Prospective evaluation of corrected QT intervals and arrhythmias after exposure to epirubicin, cyclophosphamide, and 5-fluorouracil in women with breast cancer.

BACKGROUND: Corrected QT (QTc) interval prolongation can induce fatal arrhythmias such as torsade de pointes. PATIENTS AND METHODS: To assess the characteristics of QTc intervals and arrhythmias in women with early breast cancer who received FEC100 adjuvant chemotherapy, electrocardiograms (ECGs) were recorded before and after each chemotherapy. Associations between QTc interval prolongation and single nucleotide polymorphisms (SNPs) of potassium channel genes were also investigated. RESULTS: A total of 131 ECG records were obtained in 34 patients who received 153 cycles of FEC100. QTc intervals could be measured in 127 records. There was a significant trend toward QTc interval prolongation after each treatment, persisting through four cycles of chemotherapy (P < 0.001). Median QTc interval prolongations were 13, 11, 18, and 14 ms in the first through fourth cycles of chemotherapy, respectively. QTc intervals differed significantly between cycles 1 and 4 before treatment as well as after treatment (P < 0.05). A single supraventricular premature contraction was noted in 3 (2.3%) of the 131 cycles in 2 (5.9%) of the 34 patients. There was no significant association between QTc interval prolongation and SNPs of potassium channel genes. CONCLUSION: This prospective study confirmed that FEC100 is associated with significant QTc interval prolongation in women with early breast cancer.

Safety and utility of autologous blood transfusion for resection of metastatic liver tumor.

BACKGROUND/AIMS: The purpose of this study was to evaluate the safety and efficacy of predeposit autologous blood transfusion for resection of hepatic metastases. METHODOLOGY: We examined stored blood from 25 patients with advanced colorectal or gastric cancer for carcinoembryonic antigen mRNA using reverse-transcriptase-polymerase chain reaction assay to detect cancer cell in the autologous blood. We also retrospectively evaluated no transfusion (A, n = 44), autologous transfusion (B, n = 15), and homologous transfusion groups (C, n = 26) for perioperative liver function and long-term outcome after undergoing resection of liver metastases. RESULTS: In 5 of 25 patients, carcinoembryonic antigen mRNA was detected immediately after blood donation and after 7 days of storage, but not after 14-21 days of storage. The cumulative 5-year survival rates for groups A, B, and C were not different. However, disease-free survival with colorectal liver metastases was significantly higher in group A than in group C (P = 0.019). Total bilirubin concentrations in group C on the first postoperative day were also significantly higher than group A (P = 0.025). CONCLUSIONS: Stored autologous blood may contain cancer cells, but these decrease or disappear after storage for more than 7 days. For hepatic resection of metastases, transfusion avoidance yields the optimal outcome.

Directional distribution of radiation around an accident at a uranium fuel factory in Tokai-mura, 1999.

A beta-ray survey was carried out on concrete walls of the boundary and buildings after a criticality accident at a factory of JCO Co. Ltd. at Tokai-mura. A remarkable distribution of beta counts was observed on the walls depending on the complex internal and external structures of buildings surrounding a precipitation vessel containing uranium 23 days after the accident. The directional distribution function, based on the beta counts on the walls, was consistent with data concerning the neutron dose rate measured in several directions during the accident, suggesting an anisotropic neutron distribution to the residential area.

Safety and advantage of perioperative autologous blood transfusion in hepatic resection for hepatocellular carcinoma.

BACKGROUND: The safety and advantages of perioperative autologous blood transfusion (ABT) were evaluated on hepatectomy for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Blood samples were obtained and stored from 30 patients with HCC. HCC cells were investigated by the presence of AFPmRNA using RT-PCR after storage. We also reviewed postoperative liver function and the long-term outcomes of 138 patients who underwent hepatectomy receiving ABT compared with patients receiving homologous blood transfusion (HBT) and patients without blood transfusion. RESULTS: AFPmRNA was not detected in all samples stored for more than 14 days. Postoperative ALT, AST and total bilirubin in the HBT group were significantly higher than those of other groups. Patients in the HBT group had significantly lower survival rates than patients in the ABT group. CONCLUSION: ABT was safe after storage and it had advantages compared with HBT with regard to postoperative liver function and survival rate after the hepatectomy for HCC.

