gene in Saccharomyces cerevisiae.

Mannosylphosphorylation is a major oligosaccharide modification that provides negative charge in the Saccharomyces cerevisiae cell wall. Although two genes, MNN6 and MNN4, which encode a mannosylphosphate transferase and its putative positive regulator, respectively, are involved in this modification, the amount of Mnn4p has been found to be a limiting factor for mannosylphosphorylation. The level of mannosylphosphorylation increased at late-logarithmic and stationary phases of cell growth, and this was correlated to the transcriptional enhancement of MNN4. We also find that mannosylphosphate transfer to mannan is negatively regulated by the protein kinase A pathway, while the presence of 0.5 M potassium chloride enhanced MNN4 transcription. This type of transcriptional regulation is observed in many stress response genes, implying that mannosylphosphate transfer is involved in the cellular response to a variety of stresses.

Cloning and analysis of the MNN4 gene required for phosphorylation of N-linked oligosaccharides in Saccharomyces cerevisiae.

The Saccharomyces cerevisiae MNN4 gene, which is involved in mannosylphosphate transfer from GDP-mannose to N-linked oligosaccharide, has been cloned from a lambda phage containing a yeast chromosome XI DNA fragment. The MNN4 ORF encodes a protein of 1178 amino acids. The deduced amino acid sequence shows a topology of type II membrane proteins and has a unique repeated sequence of lysine and glutamic acid at the C-terminus. Disruption and overexpression of MNN4 led to a decrease and increase, respectively, of the mannosylphosphate content in cell wall mannans prepared from both mnn4 and wild type strains. A dramatic decrease of mannosylphosphate occurs in delta mnn4 mutans. The results from genetic and biochemical experiments combine to suggest that Mnn4p is required to mediate mannosylphosphate transfer in both the core and outer chain portions of N-linked oligosaccharides.

[Pharmacological study on kefir--a fermented milk product in Caucasus. I. On antitumor activity (1)].

The antitumor activity of kefir (YK-1), a fermented milk product in Caucasus, was investigated. YK-1 at oral doses of 100 or 500 mg/kg inhibited the proliferation of solid tumor of Ehrlich ascites carcinoma transplanted subcutaneously in mice. YK-1 did not show an inhibitory effect on the ear swelling induced contact dermatitis caused by picryl chloride (PC-CD). However, YK-1 inhibited the immunosuppression in Ehrlich carcinoma-bearing mice and with the frozen and dried ascites of the tumor-bearing mice containing immunosuppressive substances (EC-sup) in PC-CD-induced mice. And also, YK-1 activated the immunosuppressive activity of spleen cells of mouse treated with EC-sup. These results suggest that YK-1 may have antitumor activity against Ehrlich carcinoma and activate the immunosuppression with it.

[Cytotoxicity of Corylifoliae fructus. I. Isolation of the effective compound and the cytotoxicity].

The ethanol extract of Psoraleae Fructus (Psoralea corylifolia L.) was found to have cytotoxic activity against L929-cells in cell culture. The active compound was isolated by column chromatography on silica gel and identified as bakuchiol by means of spectral evidence. The cytotoxic activity of bakuchiol in cell culture was observed in short time and found to be unreversible. The mechanism of the cytotoxic activity was considered to be due to an injury of cell membrane from electron microscopic observation and hemolytic activity.

[Cytotoxicity of corylifoliae fructus. II. Cytotoxicity of bakuchiol and the analogues].

Bakuchiol is a major component of Corylifoliae Fructus (Psoralea corylifolia L.) and has been clarified to have cytotoxic activity. The chemical structure-cytotoxic activity relationship of bakuchiol was investigated by means of cytotoxic activity of synthesized analogues of bakuchiol and phenol. It was proved that an alkyl group was necessary for cytotoxic activity. But the double bonds in the unsaturated hydro-carbon group exerted but little influence on the cytotoxic activity. The cytotoxic activity of bakuchiol was the strongest as compared with that of the analogues examined.