Immunohistochemical localization and dynamics of paraquat in the stomach and esophagus of rats

Summary The dynamics of paraquat in the stomach and esophagus of rats were demonstrated using immunohistochemical techniques. The Rats were killed 3 h, 12 h, 24 h, 3 days, 7 days and 10 days after intravenous administration of paraquat. In the stomach, paraquat was localized in the epithelial cells between 24h and 10 days after injection, whereas in the esophagus, paraquat was localized in epithelial cells and the lamina propria mucosa between 12 h and 10 days after administration. Although these findings were similar to those observed in the intestine of rats, no clear changes in the distribution of paraquat with time were observed; suggesting that the stomach and esophagus are important reservoirs for the redistribution of paraquat.     

Video-assisted thoracoscopic wedge resection of solitary pulmonary metastasis from hepatocellular carcinoma

We report a metastatic pulmonary tumor resected by video-assisted thoracoscopic surgery. A 63-year-old female was found to have four nodules of hepatocellular carcinoma (HCC) in January 1991; after non-surgical treatment, the tumors had become necrotic. In June 1992, a new HCC nodule was found. After infusion chemotherapy, it became necrotic. In September 1993, a solitary lung tumor, 2.4 cm in diameter, appeared at the periphery of the right lung. Because the tumor was considered to be a metastatic HCC rather than a primary lung cancer, it was removed by thoracoscopic wedge resection. Although whether metastasectomy contributes to prolongation of survival is still controversial, thoracoscopic pulmonary resection may be indicated for solitary peripheral metastasis, if the primary HCC is well controlled by multidisciplinary treatment.     

Spondylolysis after posterior decompression of the lumbar spine: 35 patients followed for 3-9 years

Radiographs were examined in 35 patients who had had posterior decompression without fusion of the lumbar spine. Spondylolysis was found in 10 patients. Segmental range of motion, degree of vertebral slippage and width of decompression were analyzed by radiography. There was greater vertebral slippage after surgery in patients with postoperative spondylolysis than in those without spondylolysis. We conclude that excessive bony decompression may cause postoperative spondylolysis.     

Differing time courses between Δlactate and mitochondrial respiration during coronary occlusion and after reperfusion in canine hearts

Summary The present study was designed to clarify whether or not a difference between arterial and venous lactate (lactate) levels is useful for evaluation of mitochondrial function in ischemia-reperfused myocardium. In the first experiment, 12 dogs were divided into 2 groups: 10-min occlusion of the left anterior descending coronary artery (LAD) followed by 10-min reperfusion, or 30-min occlusion followed by 40-min reperfusion, were performed. The lactate levels in the femoral artery and the great cardiac vein were measured enzymatically. Lactate was reversed immediately after occlusion. Ten min and 20 min were required for the recovery of lactate in the 10-min-occlusion with 10-min-reperfusion, and 30-min-occlusion with 40-min-reperfusion groups, respectively. In the second experiment, 36 dogs were divided into 6 groups: 10-min occlusion of LAD; 10-min occlusion with 10-min reperfusion; 30-min occlusion; and 30-min occlusion with 10-, 20-, or 40-min reperfusion were performed. Mitochondria from normal and occluded or reperfused areas were prepared, and the respiratory function of the mitochondria was measured polarographically. No significant decreases in the mitochondrial function were observed in the 10-min-occlusion, and 10-min-occlusion with 10-min-reperfusion groups. On the other hand, respiratory function of mitochondria was impaired by 30-min occlusion and was not improved by 10- or 20-min reperfusion. Significant recovery in the mitochondrial function was observed after 40-min reperfusion. That is, differing recovery time courses between lactate and the mitochondrial function were observed.     

Analgesic dose-response relation in cervical epidural block

The relationship between the age and the spread of analgesia from different epidural anesthetic doses was examined by studying analgesic dose responses in cervical epidural analgesia. Two different anesthetic doses (5ml or 10ml) of 2% mepivacaine were injected into the cervical epidural space at a constant pressure (80mmHg) using an intravenous apparatus, and the spread of analgesia to pinprick was assessed. The significant correlation was found between the patients age and the number of spinal segments blocked (5ml:r = 0.8498, P < 0.01, 10ml:r = 0.5988, P < 0.01). The inverse linear relationship was found between the patients age and the segmental dose requirement (5ml:r = –0.6754, P < 0.01, 10ml:r = –0.5784, P < 0.01). Patients under 39 years of age showed a direct relationship between the dose injected and the number of spinal segments blocked, enabling prediction of the number of segments blocked with a given dose of local anesthetic. Doubling the epidural dose approximately doubled the number of spinal segments blocked. The analgesic dose-response relation in patients over 60 years of age differed from that in patients under 39 years of age and doubling the epidural dose did not double the number of spinal segments blocked. Progressively more extensive analgesia was obtained from a given dose of local anesthetic with advancing age. It was difficult to limit the extent of analgesia by injecting a smaller dose of local anaesthetic in the elderly.(Hirabayashi Y, Matsuda I, Inoue S et al.: Analgesic dose-response relation in cervical epidural block. J Anesth 2: 22–27, 1988)     

