Smoking rates among Rhode Island physicians: achieving a smoke-free society.

Over a 25-year period, regular surveys of physicians licensed in Rhode Island have recorded their smoking behavior. The six surveys show a decrease in the rate of cigarette smoking from 33% in 1963 to 4.6% in 1988. In the most recent survey, 65% of respondents reported never having smoked, and 87% of those who had ever smoked reported having quit. However, the statistic for the maximum number of cigarettes smoked regularly was higher for current smokers than for former smokers. Among physicians in the 1988 survey, most former smokers (85%) reported using only unassisted personal effort in quitting, whereas nearly half (48%) of current smokers tried methods involving assistance, such as self-help programs, group programs, or nicotine gum. Among former smokers who quit after 1983, the percentage trying assisted methods (34%) was closer to the percentage among current smokers. Apparently, remaining smokers include many heavy smokers who require more potent interventions in order to quit. Physicians in Rhode Island have almost become a smoke-free group. Their experience, coupled with their involvement in smoking prevention and cessation for their patients, can lead the rest of society on its path to becoming smoke-free.     

Immunoreactivity of an antibody to a beta/A4 sequence with Alzheimer paired helical filaments and tau protein.

beta/A4, a peptide that forms the extracellular amyloid fibrils of Alzheimer senile plaques, has also been proposed to be a component of Alzheimer paired helical filaments (PHFs). We compared BR88, an antiserum to amino acids 1-12 of beta/A4, with BR126, an antiserum to the sequence SEKLDFKDRVQS in tau protein, since tau protein is the only confirmed component of PHFs. In enzyme-linked immunosorbent assays (ELISAs), both antibodies reacted with pronase-treated PHFs better after PHFs were treated with guanidine. tau protein shares no sequence homology with beta/A4. Nevertheless, BR88 cross-reacted with human recombinant tau isoforms by ELISA and Western blot analysis with potencies comparable to those for anti-tau antibodies. BR88 reacted with a beta/A4 peptide as well on a molar basis as with tau protein and showed some reactivity to the tubulin-binding region of tau protein. In conclusion, the beta/A4 antiserum BR88 cross-reacts with tau protein, possibly explaining its reactivity with PHFs.     

Induction of FMLP-mediated calcium mobilization requires crosslinking of surface immunoglobulin in Daudi cells.

We have explored the requirements for the induction of the N-formyl-methionyl-leucyl-phenylalanine (FMLP) response in Daudi cells after anti-immunoglobulin treatment. Our results indicate that (a) induction of responsiveness to FMLP was observed in Daudi only after crosslinking of surface immunoglobulin by anti-immunoglobulin; (b) this induced responsiveness was not observed in Ramos or Wil-2 cells; (c) the F(ab')2 fragment was sufficient for the induction of the FMLP response, but the Fab fragment and the Fc fragment were ineffective; (d) of the many agents active in B lymphocyte regulation which were tested, none were as effective as anti-immunoglobulin in the induction of the FMLP response; and (e) three inhibitors of calcium mobilization (W-7 (N-(6-aminohexyl)-5-chloro-1-naphthalene sulfonamide), PMA (phorbol 12-myristate 13-acetate), and colchicine), acting on distinct mechanisms, inhibited both the calcium mobilization due to anti-immunoglobulin and the induction of responsiveness to FMLP. Our results suggest important determinants in the induction of a calcium-mobilizing FMLP response in cells of B lymphocyte lineage include (a) the cell type, (b) a selective requirement for activation via surface immunoglobulin, and (c) crosslinking of the surface immunoglobulin.     

Detection of liver fibrosis with magnetic cross-relaxation

The utility of MRI using magnetization transfer (MT) enhanced pulse sequences to diagnose hepatic cirrhosis in a rat model was investigated. Hepatic T₁ was measured with and without MT off-resonance RF pulses in 17 treated and six control rats. The livers were evaluated histologically, and the hydroxyproline content quantitatively measured. We did not find a statistically significant linear correlation between the MR relaxation times and the degree of tissue injury. However, the MR measurements performed with MT were superior to those without differentiating the treated and control groups. Specifically, the T₁ times were 695 ±76 ms for the treated group, versus 748 ± 61 ms in the controls; P= 0.095. The T_1sat times were also lower in the treated group, with statistical significance: 367 ± 51 ms versus 421 ± 38 ms, P = 0.016. Finally, the change in the relaxation rates (the inverse of the relaxation times) with and without saturation were 1.31 ± 0.22 s^?1 (treated group) versus 1.05 ± 0.12 s^?1 (controls), which differed significantly, P= 0.001.     

Natural history of vascular calcification in dialysis and transplant patients

Nephrol Dial Transplant 2004; 19: