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Understanding the interaction of local anesthetics (LAs) with plasma proteins is essential to understanding their systemic pharmacology and toxicology. The molecular determinants of LA binding to the major variant (F1*S) of human ␣ 1 -acid glycoprotein (AGP) were therefore investigated spectrofluorometrically using whole AGP and a novel, F1*S variant-selective probe previously developed in our laboratory. Equilibriumcompetitive displacement of this probe by LAs, observed by the recovery of AGP's fluorescence as the quenching probe was displaced from its high-affinity site, was characterized by inhibitory dissociation constants for the various LAs. The importance of electrostatic factors was assessed by examining the pH dependent binding of an ionizable LA, lidocaine, using the quaternary lidocaine derivative triethylammonium chloride] to control for pH dependent ionization of AGP. Uncharged lidocaine bound with at least 8 times the affinity of protonated lidocaine (K D ϭ 4.0 Ϯ 0.6 M and Ͼ32 M, respectively). This result is inconsistent with the current model of the AGP-binding site, which depicts a buried pocket having a negatively charged region that interacts with the amino termini of basic drugs. Consistent with the model, however, two sets of structurally homologous LAs (mepivacaine, ropivacaine, bupivacaine, and lidocaine, RAD-240, RAD-241, RAD-242, L-30, W-6603) demonstrated a strong positive correlation between hydrophobicity (measured as the octanol:buffer partition coefficient of the neutral species) and their free energies of dissociation. Given that the tertiary structure of AGP has proven refractory to resolution, these structure-activity studies should contribute to understanding the nature of the binding site on this important protein.Understanding the interaction of local anesthetics with plasma proteins is essential to predicting their systemic pharmacology and toxicology. Many basic drugs, including local anesthetics (LAs) and class I antiarrythmics, are bound in blood principally or in part by AGP (Routledge, 1986;Stanski and Watkins, 1986;Wood, 1986;Kremer et al., 1988). The binding of a drug to a plasma protein reduces its free fraction in serum, thus reducing its availability for active uptake or diffusion into surrounding tissue and significantly influencing its pharmacokinetics, toxicity, etc. (Wood, 1986).For example, the local anesthetic bupivacaine binds tightly to AGP (with K D ϭ 1 M) (Essassi et al., 1989), and this binding may mitigate the systemic toxicity of bupivacaine (Wulf et al., 1991;Mazoit et al., 1996).Indeed, altered pharmacokinetics have been observed following the binding of AGP to the LAs lidocaine and cocaine, and the same holds true with other clinically relevant amphipathic amines: amitriptyline, chlorpromazine, nicardipine, and verapamil (Benet and Hoener, 2002). For example, AGP concentration has been shown to correlate inversely with the free fraction of the LA ropivacaine 60 min after epidural injection (Porter et al., 2001). Also, one of the AGP variants...

It has been shown that cytomegalovirus (CMV) is present in coronary atherosclerotic plaques, but the clinical relevance of this presence remains to be elucidated. In this study we sought to examine CMV infection in atherosclerosis patients defined by different methods and to identify the clinical significance of CMV replication in the atherosclerotic plaques. The study included 105 consecutive patients who were admitted to our department and underwent coronary artery bypass grafting (CABG) surgical interventions. Coronary atherosclerotic specimens as well as 53 specimens from the mamillary artery of these same patients were analyzed. Enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) methods were used for evaluations. The CMV PCR test result was positive for 28 (26.7%) of patients with coronary artery atherosclerosis. After adjusting for other risk factors, coronary artery disease patients with a history of acute coronary syndrome were more likely to be positive for CMV PCR test (P = 0.027; odds ratio: 4.2; 95% CI: 1.18-15.0). They were also more likely to have a positive family history for cardiovascular diseases (CVD). This study confirms previous evidence about the replication of CMV virus in the atherosclerotic plaques of coronary arteries and brings clinical significance to this observation by showing a higher prevalence of acute coronary syndromes in those patients with CMV-infected plaques. Our study also suggests a familial vulnerability to CMV replication in the coronary artery walls.

In contrast with previous reports from other countries, this study of Iranian national data revealed that in Iran, most related and unrelated living kidney donors are male and the percentage of recipients who are female exceeds the percentage of donors who are female. Considering previous reports from other countries, our findings suggest that Iran is the only country in which females are more likely to be recipients of a kidney allograft than donors. The reason for the predominance of male kidney donors in Iran is probably multifactorial and associated with economical, social and cultural issues. The financial incentives paid to living unrelated donors may be an attraction for males to donate a kidney although, even in living related donations, males constitute the majority of donors.

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Liver transplant patients exhibiting early deterioration of graft function or other hepatic symptoms should, in addition to assessment for rejection, be evaluated for H-PTLD. In addition, all H-PTLD patients should be evaluated for bone marrow involvement, especially if they are EBV positive. Prospective studies with large patient populations are needed to confirm our results.

Older renal transplant patients are at increased risk for development of very late onset PTLD, and should be strictly followed. further multi-institutional prospective studies are needed to confirm our results.