Expression of zinc transporter gene, ZnT-1, is induced after transient forebrain ischemia in the gerbil.

To elucidate the molecular mechanisms underlying neuronal death after transient forebrain ischemia, we cloned genes expressed after transient forebrain ischemia in the Mongolian gerbil by a differential display method. A gerbil homolog of rat zinc transporter, ZnT-1, which transports intracellular Zn2+ out of cells, was isolated. Its expression became detectable exclusively in pyramidal neurons of the CA1 region 12 hr after ischemia and reached a maximum from day 1 to day 2 as shown by in situ hybridization. By day 7, expression had disappeared entirely from the cells in the CA1 region, because the neurons had died. No other brain regions exhibited such a significant level of ZnT-1 mRNA expression during this period. Zn2+ was shown to accumulate in CA1 pyramidal neurons expressing ZnT-1 mRNA after the ischemia by using zinquin, a zinc-specific fluorescent dye. When primary hippocampal neurons were exposed to a high dose of Zn2+, ZnT-1 mRNA accumulated. These results suggest that the induction of ZnT-1 mRNA observed in CA1 neurons was caused by an increase in the intracellular Zn2+ concentration. It was reported recently that Zn2+ chelator blocked neuronal death after ischemia and that the influx of Zn2+ might be a key mechanism underlying neuronal death. The induction of ZnT-1 mRNA in CA1 pyramidal neurons fated to die after transient ischemia is of interest to the study of postischemic events and the molecular mechanisms underlying delayed neuronal death.

Effect of systemic zinc administration on delayed neuronal death in the gerbil hippocampus.

The divalent cation zinc has been reported to possess several physiological properties such as blocking apoptotic cell death through an inhibitory effect on Ca(2+)-Mg2+ endonuclease activity, or modulating the neurotoxicity via glutamate receptor subtypes. In the present study, we investigated the effect of peripherally injected zinc on delayed neuronal death seen in the hippocampus after transient global ischemia, in order to elucidate a possible beneficial role on zinc in ischemic neuronal cell death. Forty-five adult Mongolian gerbils of both sexes underwent transient bilateral clipping of the common carotid arteries for 3 min. In the pretreated animals, ZnCl2 (20 mg/kg) was injected subcutaneously once, 1 h before ischemia (superacute group; n = 6) or twice at 24 and 48 h before ischemia (subacute group; n = 14). Histological survey was carried out 3 days later by in situ DNA fragmentation method and 4 days later by hematoxylin-eosin staining by semiquantatively counting dead neurons in the CA1 sector. Subacute zinc pre-administration significantly reduced the nuclear damage and subsequent neuronal death; however, superacutely pre-administered zinc did not protect hippocampal neurons against ischemia but it did not aggravate the effect of ischemia, either. The present study suggested that transfer of exogenous zinc into the intracellular space is required for neuroprotection, presumably via the anti-endonuclease activity.

Effective intervention of low peak bone mass and bone modeling in the spontaneous murine model of senile osteoporosis, SAM-P/6, by Ca supplement and hormone treatment.

SAM-P/6 is a recently developed strain of osteoporotic mice. In this study we tried to determine whether calcium, vitamin D3, parathyroid hormone (PTH), and estrogen modified the peak bone mass of young SAM-P/6 mice, and whether the effect of these medications persisted after treatment had been discontinued. Calcium supplement, PTH, and estrogen treatment increased the peak bone mass of SAM-P/6 mice. To clarify the process by which bone mass was increased in these treated mice, we evaluated their bone formation and resorption by histomorphometry and measured the levels of ions and serum enzymes relevant to bone metabolism. We found that bone formation was increased by calcium supplementation, and bone resorption was decreased by estrogen treatment. Furthermore, the effectiveness of calcium supplement on peak bone mass was retained after treatment had been discontinued, but the effect of estrogen treatment on peak bone mass was reduced after estrogen treatment had been discontinued. The results of this study indicate that calcium supplementation and estrogen and PTH treatment each increased peak bone mass at the midpoint of the femur of SAM-P/6, and that the effect of calcium supplementation, but not that of estrogen treatment, persisted after treatment was discontinued.

