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Warm ischemia and reperfusion injury (IRI) is a prognostic factor in donation after cardiac death donor transplantation. However, a reliable method to predict IRI before transplantation has not been established. The aim of this study was to identify predictive markers of hepatic IRI by simultaneous measurement of endogenous molecules using matrix-assisted laser desorption/ionization-imaging mass spectrometry (MALDI-IMS). Rats were subjected to hepatic warm ischemia (70%) for 30 or 90 minutes and subsequent reperfusion. The livers were collected at the end of ischemia and 1 hour, 6 hours, and 24 hours after reperfusion. The liver tissue sections were applied to IMS (m/z 200-2000). Candidate molecules were identified by tandem mass spectrometry. Imaging mass spectrometry (IMS) revealed a significant increase in the taurine conjugates of dihydroxycholanoic acid (TDHCA) during ischemia and a tendency to return to the basal level after reperfusion. Notably, high-resolution measurements revealed focal accumulation of TDHCA in the intrahepatic bile duct with ischemic time. In conclusion, IMS is a useful method to detect minute changes provoked by ischemia, which are barely detectable in assays involving homogenization. Accordingly, focal accumulation of TDHCA during ischemia may be a candidate marker for predicting later IRI.

Background: Heavy water (D2O) has many biological effects due to the isotope effect of deuterium. We previously reported the efficacy of D2O containing solution (Dsol) in the cold preservation of rat hearts. Here, we evaluated whether Dsol reduced hepatic cold preservation and reperfusion injury. Methods: Rat livers were subjected to 48-hour cold storage in University of Wisconsin (UW) solution or Dsol, and subsequently reperfused on an isolated perfused rat liver. Graft function, injury, perfusion kinetics, oxidative stress, and cytoskeletal integrity were assessed. Results: In the UW group, severe ischemia and reperfusion injury (IRI) was shown by histopathology, higher liver enzymes leakage, portal resistance, and apoptotic index, oxygen consumption, less bile production, energy charge, and reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio (versus control). The Dsol group showed that these injuries were significantly ameliorated (versus the UW group). Furthermore, cytoskeletal derangement was progressed in the UW group, as shown by less degradation of α-Fodrin and by the inactivation of the actin depolymerization pathway, whereas these changes were significantly suppressed in the Dsol group. Conclusion: Dsol reduced hepatic IRI after extended cold preservation and subsequent reperfusion. The protection was primarily due to the maintenance of mitochondrial function, cytoskeletal integrity, leading to limiting oxidative stress, apoptosis, and necrosis pathways.

O-Alkylhydroxylamines, particularly O-methylhydroxylamine, aminate nitroarenes in the presence of a strong base and a copper catalyst to give aminonitroarenes in good yields. ortho- or para-Amination with respect to the nitro group takes place, and in some cases the ortho-aminated product is preferentially obtained. With 3-substituted nitrobenzenes where the substituent has a lone pair of electrons, preferential amination occurs at the 2-position to give the sterically most congested 3c–f, 14 and 22g.

Tocoretinate (TR) is a hybrid compound composed of alpha-tocopherol esterified with retinoic acid. The present study was conducted to clarify whether or not TR affects DNA synthesis in a human intestinal cell line, FHs 74 Int. In these cells, addition of 10% serum resulted in an approximately 10-fold increase in DNA synthesis as assessed by [3H]thymidine incorporation. Epidermal growth factor (EGF) augmented DNA synthesis three- to fourfold. When EGF was added together with insulin-like growth factor-I (IGF-I), which had only a small effect by itself, a combination of these growth factors reproduced the effect of serum. In quiescent FHs 74 Int cells, TR had no effect on DNA synthesis by itself. However, when quiescent cells were pretreated with TR for 24 hr, DNA synthesis induced by EGF was markedly enhanced. Thus, in TR-pretreated cells, EGF stimulated DNA synthesis to the same extent as 10% serum. The effect of TR was dose-dependent and the maximal effect was obtained by 10(-7) M TR. Pretreatment with TR enhanced the effect of EGF on DNA synthesis but did not change the dose-response relationship for EGF-mediated DNA synthesis. All-trans-retinoic acid had similar stimulatory effect on EGF-induced DNA synthesis. When the medium was changed during the treatment with TR, the effect of TR on DNA synthesis was reduced. In addition, pretreatment with TR resulted in release of immunoreactive IGF-I into medium. Finally, the effect of TR was attenuated by an addition of antibody against IGF-I.(ABSTRACT TRUNCATED AT 250 WORDS)

