Prenatal diagnosis of fetal complete atrioventricular block with QT prolongation and alternating ventricular pacemakers using multi-channel magnetocardiography and current-arrow maps

We report a case of fetal complete atrioventricular block (CAVB) with QT prolongation and alternating ventricular pacemakers diagnosed by magentocardiography (MCG). Fetal bradyarrhythmia of around 60 bpm was detected at 30 weeks of gestation. Ultrasonography revealed fetal CAVB without structural cardiac anomalies. MCG was recorded at 30 weeks of gestation using a 64-channel superconducting quantum interference device (MC-6400, Hitachi, Japan). The averaged MCG revealed QT prolongation, and the current-arrow maps generated by MCG revealed alternating ventricular pacemakers. The diagnosis was confirmed by electrocardiogram after birth. A permanent pacemaker was implanted during the early neonatal period, and the infant was healthy at 6 months of follow-up. MCG may be a useful diagnostic tool for fetal CAVB with QT prolongation and alternating ventricular pacemakers.     

Vasopressin receptor knockout mice as an animal model of psychiatric disorders]

Arginine vasopressin (AVP) is a neurohypophyseal peptide best known as an antidiuretic hormone. AVP receptors have been classified into three subtypes: V1a, V1b, and V2 receptors. The V1a receptor (V1aR) and V1b receptor (V1bR) are widely distributed in the central nervous system, including the cortex and hippocampus. In the present study, we examined the performance of V1aR or V1bR knockout (KO) mice compared to wild-type (WT) mice in behavioral tests. V1aR KO mice exhibited impairments of spatial learning (eight-arm radial maze), prepulse inhibition (PPI) and social behavior in comparison to WT mice. On the other hand, V1bR KO mice also displayed impairments of PPI and social behavior. These results suggest that V1aR and V1bR may be involved in psychiatric disorders associated with impairments of sensorimotor gating and social behavior such as schizophrenia and autism.     

Antitumor activity of cis-diamminedichloroplatinum (II) depends on its time × concentration product against human gastric cancer cell lines in vitro

A pharmacodynamic study of cisplatin (DDP) was conducted using the gastric cancer cell lines MKN-45 and MKN-74 in vitro. Ten thousand tumor cells were incubated with 0.4–500 μg/ml DDP for 1–25 h, followed by recovery culture for a further 48 h. At the end of incubation, cell viability was detected by the MTT end-point, and the inhibition rate was compared in relation to the incubation time, DDP concentration, and the time × concentration product (area under the curve in vitro: AUC vitro). In both of the cell lines, the IC50 and IC90 values decreased as the exposure time increased, going a linear curve with a slope of almost — 1, and showing a typical log-log AUC vitro-dependent curve. These results indicate that the antitumor activity of DDP is dependent on its AUC vitro, suggesting the clinical usefulness of this drug when administered daily in small divided doses. © 1995 Wiley-Liss, Inc.     

Reduced Activity of Anabolizing Enzymes in 5-Fluorouracil-resistant Human Stomach Cancer Cells

The mechanism of resistance to 5-fluorouracil (5-FU) was studied with NUGC-3/5FU/L, a human stomach cancer cell line which had acquired resistance as a consequence of repeated 5-day exposures to stepwise-increasing concentrations of 5-FU in vitro . NUGC-3/5FU/L was 200-fold and over 16-fold resistant to 96-h and 1-h exposures to 5-FU, respectively. NUGC-3/5FU/L incorporated less 5-FU into RNA, indicating resistance to the RNA-directed action of 5-FU. On the other hand, NUGC-3/5FU/L also showed resistance to in situ thymidylate synthase (TS) inhibition by 5-FU. Polymerase chain reaction-single-strand conformation polymorphism analysis of TS cDNA and a FdUMP ligand binding assay showed that quantitative and qualitative alterations of TS are not responsible for this resistance. In contrast, the ability to metabolize 5-FU to its active metabolites, FUTP and FdUMP, was reduced in NUGC-3/5FU/L. We found that not only the activities of uridine phosphorylase/kinase and orotate phosphoribosyl-transferase (OPRT), but also the level of phosphoribosyl pyrophosphate, a cosubstrate for OPRT, were significantly lower in NUGC-3/5FU/L than in the parent NUGC-3. These results indicated that resistance to 5-FU in NUGC-3/5FU/L is due to reduced activities of 5-FU-anabolizing enzymes, but not to an alteration of TS. 2'-Deoxyinosine effectively enhanced TS inhibition by 5-FU in the resistant cells, thus markedly sensitizing them to 5-FU.     

