Phase I and pharmacologic study of oral (E)-2′-deoxy-2′-(fluoromethylene) cytidine: on a daily × 5-day schedule

(E)-2-deoxy-2-(fluoromethylene)cytidine (FMdC), one of the most potent inhibitors of ribonucleoside diphosphate reductase, was selected for clinical development because of its novel mechanisms of action, and strong antitumor activity against experimental tumor models. This study was designed to determine the toxicities, maximum-tolerated dose (MTD), and pharmacokinetic profile of FMdC. FMdC was given orally for 5 consecutive days every 3 or 4 weeks in patients with advanced solid tumors. The starting dose was 8 mg/m2/day. Pharmacokinetic studies were carried out on days 1 through 5 of the first cycle. Ten patients with non-small cell lung cancer received 15 courses of FMdC at doses which were de-escalated from 8 mg/m2/day to 2 mg/m2/day because of unexpected severe toxicities at the starting dose level. Neutropenia was the dose-limiting toxicity. Thrombocytopenia and anemia were mild. Flu-like symptoms and fever were the common non-hematologic toxicities. The MTD was 4 mg/m2/day, since four of six patients developed grade 3–4 neutropenia. At the 4 mg/m2/day dose level, the mean terminal half-life, maximum plasma concentration (Cmax), plasma clearance, and mean residence time on day 1 were 3.20 h, 15.8 ng/ml, 2.91 l/h/kg, and 4.03 h, respectively. The recommended dose for phase II studies with this schedule is also 4 mg/m2/day for 5 days. Further investigations are necessary to establish optimal dosing schedules and routes for the administration of FMdC.     

E. coli endotoxin enhances cardiomyopathy in rats with chronic alcohol consumption

The purpose of the study was to show whether it was possible to produce alcoholic cardiomyopathy by short-term alcohol ingestion combined with an infinitesimally low endotoxin injection. Wistar rats were fed an alcoholic liquid diet according to the formula of Lieber and Decarli, and challenged with an injection ofE. coli lipopolysaccharide (LPS) endotoxin (1.0 g/g body weight per day for ten weeks). After ten weeks alcohol diet combined with LPS challenge, light microscopical examination showed changes commonly seen in alcoholic cardiomyopathy such as hypertrophy, oedema and disarray of myofibers. By electron microscopy, degeneration of mitochondria and degeneration of myocardial fibers were observed, the latter showing disturbance of the myofibrilla arrangement and interstitial fibrosis. Rats on an alcoholic liquid diet and rats challenged with a single identical doses of LPS did not show characteristic histological findings of alcoholic cardiomyopathy. These results suggest that short-term alcohol ingestion combined with an infinitesimally low endotoxin injection experimentally produces alcoholic cardiomyopathy, and may support the idea that endotoxin plays an important role in the aetiology of alcoholic cardiomyopathy.     

Radiation tolerance of the cochlear nerve at the γ-knife in rabbits

Since the first treatment of acoustic neurinoma using the γ-knife by Leksell, a series of cases have been reported with good control rates. However, the most frequent complication is delayed hearing loss which occurs in more than 50% of patients. The purpose of this study was to define a safe dose by analyzing the radiosurgical dose-response relationship and histological effects on the normal cochlear nerve in rabbit. The rabbits had computed tomography (CT)-guided stereotactic radiosurgery on their cochlear nerves in the internal auditory canal with a 4 mm collimator focusing of a γ-unit. Maximum doses of 10, 20, 30, 40, 60, 80, 100, 200 and 500 Gy were administered. After the radiosurgery, auditory brain stem responses (ABR) and the behavior of the rabbits were evaluated periodically. At the conclusion, histological investigations were performed. No physiological or histological findings were observed from doses of 30 Gy or below during the 12 month period after the radiosurgery. A dose of 100 Gy caused a severe ABR threshold elevation, vestibular dysfunction and facial palsy. Necrosis and demyelination of nerves were observed pathologically. In this study, we determined that the safe dose to the normal cochlear nerve during radiosurgery was under 40 Gy in rabbits, and complications seemed to vary due to individual differences in radiation tolerance.     

