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31.
Uchimura Y Sata M Suzuki H Akiyoshi F Tanaka K Ono N Kage M Kojiro M Tanikawa K 《International journal of oncology》1997,11(5):1103-1107
Schistosomiasis japonica (SCJ) patients frequently develop hepatocellular carcinoma (HCC). This study investigated relationship between SCJ infection, hepatitis virus infection, and incidence of HCC, in 25 patients with chronic SCJ infection and HCC (SCJ with HCC group), 51 patients with chronic SCJ infection without HCC (SCJ group) and 65 HCC patients without SCJ (HCC group). Number of patients who were positive to HBsAg or hepatitis B virus DNA were 4 (16.0%) in the SCJ with HCC group, none (0%) in the SCJ group, and 5 (7.9%) in the HCC group; while number of patients who were positive to anti-hepatitis C virus antibody were 21 (87.5%) in the SCJ with HCC group, 3 (5.9%) in the SCJ group, and 58 (84.6%) in the HCC group. Biopsy was performed for all patients, and background histological features of each specimen were evaluated based on the histological activity index scoring system. Mean scores of inflammatory changes in both the portal area and parenchyma in the SCJ with HCC group were significantly higher than those in the SCJ group. Nodular formation which is common in post-viral hepatitis was frequently observed in the SCJ with HCC group, and histological changes in non-cancerous area of the SCJ with HCC group showed the characteristics of chronic viral hepatitis. We conclude that infection of hepatitis virus, particularly hepatitis C virus, affects synergistically on the hepatocarcinogenesis in patients having SCJ infection. 相似文献
32.
Li J Mori M Yang Y Inoue H Mimori K Shibuta K Nakashima H Mafune K Shimada Y Barnard G Sugimachi K Akiyoshi T 《International journal of oncology》1995,7(2):257-260
The multiple tumor suppressor 1 (MTS1) gene is homozygously deleted frequently in cell lines derived from a wide variety of tumors. We investigated the deletion of the MTS1 gene in esophageal cancer cell lines and primary esophageal squamous carcinomas using the polymerase chain reaction. Sixteen and 15 of 23 esophageal cancer cell lines showed homozygous deletion of MTS1 exon 1 and exon 2, respectively, while none of 21 primary esophageal carcinomas showed the deletion. An analysis of MTS1 gene mutations was carried out by direct DNA sequencing in 8 cell lines and 21 primary carcinomas showing no homozygous deletion. In contrast to previous reports of esophageal carcinoma, there were no mutations recognized in the region sequenced. Our study suggests that the inactivation of the MTS 1 gene may play an important role in esophageal carcinoma cell lines but may be less important in primary carcinomas of the human esophagus. 相似文献
33.
A novel mutation of CHRNA4 responsible for autosomal dominant nocturnal frontal lobe epilepsy 总被引:23,自引:0,他引:23
Hirose S Iwata H Akiyoshi H Kobayashi K Ito M Wada K Kaneko S Mitsudome A 《Neurology》1999,53(8):1749-1753
OBJECTIVE: To identify the mutation responsible for autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) in a nonwhite family. BACKGROUND: ADNFLE is newly recognized as an entity of idiopathic partial epilepsy. Recently, two different mutations of the neuronal nicotinic acetylcholine receptor alpha4 subunit (CHRNA4) gene were identified in a white family as a cause of ADNFLE. METHODS: Four affected and three unaffected individuals in three generations of a Japanese family with ADNFLE, and 100 unrelated healthy Japanese volunteers were studied. Clinical features and EEG findings in affected individuals were consistent with those of ADNFLE reported in white families with ADNFLE. Mutations within the CHRNA4 gene were screened for using single-strand conformation polymorphism analysis (SSCA) and were determined by direct sequencing. The mutation identified was sought in volunteers by the amplification refractory mutation system. RESULTS: A C-to-T exchange (C755T) was found in exon 5 of the CHRNA4 gene on one allele of affected individuals. C755T segregated in affected individuals and was not found in 200 alleles obtained from the volunteers. C755T replaced serine 252 (Ser252) in the second membrane-spanning domain (M2) of CHRNA4 with a leucine. Ser252 is conserved characteristically in the alpha-subunit of acetylcholine receptor and is considered to play an important role in channel function. CONCLUSION: C755T is a novel missense mutation of the CHRNA4 gene causing autosomal dominant nocturnal frontal lobe epilepsy in this Japanese family. 相似文献
34.
