Apoptosis induced by inhibition of contact with extracellular matrix in mouse collecting duct cells

Cell-matrix interactions have major effects upon phenotypic features such as gene regulation, cytoskeletal structure, differentiation and aspects of cell growth control. Detachment from the matrix epithelial cells induces programmed cell death, and this cell detachment induced apoptosis has been referred to as 'anoikis'. This study was undertaken to determine whether apoptosis is induced by inhibition of contact with extracellular matrix (ECM) in collecting duct cells and to investigate the signaling mechanisms of the process. Upon detachment from ECM, mouse inner medullary collecting duct cells (mIMCD-3) and mouse outer cortical collecting duct cells (M-1), which were derived from an SV40 transgenic mouse, entered into programmed cell death. Forced suspension of mIMCD-3 or M-1 cells did not affect the expression of Bcl-2-related proteins and did not activate c-Jun NH(2)-terminal kinase. Detachment of cells from ECM activated p38 mitogen-activated protein kinase (p38), but its inhibition with SB203580 did not protect cells from anoikis. Detachment of cells from matrix inhibited NF-kappaB activity, and the inhibition of NF-kappaB activity by overexpression of nonphosphorylatable I-kappaB increased detachment-induced apoptotic cell death in M-1 cells. Forced suspension of M-1 cells still activated p53 activity. Caspase-8 was activated during anoikis, but the time course of its activation was in accordance with DNA fragmentation. These results indicate that detachment from ECM induces apoptosis in the kidney collecting duct cells. Changes in expression levels of Bcl-2-related proteins or activation of JNK/p38 kinase are not critical for anoikis. Decrease in NF-kappaB activity and activation of p53 induced by inhibition of interaction with ECM play roles in anoikis in SV-40-transformed collecting duct cells. Caspase-8 is activated during detachment-induced apoptosis, the mechanisms of which are independent of activation of cell death receptors. Copyright Copyright 1999 S. Karger AG, Basel     

Transfer of extensor carpi radialis longus or brevis for opponensplasty

For the restoration of thumb opposition many types of tendon transfer techniques have been described. The flexor digitorum superficialis (FDS) of the ring finger is commonly selected as a motor. On occasion, however, the quality of the flexor muscles of the fingers or wrist is not good enough for tendon transfer and another available muscle must be selected. In this situation, we have preferred to use an extensor carpi radialis longus (ECRL) or brevis (ECRB) transfer to restore opposition of the thumb. Follow-up examination, at an average 5 years and 10 months after operation, showed that the results of ten of 11 transfers were excellent and the other was good.     

A novel series of non-nucleoside inhibitors of inosine 5'-monophosphate dehydrogenase with immunosuppressive activity.

Inhibitors of inosine 5'-monophosphate dehydrogenase (IMPDH, EC 1.1.1.205) are effective immunosuppressive drugs that may also have additional potential applications as antitumour and antimicrobial agents. The clinical value of the most potent and specific inhibitor of IMPDH, mycophenolic acid, is limited by its rapid metabolism in vivo to an inactive glucuronide derivative. There is, therefore, a considerable incentive to develop structurally novel, preferably non-nucleoside, inhibitors with greater metabolic stability than mycophenolic acid. Here, we describe a high throughput screen for inhibitors of IMPDH, which facilitated the discovery of a single novel non-nucleoside inhibitor from a collection of approximately 80,000 compounds. The inhibitor is a pyridazine, which, like mycophenolic acid, exerts uncompetitive inhibition of IMPDH. Analysis of the enzyme kinetics suggests that the inhibitory action of the pyridazine is similar to that of mycophenolic acid, which involves trapping of a covalent intermediate formed during the conversion of IMP to xanthosine monophosphate. Chemical modification of the lead compound resulted in pyridazine derivatives with enhanced potency against IMPDH and guanine nucleotide synthesis in cultured cells in vitro and also against guanine nucleotide synthesis in the mouse spleen in vivo. One of the compounds was available in sufficient quantity to demonstrate highly effective immunosuppressive activity in a model of delayed type hypersensitivity in mice. To our knowledge, the novel pyridazines described in this report represent the first non-nucleoside uncompetitive inhibitors of IMPDH with immunosuppressive activity since the discovery of the inhibitory activity of mycophenolic acid and its derivatives thirty years ago.     