A lethal osteochondrodysplasia with mesomelic brachymelia, round pelvis, and congenital hepatic fibrosis: two siblings born to consanguineous parents

We report a hitherto unknown, lethal osteochondrodysplasia in two Japanese siblings born to consanguineous parents. The skeletal abnormalities are characterised by mesomelic brachymelia with bowed forearms, a round pelvis with shortened greater sciatic notches, an ossification defect of the pubic bones, and absence of ossification centers in the cervical vertebral bodies. The associated visceral anomalies comprised periportal fibrosis and cystic dysplasia of the intrahepatic bile ducts, pancreatic ductal ectasia, a simple renal cyst, microcephaly with multifocal laminar necrosis and ectopic gray matter, dysplastic tracheobronchial cartilage, abnormal lobulation of the lung, diaphragmatic hernia, and stenotic pulmonary valve. Thrombocytopenia was present but megakaryocytes were slightly increased in the bone marrow. The patients showed various dysmorphic features including aniridia, a long palpebral fissure, prominent nasal bridge, beaked nose, flat philtrum, low-set fleshy ears, micrognathia with submucosal cleft palate, and multiple joint contractures. Received: 23 May 1997 Accepted: 27 June 1997     

Expression of apoptosis-related proteins in adenomyotic uteri treated with danazol and GnRH agonists.

The biologic properties of adenomyosis and the effects of therapeutic agents on adenomyosis were evaluated with immunohistochemistry, terminal deoxy-nucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method, transmission electron microscopy, and analysis of genomic abnormality. In the adenomyotic endometrium, estrogen receptor (ER) expression was more intense than in the eutopic endometrium during the secretory phase, and bcl-2 was constantly expressed throughout the menstrual cycle. The expression of ER and bcl-2 was weaker in the adenomyotic endometrium treated with danazol than in that treated with gonadotro-pin-releasing hormone agonist (GnRHa), whereas bcl-2 phosphorylated on serine-87 was more intensely expressed in danazol-treated adenomyotic endometrium than in the GnRHa-treated one. The number of TUNEL-positive cells increased in the adenomyotic endometrium treated with danazol or GnRHa. Ultrastructurally, most of the adenomyotic endometrial cells treated with danazol underwent postapoptotic necrosis and formed a cluster of dead cells. In contrast, cells treated with GnRHa underwent typical apoptosis and were sparsely distributed in the adenomyotic endometrium. Analysis of several cancer-related genes showed no microsatellite instability or loss of heterozygosity in adenomyotic tissues. Therefore, we conclude that the occurrence of adenomyosis is correlated to bcl-2 expression regulated by estrogen and ER rather than genetic mutation.     

Caffeine induces apoptosis of human umbilical vein endothelial cells through the caspase-9 pathway.

Caffeine is known to modulate placental and fetal umbilical circulation. It is demonstrated that apoptosis of human umbilical vein endothelial cells (HUVECs) is associated with placental umbilical vascular diseases. The present study was conducted to investigate the effects of caffeine on apoptosis of HUVECs. Isolated HUVECs were cultured under serum-free conditions for 24 h, and then treated with graded concentrations of caffeine (30, 100 and 300 microM) for additional 24 h and 48 h. The number of viable HUVECs was determined by cell counting. Apoptotic HUVECs were assessed by Hoechst33342 dye staining. The expression of caspase-9, caspase-8, caspase-3 and poly(ADP-ribose) polymerase (PARP) was assessed by Western blot analysis. Caffeine induced a dose- and time-dependent decrease in the number of viable HUVECs. Caffeine at concentrations higher than 100 microM significantly increased the percentage of apoptotic HUVECs. Caffeine at concentrations higher than 100 microM significantly increased cleaved caspase-9, caspase-3 and PARP expression in HUVECs at 24-h treatment compared with untreated cultures, whereas 30 microM caffeine significantly increased only caspase-3 expression at 24 h. Caffeine did not affect cleaved caspase-8 expression at 48 h. These results suggest that high concentrations of caffeine inhibit cell growth of HUVECs and induce apoptosis through the caspase-9 pathway.