The present study was conducted to monitor precisely the activity of protein kinase C (PKC) in adrenal glomerulosa cells stimulated by angiotensin II (ANG II). PKC activity in cells was monitored by measuring phosphorylation of a synthetic KRTLRR peptide, a specific substrate for PKC, immediately after the permeabilization of the cells with digitonin [Heasley and Johnson J. Biol. Chem. (1989) 264, 8646-8652]. Addition of 1 nM ANG II induced a gradual increase in KRTLRR peptide phosphorylation, which reached a peak at 30 min, and phosphorylation was sustained thereafter. When the action of ANG II was terminated by adding [Sar1,Ala8]ANG II, a competitive antagonist, both Ca2+ entry and KRTLRR phosphorylation ceased rapidly, whereas diacylglyercol (DAG) content was not changed significantly within 10 min. Similarly, when blockade of Ca2+ entry was achieved by decreasing extracellular Ca2+ to 1 microM or by adding 1 microM nitrendipine, KRTLRR peptide phosphorylation was decreased within 5 min. In addition, restoration of Ca2+ entry was accompanied by an immediate increase in KRTLRR peptide phosphorylation. Under the same condition, DAG content did not change significantly. We then examined the role of the PKC pathway in ANG II-induced aldosterone production. Ro 31-8220 inhibited ANG II-induced KRTLRR phosphorylation without affecting the activity of calmodulin-dependent protein kinase II. In the presence of Ro 31-8220, ANG II-mediated aldosterone production was decreased to approx. 50%. Likewise, intracellular administration of PKC19-36, a sequence corresponding to residues 19-36 of the regulatory domain of PKC known to inhibit PKC activity, attenuated ANG II-mediated activation of PKC and aldosterone output. These results indicate a critical role of Ca2+ entry in the regulation of PKC activity by ANG II.

O-Alkylhydroxylamines, particularly O-methylhydroxylamine, aminate nitroarenes in the presence of a strong base and a copper catalyst to give aminonitroarenes in good yields. ortho- or para-Amination with respect to the nitro group takes place, and in some cases the ortho-aminated product is preferentially obtained. With 3-substituted nitrobenzenes where the substituent has a lone pair of electrons, preferential amination occurs at the 2-position to give the sterically most congested 3c–f, 14 and 22g.

Homogeneous hydrogenation of 2-phenyl-3-methyl-2-butenoic acid derivatives in the presence of a catalytic amount of such chiral phosphine-rhodium complexes as Rh/(R)-BINAP, Rh/(R)-, or (S)-Cy-BINAP, Rh/(R)-p-tolyl-BINAP, and Rh/(R)-p-methoxy-phenyl-BINAP afforded the corresponding phenylacetic acid derivatives in high enantiomeric excesses and in quantitative chemical yields. The optically active phenylacetic acid derivatives are useful intermediates of agrochemicals and pharmaceuticals.

By treating of the oligoethylene glycol monocarboxymethyl ethers with p-toluenesulfonyl chloride in the presence of alkali metal carbonates, novel macrocyclic polyether-monoester compounds were obtained in moderate yield.