In order to examine the involvement of CCK in the formation of anxiety, we have investigated whether CCKB receptor antagonist PD135158 suppressed conditioned fear stress. Rats were individually subjected to 30 min of inescapable electric footshock in a chamber with a grid floor. First, the rats were individually subjected to 30 min of footshock. Twenty-four h after the footshock, the rats were again placed in the chamber and observed for 5 min without shocks. PD135158 was administered 30 min before placing the rats in the chamber again. Secondly, PD135158 was administered 30 min before footshock. Thirdly, PD135158 was administered 5 min after footshock. Administration of PD135158 30 min before conditioned fear stress significantly reduced freezing behavior. Administration of PD135158 30 min before footshock also significantly reduced freezing behavior. But, administration of PD135158 5 min after footshock did not significantly reduce freezing behavior. PD135158 blocked not only the acquisition but also the expression of conditioned fear. These results suggest that the CCKB receptor might play an important role in conditioned fear stress and that it might be related to anxiety. 相似文献
35.
S Kasuga M Ushijima N Morihara Y Itakura Y Nakata 《Nihon yakurigaku zasshi. Folia pharmacologica Japonica》1999,114(3):191-197
The effect of aged garlic extract (AGE) on stress induced hyperglycemia was investigated using the immobilization stress model in mice. After the exposure to immobilization stress for 16 hr per day for 2 consecutive days, the adrenal glands of the mice hypertrophied, and their serum glucose level and corticosterone secretion became elevated, but insulin secretion did not change. These results suggest that the elevation of serum glucose was probably due to the stimulation of the pituitary-adrenocortical axis by the stress. Pretreatment of AGE (5 and 10 ml/kg, p.o.) significantly prevented adrenal hypertrophy, hyperglycemia and elevation of corticosterone, but did not alter serum insulin level. The efficacy of AGE was the same as that of diazepam (5 mg/kg, p.o.). From these results, it is suggested that AGE may prevent stress-induced hyperglycemia, which is the risk of suffering from diabetes mellitus and its progression. 相似文献
36.
The ability of lidocaine to suppress activity of single vagal afferent fiber and that of phrenic nerve was studied in 20 cats anesthetized with pentobarbital. Slowly adapting stretch receptors (SAR, n = 16) and rapidly adapting stretch receptors (RAR, n = 7) were identified by their discharge pattern to pulmonary inflation. Intravenous lidocaine (1mg·kg–1 or 2mg·kg–1) produced a suppression of SAR activity but not of RAR activity. Suppression of phrenic nerve activity lasted much longer than that of SAR. These findings indicate that iv lidocaine acts more dominantly on CNS than on peripherals. We conclude that iv lidocaine prevents cough and hemodynamic changes caused by airway manipulation mainly through its action on CNS and not on peripherals (peripheral nerves or their receptor).(Aoki M, Harada Y, Namiki A, et al.: Effects of intravenously administered lidocaine of pulmonary vagal afferents and phrenic nerve activity in cats. J Anesth 6: 395–400, 1992) 相似文献
37.
This study was designed to investigate differences in epidural analgesic spread between catheter and needle injections in 48 patients with comparable physical characteristics. The spread of analgesia in the catheter injection group with a 0.24ml·sec–1 injection rate (n = 16) was 16.8 ± 1.5 spinal segments and that in the needle injection group at the same injection rate (n = 16) was 12.5 ± 1.8 spinal segments (P 0.01). Needle injection at the faster rate of 1.2ml*237sec–1 (n = 16) produced a significantly greater spread of analgesia than with the 0.24ml·sec–1 rate through the needle (16.2 ± 1.6 vs 12.5 ± 1.8 spinal segments, P 0.01). Thirteen of 16 patients receiving the fast needle injection complained of back compression or discomfort during the injection.The injection through an epidural catheter and the fast (1.2ml·sec–1) injection through a needle produced extensive and equivalent epidural analgesic spread. However, because of patients discomfort with fast injection through the needle, the authors conclude that when using continuous epidural anesthesia, the initial injection of local anesthetic should be administered through the epidural catheter not the needle.(Omote K, Namiki A, Iwasaki H: Epidural administration and analgesic spread: comparison of injection with catheters and needles. J Anesth 6: 289–293, 1992) 相似文献
38.