Role of macrophage inflammatory protein 2 in acute lung injury in murine peritonitis

BACKGROUND: Acute lung injury is a frequent extraabdominal complication of bacterial peritonitis, and neutrophil plays an important role in this lung damage. Macrophage inflammatory protein 2 (MIP-2) serves the same chemotactic function as IL-8 which is a potent neutrophil chemotactic factor in humans, and we investigated the role of MIP-2 associated with neutrophil recruitment in the lung of murine peritonitis. METHODS: Cecal ligation and puncture (CLP) were performed on mice. MIP-2 levels in blood and lung tissue, MIP-2 mRNA expression in lung tissue and bronchoalveolar lavage fluid (BALF), and CD11b expression on peripheral blood neutrophil and BALF cells were determined after CLP. In addition, we investigated the effect of anti-MIP-2 antibody on the lung injury associated with peritonitis. RESULTS: MIP-2 mRNA expression was observed in lung tissue after CLP and numerous neutrophils were accumulated in the lung under those conditions. Anti-MIP-2 antibody contributed to the inhibition of the CD11b expression and chemotaxis of pulmonary neutrophils, lung edema, and thus the reduction in peritonitis-related mortality. CONCLUSIONS: MIP-2 plays a pivotal role in neutrophil recruitment in the lung following peritonitis, and control of neutrophil accumulation in the lung by neutralizing MIP-2 is recommended as a new therapeutic approach to the lung damage associated with peritonitis.     

A case of postoperative palsy of the brachial plexus and facial nerve caused by use of cervical collar during lung surgery

We report a case of palsy of the brachial plexus and facial nerve manifested after surgery for lung cancer in a 77-year-old female who also had a retroodontoid pseudotumor. Lobectomy was conducted with the patient in a left lateral position. For the purpose of cervical stabilization, the orthopedic surgeon recommended the use of a cervical collar. During the operation, both of her arms were abducted at nearly 80 degrees. On the second postoperative day, the patient complained of sensory disturbances in the lateral area of her left brachium and forearm, which are innervated by the 5th and 6th cervical spinal nerves from the brachial plexus. She also complained that she could not abduct and flex her left shoulder, and could not flex her left elbow at all. Simultaneously, facial nerve palsy was observed in her left lower lip. During the operation, her shoulders were forcibly rotated internally and were extremely abducted, resulting in a narrowed distance between the lower jaw and the shoulder and stretching of the brachial plexus. Under this situation, the cervical collar was pressing strongly upon her neck and lower jaw, which might have produced the brachial plexus complication and facial nerve palsy.     

FK317, a novel substituted dihydrobenzoxazine, exhibits potent antitumor activity against human tumor xenografts in nude mice.

The antitumor effects of FK317, a novel substituted dihydrobenzoxazine, were evaluated using human tumor xenografts (small cell lung cancer, non-small cell lung cancer, stomach cancer, colon cancer, pancreatic cancer, breast cancer, cervical cancer and ovarian cancer). Tumor growth-inhibitory effects and the effective dose-range of FK317 were much stronger and broader, respectively, than those of reference drugs such as mitomycin C, adriamycin, cisplatin, taxol and irinotecan. Furthermore, the body weight decrease and myelosuppression in FK317-treated mice were less than in the animals given any of the reference drugs. To explain this tumor selectivity, the distribution of FK317 was investigated after dosing tumor-bearing mice with the 14C-labelled compound. The concentration of FK317 in tumor tissues was relatively low, and long tumor retention was not observed. However, thin-layer chromatographic separation revealed that the radioactivity in the tumor resided mainly in strongly cytotoxic metabolites, while that in other tissues resided mainly in non-cytotoxic metabolites. These results suggest that FK317 shows strong antitumor activity without side effects, and one reason for this is its specific metabolite pattern. FK317 is now undergoing phase I clinical trials.     

