The interaction of bovine serum albumin (BSA) with cationic surfactant cetylpyridinium bromide (CPB) in aqueous solution (pH 7.00) was studied quantitatively with ultraviolet (UV)-visible, far-UV, and near-UV circular dichroism, fluorescence, small angle x-ray scattering, and nuclear magnetic resonance measurement. It was found that CPB at low and high concentrations could induce the unfolding and refolding of BSA, respectively. We suggest that in the unfolding process, there existed BSA-CPB complex with the "necklace and bead" structure in which the unfolded BSA wrapped around CPB micelles, and that the hydrophobic interaction between the complexes led to the formation of large aggregates. The aromatic headgroup of CPB interacted with the tryptophan residues of BSA, resulting in the aromatic ring stacking between BSA and CPB. During the refolding process, the BSA molecule was penetrated into the rod micelle of CPB and the hydrophobic moiety of the BSA molecule was exposed outside while its hydrophilic part was hidden inside, thereby disrupting the aromatic ring stacking.

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Angiotensin II (Ang II) has been recognized as an apoptosis inducer in podocytes, but the mechanism of apoptosis induced by Ang II is unclear. Transient receptor potential cation channel 6 (TRPC6) is a calcium channel located in podocyte membrane. The present study evaluated the alteration of TRPC6 expression and the Ca(2+) influx involved in Ang II-induced podocyte apoptosis. The possible pathways related to TRPC6 in Ang II-induced podocyte apoptosis were also investigated. The apoptosis of mouse podocytes (MPC5) was induced by Ang II. The protein level of TRPC6 was increased markedly in response to Ang II stimulation, and the intracellular Ca(2+) concentration was elevated. By transfection with TRPC6 siRNA, Ang II-induced podocyte apoptosis and the transient Ca(2+) influx were inhibited. Treated with extracellular signal-regulated kinase (ERK) pathway specific inhibitor U0126 or nuclear factor-kappaB (NF-kappaB) pathway specific inhibitor ammonium pyrrolidinedithiocarbamate (PDTC) and Ang II, respectively in podocytes, not only was the TRPC6 up-regulation reduced, but the podocyte apoptosis was also decreased. Moreover, the translocation of NF-kappaB in nucleus resulted from Ang II was reduced by treatment with U0126. In conclusion, the enhancement expression of TRPC6 as well as the increased Ca(2+) influx mediated by TRPC6 channels contributed to the podocyte apoptosis. The activation of ERK pathway and subsequent translocation of NF-kappaB was possibly necessary for the up-regulation TRPC6 induced by Ang II.

The hypothesis that endothelium-derived relaxing factor (EDRF) modulates hypoxic pulmonary vasoconstriction (HPV) was tested in isolated, blood-perfused rat lungs ventilated with gas mixtures of 21% O2-5% CO2-74% N2 (normoxia) or of 3% O2-5% CO2-92% N2 (hypoxia); 30 microM NG-monomethyl-L-arginine (L-NMMA), an inhibitor of EDRF production, caused a reduction in the endothelium-dependent relaxant response to acetylcholine (ACh) from 62 +/- 7, 88 +/- 4, and 100 +/- 4% to 26 +/- 8, 49 +/- 12, and 75 +/- 7% at ACh concentrations of 1, 10, and 100 microM, respectively (p less than 0.05 at all concentrations), indicating that L-NMMA acts via the inhibition of EDRF production. L-NMMA induced a concentration-related augmentation in HPV of 20 +/- 5, 32 +/- 8, and 34 +/- 8% at concentrations of 30, 300, and 1,000 microM (p less than 0.05, compared with a vehicle control group at all concentrations). The pressor response to a dose of angiotensin II (A-II), which produced the same increase in pulmonary artery pressure as that induced by hypoxia, was also significantly augmented (2 +/- 0.6%), but to a lesser extent. The augmentation of HPV by 30 microM L-NMMA was completely reversed by 1 mM L-arginine (a precursor of EDRF), but not by D-arginine (an isomer of L-arginine). One and 6 mM L-arginine, but not 6 mM D-arginine caused a significant inhibition of HPV by 20 +/- 2 and 47 +/- 12% (p less than 0.05, compared with the vehicle control group) and a small but not significant reduction in A-II-mediated contraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Objective.To evaluate the longterm safety of adalimumab administered with or without methotrexate (MTX) and compare the efficacy of combination therapy initialization to adalimumab or MTX monotherapy initialization during the open-label extension (OLE) of the PREMIER trial (ClinicalTrials.gov Identifier:NCT00195663).Methods.Patients with early rheumatoid arthritis (RA) were randomized to receive blinded adalimumab + MTX, adalimumab alone, or MTX alone for 2 years. Following the double-blinded period, patients enrolling in the OLE were given adalimumab for up to 8 additional years, beginning as monotherapy; investigators could add MTX at their discretion. Results for clinical, functional, and radiographic progression were collected for up to 10 years of treatment.Results.During the PREMIER OLE, 250/497 patients (50.3%) completed the trial without new safety signals arising. Similar proportions of patients discontinued the trial early, although lack of efficacy was reported less often for patients initially randomized to the adalimumab + MTX arm (9.3%; 21.2%, and 23.7% for adalimumab and MTX monotherapies, respectively). Clinical and functional disease control was maintained throughout the trial. Patients initially randomized to adalimumab + MTX displayed better outcomes, particularly in prevention of radiographic progression (modified total Sharp score change = 4.0, 8.8, 11.0 at Year 10 for the initial adalimumab + MTX, adalimumab, and MTX arms, respectively).Conclusion.Intensive therapy with adalimumab + MTX combination in patients with early RA has longterm benefits compared to patients initiating with 2-year adalimumab or MTX monotherapy that persists up to 10 years following adalimumab OLE. No new safety findings were observed following longterm adalimumab treatment.