OBJECTIVE To examine the effect of iron on the prostaglandin (PG) E2 production by human synovial fibroblasts in vitro. METHODS Human synovial fibroblasts were isolated from synovial tissue of rheumatoid arthritis (RA) and osteoarthritis (OA) patients and cultured in medium. Synovial fibroblasts were stimulated by human recombinant interleukin (IL) 1 beta (0.1-10 ng/ml) with or without ferric...

The interaction of stearoyl-(1,N6)-etheno coenzyme A (stearoyl-epsilon-CoA) with acetyl coenzyme A carboxylase was investigated by using fluorescence spectroscopy. The fluorescence emission of stearoyl-epsilon-CoA was partially quenched by acetyl coenzyme A carboxylase. Analysis of the data for dissociation constant (KD) and the stoichiometry of the interaction (n) gave values of 5.06 nM and 1....

Hepatocytes were isolated from adult rats and cultured on a substratum of nylon mesh coated with rattail collagen (Sirica, A. E., Richards, W., Tsukada, Y., Sattler, C. A., and Pitot, H. C. (1979) Boc. N&Z. Acud. Sci. U. S. A. 76, 283-287). The addition of insulin (1 pM) to the culture medium increased ATP-citrate lyase activity 2.6-fold, whereas addition of glucagon (0.1 PM) decreased the acti...

We used a special-purpose glass microfiber sample, Johns-Manville Code 100/475, to study the effects of various acid and alkali treatments on biological activity as assessed by inflammation in the mouse peritoneal cavity, the leaching of Si, and the phase contrast optical microscopy (PCOM) fiber number. We used mild and medium treatments with oxalic acid and Tris buffer and harsh treatment with...

The medium composition was as follows : 0.15 M-sucrose, 30rn~-KCl, 1OmM-choline chloride, 10mM-succinate/Tris, lOmM-Tris/Mops, 3mM-P,/Tris, 2pM-rotenone, 0.1 mMEGTA and 2mg of rat-liver mitochondria/ml; pH7.4. Temperature 25°C. Respiration was stimulated by 0.5 m ~ ADP ( 0 ) in the presence of 1 mM-EDTA, by 20pmol of FCCP/mg (0 ) or by 6Opmol of FCCP/mg (0). When the respiration was stimulated ...

Purified inside-out photosystem II vesicles with retained capacity for oxygen evolution and a simple polypeptide composition were found to be more sensitive to washing with tris(hydroxymethyl)aminomethane (Tris) at alkaline pH than right-side out thylakoids. This suggests that the thylakoid membrane limits the penetration of the active unprotonated form of Tris. The inhibition of photosynthetic...

Lactobacillus casei ATCC 393 converted small amounts of citrate to diacetyl, other volatile compounds, and lipids. Citrate was accumulated passively by the organism. The presence of citrate in the growth medium decreased the uptake of acetate and its conversion to cellular lipids. Cells grown in citrate media contained more protein per cell than did controls. This increased protein content was ...

A new fluorometric assay for determining dipeptidyl peptidase IV (DPP IV; EC 3.4.14.5) was developed. The synthetic substrate glycyl-L-proline-4-methoxy-2-naphthylamide (20 mmol/L), Tris buffer (50 mmol/L, pH 8.3), and serum (20 microL) are mixed and incubated. The reaction is stopped with citrate (100 mmol/L, pH 4.0) and the released 4-methoxy-2-naphthylamine is measured fluorometrically. The ...

In this work, the molecular basis of aerobic citrate utilization by the gram-positive bacterium Corynebacterium glutamicum was studied. Genome analysis revealed the presence of two putative citrate transport systems. The permease encoded by citH belongs to the citrate-Mg(2+):H(+)/citrate-Ca(2+):H(+) symporter family, whereas the permease encoded by the tctCBA operon is a member of the tripartit...