Identification of urinary metabolites of clemastine after oral administration to man

The metabolism of clemastine, 2-[2-[1-(4-chlorophenyl)-1-phenylethoxylethyl])-1-methylpyrrolidin e, has been studied in three adult male volunteers after a single oral dose of 20 mg as the fumarate. After enzymatic hydrolysis solvent extracts of urine were derivatized with N-methyl-N-trimethylsilyltrifluoroacetamide-ammonium iodide and analysed by gas chromatography-mass spectrometry. The structures of metabolites were determined on the basis of electron impact and chemical ionization mass spectra and the identities of some (e.g. carbinol, 4-chlorobenzophenone and 4-chlorophenylstyrene) were confirmed by use of authentic standards. The principal route of metabolism of clemastine in man involves direct oxidation, O-dealkylation (fission of the ether bond), aromatic hydroxylation, aliphatic oxidation, alcoholic dehydration, and then enzymatic hydrolysis. Of the total amount of metabolites excreted in the urine 35% was carbinol (metabolite M3, major metabolite), 15% was M1, 17% was M2, 11% was M4, 9% was M5, 8% was M6 and 5% was M7.     

Inhibitory effect of triterpenes from Crataegus pinatifida on HIV-I protease.

The methanol extracts of the leaves of Crataegus pinnatifida showed potent inhibitory activities against HIV-1 protease at a concentration of 100 micrograms/ml. The subsequent fractionation and isolation of the extract gave two active compounds. Their structures were identified as uvaol (1) and ursolic acid (2) by spectral data. These active compounds inhibit HIV-1 protease with IC50 values of 5.5 and 8.0 microM, respectively.     

Acyl-CoA:Cholesterol Acyltransferase Inhibitory Activity of Lignans Isolated from Schizandra, Machilus and Magnolia Species

Fifteen lignans were isolated from the fruits of SCHIZANDRA CHINENSIS, the leaves of MACHILUS THUNBERGII, and the flower buds of MAGNOLIA DENUDATA. They were identified as gomisins, schizandrin, wuweizisu, schizantherin, licarins, and machilin, which inhibited rat liver ACAT with IC (50) values of 25-200 microM. Comisin N is the most potent inhibitor with IC (50) value of 25 microM in these lignans.     

Bioisosterism: Interchange of 4-OH to 4-NH2 in vanillin or homovanillin ring of capsaicinoids

A series of 4-amino Capsaicin analogs 15, 17 and 19 were prepared to investigate the bioisosteric effect of 4-amino group, and all these compounds exhibited moderate or weak potency from their analgesic test. From our previous results and others, 4-hydroxyl group as well as 3-methoxy substituent could be crucial for high analgesic activity. This biological result also shows that the activity is sensitive to alkyl chain length in hydrophobic region and the phenylacetic amides 19 are more active than the corresponding urea derivatives 17.     

Psammaplin A, a natural bromotyrosine derivative from a sponge, possesses the antibacterial activity against methicillin-resistantStaphylococcus aureus and the DNA gyrase-inhibitory activity

Psammaplin A, a natural bromotyrosine derivative from an associated form of two sponges (Poecillastra sp. and Jaspis sp.) was found to possess the antimicrobial effect on the Gram-positive bacteria, especially on methicillin-resistant Staphylococcus aureus (MRSA). The minimal inhibitory concentration of psammaplin A against twenty one MRSAs ranged from 0.781 to 6.25 microg/ml, while that of ciprofloxacin was 0.391-3.125 microg/ml. Psammaplin A could not bind to penicillin binding protein, but inhibited the DNA synthesis and the DNA gyrase activity with the respective 50% (DNA synthesis) and 100% (DNA gyrase) inhibitory concentration 2.83 and 100 microg/ml. These results indicate that psammaplin A has a considerable antibacterial activity, although restricted to a somewhat narrow range of bacteria, probably by inhibiting DNA gyrase.     

Synthesis of 4-hydroxy-1-thiocoumarin derivatives-1: An efficient synthesis of thioflocoumafen

An efficient procedure for the preparation of 4-hydroxy-3-{1,2,3,4-tetra-hydro-3-[4-(4-triflu-oromethylbenzyl oxy)phenyl]-1-naphthyl}thiocoumarin (thioflocoumafen, 1a and 1b) is described. The key step in the synthesis involves the condensation reaction of 3-(4-methoxyphenyl)-1-tetralol (2) with 4-hydroxy-1-thiocoumarin (3).     

Inducible nitric oxide synthase inhibitors fromMelia azedarach var.Japonica

In bioassay-guided search for inducible nitric oxide synthase (iNOS) inhibitory compounds from higher plants of South Korea, two beta-carboline alkaloids, 4-methoxy-1-vinyl-beta-carboline (1) and 4,8-dimethoxy-l-vinyl-beta-carboline (2) have been isolated from the cortex of Melia azedarach var. japonica. The structures of these compounds were elucidated on the basis of spectroscopic data. Compounds 1 and 2 showed marked inhibitory activity of iNOS on LPS- and interferon-gamma-stimulated RAW 264.7 cells.