A new facile method of synthesizing crown ethers from oligoethylene glycols by treating them with arenesulfonyl or alkanesulfonyl chlorides in the presence of alkali metal hydroxide or alkoxide was described. 15-Crown-5 and 21-crown-7 were synthesized from pentaethylene glycol and heptaethylene glycol respectively in good yields, while 18-crown-6 was obtained from both hexaethylene glycol and triethylene glycol. Although the main product was 24-crown-8 in the reaction of tetraethylene glycol/TsCl/Na(K)OH in dioxane, 12-crown-4 was obtained in a moderate yield from the reaction of tetraethylene glycol/benzenesulfonyl chloride/t-BuOLi in t-BuOH. Furthermore, the analogous treatment of PEG 200 afforded a mixture of 15-, 18-, 21-, and 24-crown ethers. The reaction conditions were investigated, and the scope of the reaction was discussed.

3-Substituted 2-oxo crown ethers and a novel dioxo crown ether with a point symmetry were synthesized by the cyclization of the corresponding substituted oligoethylene glycol monocarboxymethyl ethers using benzenesulfonyl chloride in the presence of alkali metal carbonates. The reaction mechanism was discussed. Their stability constants toward sodium and potassium cations were determined and the relation between their structures and complexing properties was discussed.

ABS>The incidence of leukemia in RF mice exposed to a single whole-body irradiation of 350 r x-rays was 77.4%, in 41 out of 53 animals. In all, 20 developed the thymic and 20 the non-thymic lymphocytic leukemia, while only one developed myelogenous leukemia. The incidence of leukemia by 20- methylcholanthrene painting was 88% in 22 out of 25 animals. Of them, 12 developed lymphocytic leukemia and 10 myelogenous leukemia. Cell-free filtrates from the leukemic mice, which were induced by a single whole-body x irradiation, were inoculated to the newborn mice of the same strain less than 16 hours old. Two (18.7%) of the twelve inoculated animals developed leukemia on the 357th and 374th days, respectively, after the inoculation. Attempts to inoculate cell-free filtrate from 20-methylcholanthrene-induced leukemic RF mice to newborn mice of the same strain were successful. Cell-free filtrate from the myelogenous leukemic mouse caused lymphocytic leukemia in one of three inoculated mice. This is suggestive of the possibility of transformation of the type of leukemia during cell-free transmission. Virus-like particles were demonstrated by electron microscope in the lymph nodes of 20-methylcholanthrene-induced leukemic mice. The results suggest that x-ray and chemical carcinogens may act to induce leukemia or mammary carcinomamore » by the activation of a latent virus naturally resident in the RF mouse. (P.C.H.)« less

A new facile method of synthesizing crown ethers from oligoethylene glycols by treating them with arenesulfonyl or alkanesulfonyl chlorides in the presence of alkali metal hydroxide or alkoxide was described. 15-Crown-5 and 21-crown-7 were synthesized from pentaethylene glycol and heptaethylene glycol respectively in good yields, while 18-crown-6 was obtained from both hexaethylene glycol and triethylene glycol. Although the main product was 24-crown-8 in the reaction of tetraethylene glycol/TsCl/Na(K)OH in dioxane, 12-crown-4 was obtained in a moderate yield from the reaction of tetraethylene glycol/benzenesulfonyl chloride/t-BuOLi in t-BuOH. Furthermore, the analogous treatment of PEG 200 afforded a mixture of 15-, 18-, 21-, and 24-crown ethers. The reaction conditions were investigated, and the scope of the reaction was discussed.

3-Substituted 2-oxo crown ethers and a novel dioxo crown ether with a point symmetry were synthesized by the cyclization of the corresponding substituted oligoethylene glycol monocarboxymethyl ethers using benzenesulfonyl chloride in the presence of alkali metal carbonates. The reaction mechanism was discussed. Their stability constants toward sodium and potassium cations were determined and the relation between their structures and complexing properties was discussed.

Sulfur or nitrogen analogues of monooxo crown ethers were prepared via intramolecular cyclization of the corresponding thia or aza oligoethylene glycol carboxylmethyl ethers by using benzenesulfonyl chloride in the presence of alkali metal carbonates.