Adriamycin-Lipiodol suspension for i. a. chemotherapy of hepatocellular carcinoma

Summary Physicochemical properties of two types of adriamycin preparation, suspensions and emulsions prepared for i.a. chemotherapy of hepatocellular cacinoma, were investigated. A suspension was prepared by dispersing adriamycin directly into the lipid contrast medium, Lipiodol, whereas an emulsion was obtained by emulsifying an aqueous solution of adriamycin into Lipiodol. The dispersibility of the drug in each preparation was examined microscopically. The chemical stability of and drug release from the preparation were determined by high-performance liquid chromatography and spectrophotometry, respectively. The suspension was then given to ten patients with primary hepatocellular carcinoma. The suspension maintained good dispersibility without coagulation of drug particles, whereas coalescence of aqueous droplets and the resultant phase separation occurred 4 h after preparation of the emulsion. Both preparations maintained the initial drug content for at least 1 week at room temperature. The release of adriamycin was more prolonged in the suspension than in the emulsion. After i.a. administration of the suspension, a selective accumulation of Lipiodol in the tumor and decrease in serum -fetoprotein (AFP) levels were found in most patients. A significant amount of adriamycin was still detected in hepatic speciments resected from two patients 1 and 2 months after treatment. These findings suggest that the adriamycin-Lipiodol suspension may be a useful preparation for targeting chemotherapy to hepatocellular carcinoma.     

Comparative uptake and retention of adriamycin andN-benzyladriamycin-14-valerate in human CEM leukemic lymphocyte cell cultures

Summary N-Benzyladriamycin-14-valerate (AD 198) is a new lipophilic adriamycin (ADR) analogue that shows marked therapeutic superiority to ADR in murine tumor model systems yet differs mechanistically from ADR in a number of ways. Among its other properties, AD 198 produces a delayed but profound effect on cell-cycle progression and a pattern of continuing DNA damage in cultured cells briefly exposed to the drug. Using radiolabeled drug forms and radioassays combined with HPLC separation and fluorimetric detection techniques, aspects of drug accumulation, biotransformation, and retention in cultured human CEM leukemic lymphocytes were studied, in part to determine a possible pharmacologic basis for the latent effects seen with this drug. In addition, the cellular pharmacology of AD 198 and ADR were comparatively examined under identical experimental conditions. When CEM cells were incubated with drug at equi-growth inhibitory/minimally cytotoxic concentrations (AD 198, 1.0 M; ADR, 0.1 M), a number of differences were apparent. Under conditions of continuous 24-h drug exposure, a slow cellular accumulation and equilibration was observed with ADR (cell: medium equilibrium, 1:11 after 4–6 h), whereas the uptake of AD 198 was rapid and extensive (cell: medium equilibrium, 3:1 within 30 min). In drug-retention studies, when cells were pretreated at the same drug concentrations as before (AD 198 for 1 h; ADR for 4 h) and then transferred to drug-free media, both compounds re-equilibrated their intracellular drug content with the fresh media, losing about 50% of their respective anthracycline levels. Liquid chromatographic analysis of ADR-treated cultures under both sets of conditions showed the parent drug to be the only intracellular anthracycline species, whereas analysis of AD 198-treated cultures revealed two fluorescent signals corresponding to the parent drug and its 14-deesterified biotransformation product,N-benzyladriamycin (AD 288). Levels of AD 288 rose from 2% of the total intracellular anthracycline content immediately on drug admixture to 61% following 24 h continuous drug exposure and to 69% at 24 h in cells exposed to drug for 1 h and then continued in drug-free media for 24 h. At all times, the balance of the intracellular anthracycline fluorescence was attributable to the parent drug; no ADR was detectable in AD 198-treated cells by either fluorescence detection or radioassay. Thus, AD 198 is not a prodrug form of ADR, and the in vitro effects of this agent, including the latent effects on cell-cycle inhibition and DNA damage seen in cells following short-term drug exposure, can be explained on the basis of the high levels of active parent drug and biotransformation product that accumulate and persist in the cells.Abbreviations ADR adriamycin (doxorubicin) - AD 198 N-benzyladriamycin-14-valerate - AD 288 N-benzyladriamycin - AD 32 N-trifluoroacetyladriamycin-14-valerate - AD 143 N-trifluoroacetyladriamycin-14-0-hemiadipate - AD 41 N-trifluoroacetyladriamycin - [¹⁴C]-AD 198 [benzyl]--methylene-¹⁴C]-N-benzyladriamycin-14-valerate - [¹⁴C]-ADR [14-¹⁴C]-adriamycin - HPLC high-performance liquid chromatography - TLC thin-layer chromatography - DMSO dimethylsulfoxide - S-MEM Eagle's minimum essential medium for suspension culture - PBS phosphate-buffered saline (pH 7.0)     

In vivo activity on murine tumors of a novel antitumor compound,N-β-dimethylaminoethyl 9-carboxy-5-hydroxy-10-methoxybenzo[a]phenazine-6-carboxamide sodium salt (NC-190)

