Alterations in hepatic mixed-function oxidase activity of rainbow trout after acute treatment with polybrominated biphenyl isomers and FireMaster BP-6

The effects of FireMaster BP-6 and several pure isomers on hepatic microsomal mixed-function oxidase (MFO) activity in rainbow trout have been investigated. After one parenteral injection of these agents at 150 mg/kg and sacrifice 5 d later, there was no elevation of hepatic cytochrome P-450. The noncoplanar isomers 2,4,5,2',4',5'-hexa and 2,3,4,5,2',4',5'-heptabromobiphenyl did not increase any MFO activity generally associated with an increase in cytochrome P-450 levels, including the dealkylations of ethoxycoumarin and benzphetamine. The coplanar isomer 3,4,5,3',4',5'-hexabromobiphenyl produced an increase in O-deethylation of both ethoxycoumarin and ethoxyresorufin, suggesting enhancement of cytochrome P-448 associated activity, but produced no increase in benzphetamine N-dealkylation. The "mixed inducer" 2,4,5,3',4',5'-hexabromobiphenyl, produced a small but insignificant elevation of cytochrome P-448 associated MFO activities and no increase in cytochrome P-450 associated activities. At both 150 and 500 mg/kg, the commercial mixture of polybrominated biphenyls FireMaster BP-6 produced marked elevations of both ethoxycoumarin and ethoxy-resorufin dealkylations but had no effect on demethylation of benzphetamine. When microsomes from rainbow trout treated with FireMaster BP-6 were examined electrophoretically, A coomassie Blue-staining band at 57,000 daltons was intensified, as seen after treatment of fish with the cytochrome P-448 inducer beta-naphthoflavone. It is concluded that coplanar polybrominated isomers produce an induction of hepatic cytochrome P-448 associated activity, while noncoplanar isomers are ineffective as inducers of cytochrome P-450 related MFO activities in rainbow trout.     

Physiologic model for the pharmacokinetics of 2′deoxycoformycin in normal and leukemic mice

A flow-limited physiologic mathematical model has been developed to describe the time course of 2deoxycoformycin (2dCF) concentrations in the plasma and tissues of mice following iv and ip doses. Urinary excretion is modeled as a linear process involving filtration and secretion, since kidney clearance exceeded estimated glomerular filtration rate. Intracellular binding is described as the sum of linear nonspecific binding plus strong saturable binding to adenosine deaminase. Pharmacokinetic parameters are determined by a sequential optimization scheme in which each tissue is studied by means of a hybrid model. The model has been used to predict pharmacokinetic behaviour of 2dCF in both normal and leukemic mice, and model simulations are compared with published data.     

Microsurgical replantation of an incompletely amputated penis

The use of microvascular techniques in the replantation of one partially amputated penis is presented. The advantages of these techniques are discussed. A review of the literature is included; penis-replantation results prior to the introduction of microvascular techniques are compared to results achieved since the advent of these techniques. The superior results associated with microsurgical techniques are demonstrated, and it is concluded that microsurgical replantation is the procedure of choice in the repair of penis amputations.     

咪唑斯汀治疗慢性荨麻疹临床疗效评价及对血清IL-4水平的影响

目的：评价咪唑斯汀治疗慢性荨麻疹的疗效，探讨IL-4在慢性荨麻疹发病中的作用。方法：对32例慢性荨麻疹患用咪唑斯汀治疗，评价疗效，记录不良反应。同时用ELISA法检测慢性荨麻疹患治疗前后及正常人血清IL-4的水平。结果：治疗1、2wk后总有效率分别为62．5％、84．4％(P＜0．01)，不良反应3例。治疗前血清IL-4水平较正常人明显升高(P＜0．01)；治疗后IL-4水平下降(P＜0．01)，与正常人比较差异不甚明显(P＞0．05)。结论：咪唑斯汀是一种有效、安全的治疗慢性荨麻疹的药物，能降低慢性荨麻疹患血清IL-4的水平。     

Induction of hepatic phase II drug-metabolizing enzymes by 1,7-phenanthroline in rats is accompanied by induction of MRP3.

The purpose of the present study was to evaluate the effect of 1,7-phenanthroline (PH), which has been proposed to be a selective phase II enzyme inducer, on the gene expression of xenobiotic transporters, as well as hepatic and renal drug-metabolizing enzymes. After oral administration of PH for 3 days to male Sprague-Dawley rats, mRNA levels in liver (75 and 150 mg/kg doses) and kidney (75 mg/kg dose only) were determined using real-time quantitative polymerase chain reaction. At 150 mg/kg/day, PH treatment resulted in significant increases in hepatic mRNA levels of Mrp3 (36-fold), UGT1A6 (20-fold), UGT2B1 (4-fold), and quinone reductase (QR, 5-fold), compared with the vehicle-treated group. Similar increases in Mrp3 (99-fold), UGT1A6 (17-fold), UGT2B1 (3-fold), and QR (11-fold) mRNA levels were observed in the liver after PH treatment of rats at 75 mg/kg/day. In contrast, the expression levels of CYP2C11 and Oatp2 were decreased by approximately 80 and 50%, respectively. In addition, PH (75 mg/kg/day) elicited statistically significant changes in renal gene expression of CYP3A1, UGT1A6, QR, and Mrp3, but the magnitude of renal Mrp3 induction was less than 2-fold over control. Although PH is known to modulate hepatic glucuronidation in vivo, these data indicated that PH induced mRNA levels of the efflux transporter, Mrp3, which may also affect the disposition of xenobiotics.