Anti-cachectic effect of FK317, a novel anti-cancer agent, in colon26 and LX-1 models in mice.

The effects of FK317 (11-acetyl-8-carbamoyloxymethyl-4-formyl-6- methoxy-14-oxa-1,11-diazatetracyclo[7.4.1.0(2, 7). 0(10, 2] tetradeca-2,4,6-trien-9-yl acetate), a novel anti-cancer agent, on murine adenocarcinoma colon26- and human lung carcinoma LX-1-induced cachexia were investigated in mice. Mice bearing colon26 or LX-1 s.c. lost weight and became cachectic, associated with tumor growth. FK317 and mitomycin C (MMC) inhibited the growth of both tumors. FK317 ameliorated the weight loss induced by the presence of colon26 or LX-1, while MMC enhanced it. An attenuation of the reduction in the weights of epididymal fat, gastrocnemius muscle and carcass was observed in FK317-treated tumor-bearing mice in both cachexia models, but not in MMC-treated mice. The decreases in the circulating levels of triglyceride, glucose and non-esterified fatty acid, which were induced by the presence of colon26, was partially inhibited by treatment with FK317. Overall, this study revealed that FK317 is a potent anti-cancer drug with anti-cachectic activity, suggesting that FK317 has potential utility for the treatment of cancer.     

Activation of mitochondrial voltage-dependent anion channel by apro-apoptotic BH3-only protein Bim

Bcl-2 family of proteins regulates apoptosis by controlling mitochondrial membrane permeability. We have previously shown that the voltage-dependent anion channel (VDAC) plays a crucial role in apoptotic changes of the mitochondria and its activity is directly regulated by some Bcl-2 family members, including Bcl-2/Bcl-x(L) and Bax/Bak but not Bid. Here, we showed that in isolated mitochondria, Bim induced loss of membrane potential and cytochrome c release like Bax/Bak, with these changes being inhibited by an anti-VDAC antibody. In addition, microinjection of the anti-VDAC antibody significantly reduced Bim-induced apoptosis. Study using purified proteins indicated that Bim directly interacts with the VDAC. Immunoprecipitation analysis revealed that Bim interacts with the VDAC and the interaction is remarkably enhanced during apoptosis. An experiment using liposomes indicated that Bim enhanced VDAC activity, as did Bax/Bak. Furthermore, Bim (but not tBid) was able to induce apoptotic changes of yeast mitochondria in a VDAC-dependent manner, and also induced the lysis of red blood cells, with this effect being inhibited by the anti-VDAC antibody. These results indicate that Bim has an ability to activate directly the VDAC, which plays an important role in apoptosis of mammalian cells.     

Relationships between the in vitro cytotoxicity and transport characteristics of pirarubicin and doxorubicin in M5076 ovarian sarcoma cells, and comparison with those in Ehrlich ascites carcinoma cells

PURPOSE: We sought to determine whether the de novo resistance of M5076 ovarian sarcoma cells, which show sensitivity to pirarubicin (THP), to doxorubicin (DOX) is due to differences in the transport characteristics between THP and DOX, and the results were compared with those for drug-sensitive Ehrlich ascites carcinoma cells. METHODS: The in vitro cytotoxicity of the drugs was assessed by means of the tetrazolium dye assay. Transport experiments were performed by the rapid centrifugation method. RESULTS: In an in vitro cytotoxicity experiment, M5076 cells showed lower sensitivity to DOX than to THP, and the cytotoxicity of THP and DOX toward M5076 cells was lower than toward Ehrlich cells, and these results were similar to those of an in vivo experiment. This was due to the much lower expression of topoisomerase II in M5076 cells than in Ehrlich cells. The amount of intracellular DOX was found to be significantly lower than that of THP in both cell types, and furthermore, little free intracellular DOX was observed in M5076 cells, indicating that the low sensitivity of M5076 cells to DOX was partially a result of the low amount of intracellular DOX. There was no difference in the efflux rate, but there was an apparent difference in the uptake efficiency of the carrier between THP and DOX. CONCLUSIONS: These findings suggest that the cytotoxicities of THP and DOX toward M5076 and Ehrlich cells depend, at least in part, on the uptake efficiency of the carrier.