'Ischemic tolerance' phenomenon detected in various brain regions.

We investigated the effects of mild and non-lethal ischemic insult on neuronal death following subsequent lethal ischemic stress in various brain regions, using a gerbil model of bilateral cerebral ischemia. Single 10-min ischemia consistently caused neuronal damage in the hippocampal CA1, CA2, CA3 and CA4, layer III/IV of the cerebral cortex, dorsolateral part of the caudoputamen and ventrolateral part of the thalamus. On the other hand, in double ischemia groups, 2-min ischemic insult 2 days before 10-min ischemia exhibited significant protection in the CA1 and CA3 of the hippocampus, the cerebral cortex, the caudoputamen and the thalamus. Five-min ischemic insult 2 days before 10-min ischemia also showed protective effect in the same areas as those of 2-min ischemia except for the CA1 region of the hippocampus, while 1-min ischemic insult exhibited no protective effect in any brain regions. In the immunoblot analysis, both 2- and 5-min ischemia caused increased synthesis of heat shock protein 72 (HSP 72) in the hippocampus, but 1-min ischemia did not. The present study demonstrated that the 'ischemic tolerance' phenomenon was widely found in the brain and also suggested that ischemic treatment severe enough to cause HSP 72 synthesis might be needed for induction of 'ischemic tolerance'.

Hyperthermia-induced neuronal protection against ischemic injury in gerbils.

We investigated the effect of hyperthermic pretreatment before induction of ischemia using a gerbil model of 5-min forebrain ischemia. A single hyperthermic treatment 18 h before ischemia exhibited a partial protective effect, and repetitive hyperthermic pretreatments at 18-h intervals before ischemia showed clear protection against neuronal death in the CA1 area of the hippocampus, whereas single hyperthermic treatment 3, 6, 24, or 50 h before ischemia exhibited little protective effect. This transient and cumulative neuroprotective effect of hyperthermic pretreatment strongly suggested the involvement of stress reactions after hyperthermia in the protective mechanism against ischemic neuronal death.

Influence of lesions of the limbic-hypothalamic system on metabolic response of pyruvate to daily repeated immobilization stress in rabbits.

The pyruvate metabolic response to the 1st exposure (exposure on the 1st day) to immobilization stress (IMO) were considerably altered by lesions of the periventricular arcuate nucleus (ARC), ventromedial hypothalamus (VMH), stria terminalis (ST) and dorsal fornix (FX). The pyruvate metabolic responses to IMO were completely abolished by seven times repetition of exposure to IMO in the rabbits with lesions of ARC and VMH; they were similar to sham-operated groups. In rabbits with lesions of ST and FX, the pyruvate metabolic responses to the 7th exposure (exposure on the 7th day) to IMO were almost the same as those after the 1st exposure to IMO, but these metabolic responses were completely abolished by the seven times repetition of exposure to IMO in the sham-operated animals. These results suggest that firstly the ARC, VMH, amygdala (AMYG)-ST system and dorsal hippocampus (HPC)-FX system are involved in the pyruvate metabolic responses to the 1st exposure to IMO, and secondly, that the AMYG-ST system and the HPC-FX system are involved in the disappearance process of pyruvate metabolic responses to IMO by the daily repetition of exposure to IMO.

Further observation on the lack of active uptake system for substance P in the central nervous system.

Crude mitochondrial P2 fractions from bovine hypothalamus and substantia nigra, slices from rabbit spinal cord and mesencephalon and glial fractions from rabbit brain were incubated with [3H]-substance P and the uptake was measured and compared with those for 5-HT and GABA. Substance P was to some extent taken up into the fractions but this uptake was neither temperature nor time dependent and the pellet/medium ratios were less than 1. Similar results were obtained in high potassium treated slices from rabbit mesencephalon. The rate of uptake for [3H]-substance P increased linearly in proportion to the medium concentration, suggesting a non-saturable binding. These results, together with our previous observations provide strong evidence that nerve terminals and glial cells lack a temperature sensitive, active uptake system capable of terminating transmitter action of substance P at the synapse.