Summary A novel antitumor compound, N--dimethylaminoethyl 9-carboxy-5-hydroxy-10-methoxybenzo[a]-phenazine-6-carboxamide sodium salt (NC-190) was evaluated for its antitumor activity in experimental murine tumor systems. In the initial studies with P388 leukemia (i.p.-i.p.), NC-190 led to an increase of >200% in life span (ILS), and 75% of the mice were alive on day 30, when the optimal dose (50 mg/kg, days 1–5) was given. Additionally, the compound had significant activities against i.p. inoculated mouse L1210 leukemia, B16 melanoma, M5076 reticulum cell sarcoma, sarcoma 180, mouse hepatoma MH134, and rat Yoshida sarcoma and Yoshida ascites hepatoma AH130. The optimal dose resulted in a >280% ILS with a 30-day survival of 50% in mice with L1210 leukemia (100 mg/kg, days 1–5), a 156% ILS in mice with B16 melanoma (50 mg/kg, days 1–5), a 98% ILS with a 90-day survival of 25% in mice with M5076 reticulum cell sarcoma (25 mg/kg, days 1, 5, 9, and 13), a >300% ILS with a 60-day survival of 50% in mice with sarcoma 180 (50 mg/kg, days 3–10), a 148% ILS with a 60-day survival of 25% in mice with MH134 (25 mg/kg, days 1–5), a 129% ILS with a 60-day survival of 12.5% in rats with Yoshida sarcoma (12.5 mg/kg, day 3–10), and a >161% ILS with a 60-day survival of 50% in rats with AH130 (6.3 mg/kg, days 3–10). In the experiments with s.c. inoculated tumors, NC-190 not only inhibited tumor growth, but also increased the life span of mice with Lewis lung carcinoma or B16 melanoma. The 60-day survivors accounted for 60% and 30% in mice with Lewis lung carcinoma and B16 melanoma, respectively. The compound significantly inhibited the spontaneous lung metastasis of Lewis lung carcinoma by more than 90% when eight daily i.v. injections were given. NC-190 was active by the i.p., s.c., and i.v. routes. Five consecutive daily i.p. doses (days 1–5) were more effective than a single dose (day 1), two doses (days 1 and 5), or three doses (days 1, 5, and 9). NC-190 warrants further study as a potential antineoplastic agent against human neoplasms, as it has a broad spectrum of antitumor activity and inhibits metastasis.Abbreviations ILS increase in life span - MST median survival time - MMC mitomycin C - ADM adriamycin - CPA cyclophosphamide - 5-FU 5-fluorouracil     

Discrete breakpoint mapping and shortest region of overlap of chromosome arm 1q gain and 1p loss in human hepatocellular carcinoma detected by semiquantitative microsatellite analysis

Recurrent chromosomal gain at 1q is one of the most common features of human hepatocellular carcinoma (HCC), but how the gain at 1q contributes to hepatocarcinogenesis is still unclear. To identify the target genes, precise determination of the shortest region of overlap (SRO) and of breakpoints is necessary. Similarly, the role of loss at 1p, which is also a major cytogenetic aberration in HCC, needs to be determined. Fifty HCCs were examined with the aid of 59 microsatellite markers distributed throughout both arms of chromosome 1. To detect allelic gain effectively, the cutoff value of the allelic imbalance index was set at 0.70. Alleles showing imbalance were subjected to multiplex PCR, using a retained allele as an internal control, to determine whether the imbalance was the result of chromosomal gain or loss. The SRO of the gains was defined as D1S2878-D1S2619 (1q23.-q25.3, 16.9 Mb), which involved 36 cases (72%). Gains in the number of copies of certain oncogenes within this region seemed to be critical for the pathogenesis of HCC. In contrast, the centromeric breakpoints of these gains varied, but they tended to occur mainly in the pericentromeric region (26 of 50 cases, 52%). Rearrangement of specific genes associated with the gains is unlikely. On the other hand, the SRO of deletion was defined as D1S2893-D1S450 (1p36.32-p36.22, 5.1 Mb). Four known putative tumor-suppressor genes (TP73, RIZ1, NBL1/DAN, and CDKN2C) were outside the SRO, suggesting the presence of other candidate genes with critical roles in hepatocarcinogenesis.     

Differential expression of human beta-defensin 2 in keratinized and non-keratinized oral epithelial lesions; immunohistochemistry and in situ hybridization

Human beta-defensin(hBD)-2, an antimicrobial peptide, is produced by various epithelial cells. Because hBD-2 expression in the oral epithelium has not been assessed, we investigated its localization in normal oral epithelium and epithelial lesions. hBD-2 expression was studied using immunohistochemistry and in situ hybridization on formalin-fixed, paraffin-embedded tissue sections from 30 cases of squamous cell carcinoma and 6 cases of leukoplakia. Immunostaining for hBD-2 was more intense in hyperkeratinized than in ortho- or non-keratinized epithelium. In contrast, signals for hBD-2 mRNA were frequently stronger in non-keratinized epithelium than in hyper- or ortho-keratinized epithelium. The results suggest that keratinization in oral epithelium plays an important role in the biological function of hBD-2 both at the mRNA level and in the retention of the peptide in the epithelium.