Fumio Furukawa Akiyoshi Nishikawa Takayoshi Imazawa Ken-ichiro Kasahara Michihito Takahashi 《Cancer science》1998,89(2):131-136
The modifying effects of quinacrine administration during the post-initiation phase of carcinogenesis were investigated in hamsters treated with N -nitrosobis(2-oxopropyl)amine (BOP). Female Syrian hamsters were given three weekly s.c. injections of BOP at a dose of 10 mg/kg and then 300 or 100 ppm quinacrine in their diet for 37 weeks. Additional groups of animals received the BOP injection alone, or only the 300 ppm quinacrine treatment as BOP-negative controls. At week 40 of the experiment, all surviving animals were killed and development of proliferative lesions was assessed histopathologically. The multiplicity of pancreatic adenocarcinomas and dysplastic lesions per hamster was significantly higher ( P <0.01 and P <0.05) in the BOP/Q100 group (1.92 and 1.78) than in the BOP-alone group (1.07 and 0.79). The incidence of hepatocellular adenomas plus carcinomas was also significantly elevated ( P <0.05) in the BOP/Q300 and BOP/Q100 groups. In contrast, the multiplicity of lung adenomas plus adenocarcinomas was significantly decreased ( P <0.05) by the Q300 treatment. Neither the incidence nor the multiplicity of renal cell tumors (adenomas and carcinomas) or nephroblastomas significantly differed between the BOP-treated groups. Electron microscopic examination revealed an abundance of myeloid lamellar bodies filling the cytoplasm of hepatocytes and pancreatic ductular and acinar cells, and epithelial cells of the gallbladder in the quinacrine-treated animals, the degree being dose-dependent. Our results indicate that quinacrine enhances pancreatic and hepatic carcinogenesis in hamsters induced by BOP. 相似文献
39.
Akiyoshi Nishikawa Takako Ikeda Hwa-Young Son Kazushi Okazaki Takayoshi Imazawa Takashi Umemura Shuichi Kimura Masao Hirose 《Toxicological sciences》2005,86(2):258-263
We have reported that excess soybean treatment and iodine deficiency synergistically interact, resulting in remarkable induction of thyroid hyperplasias in rats. In the present study, modifying effects of excess soybean and iodine-deficient diets were investigated in the post-initiation phase of N-bis(2-hydroxypropyl)nitrosamine [DHPN]-initiated thyroid tumorigenesis in rats. AIN-93G in which casein was replaced with gluten was used as a basal diet to avoid possible iodine contamination. In Experiment 1, F-344 rats of both sexes were sc injected with DHPN at a dose of 2800 mg/kg body weight and then fed a diet containing 0%, 0.8%, 4%, or 20% defatted soybean for 12 weeks, with proportional replacement of gluten by soybean flour. Although no thyroid proliferative lesions were found in any group, the absolute thyroid weights were significantly (p < 0.01) elevated with the 20% soybean treatment. In Experiment 2, after similar sc injection of DHPN, rats were fed a basal diet or a diet containing 20% soybean under iodine normal or deficient conditions for 12 weeks. Soybean feeding to both sexes under iodine deficient but not normal conditions dramatically enhanced the development of thyroid follicular adenomas (p < 0.01) and adenocarcinomas (p < 0.05), in good agreement with decrease in thyroxine and increase in thyroid-stimulating hormone. Thus co-exposure to excess soybean and iodine deficiency results in synergistic promotion of DHPN-initiated thyroid tumorigenesis in rats, of which mechanisms appear to primarily involve effects on serum hormone levels. 相似文献
40.