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991.
Ishigaki T Sugano W Ike M Kawagoshi Y Fukunaga I Fujita M 《Journal of basic microbiology》2000,40(3):177-186
In order to assess the degradability of plastics in solid waste disposal landfill sites, microbial populations capable of degrading five kinds of plastic-constituting polymers, poly epsilon-caprolactone (PCL), polylactic acid (PLA), polyethylene glycol (PEG), poly-beta-hydroxybutyrate (PHB) and cellulose acetate (CA), in a sea-based solid waste disposal site were investigated. Enumeration of aerobic and anaerobic polymers-degrading microorganisms (PDMs) was performed against to total 8 leachate samples, which were seasonally collected from the facultative pretreatment pond and the aerated lagoon. Both aerobic and anaerobic PDMs for natural polymers, PHB and CA, were found in all of the samples, while those for chemically-synthesized polymers, PCL, PLA and PEG, could not be always detected. In most cases, the ratios of the PHB- and CA-degraders to the heterotrophic bacterial population were more than 0.1%. On the other hand, the ratios of PCL-, PLA- and PEG-degraders were often much lower. These data indicate that the plastics degradation potential is commonly present in the studied disposal site, and that the degradation potential for plastics composed of chemically-synthesized polymers is inferior to that of natural polymers. Population sizes of the PDMs correlated to those of heterotrophic bacteria, and the counts of aerobic heterotrophic bacteria and PDMs in the aerated lagoon tended to be higher than those of anaerobic ones, indicating that the aeration of the leachate resulted in the activation of growth of whole aerobic microbial community including the PDMs. 相似文献
992.
Takeuchi K Murata K Funaki K Fujita I Hayakawa Y Morita H 《Journal of perinatal medicine》2000,28(3):228-231
We report a case of successful pregnancy in a woman who was initially diagnosed with renal failure in mid-pregnancy. She was started on hemodialysis, and her fluid balance was serially monitored with bioelectrical impedance analysis. Her body weight decreased and bioelectrical impedance values increased, along with resolution of pulmonary edema in the process of the removal of excessive fluid retention with hemodialysis. The bioelectrical impedance values decreased immediately after the usual dose of oral ritodrine was administered, partly because producing sodium and water retention by ritodrine were enhanced in the setting of fluid imbalances. This decrease preceded the onset of pulmonary edema, while no changes were noted in maternal body weight before hemodialysis. These results suggest that the serial measurement of bioelectrical impedance values enables more reliable and earlier detection of abnormal water retention in pregnant women undergoing dialysis than the effect of body weight changes. 相似文献
993.
The pharyngeal villiform processes of the hibernating soft-shelled turtle, Trionyx sinensis japonicus, were studied by immunohistochemistry for Na+/K+-ATPase in combination with a mitochondrion staining. Mitochondria-rich cells were recognized in the epithelium constituting the distal part of most processes, and exclusively showed the Na+/K+-ATPase immunoreactivity. These cells tended to attract each other to form clusters. When considering the physiological and histological data previously obtained in corresponding cells in the fish gill epithelium, the mitochondria-rich cells in the hibernating turtle were suggested to be involved in the electrolyte (Na+) uptake from the aquatic habitat. 相似文献
994.
Nakagawa M Mizuno M Kawada M Uesu T Nasu J Takeuchi K Okada H Endo Y Fujita T Tsuji T 《Journal of gastroenterology and hepatology》2001,16(2):184-189
BACKGROUND: We have previously shown that expression of decay-accelerating factor (DAF), a complement regulatory protein, is enhanced immunohistochemically on the luminal surface of cancer glands in human colorectal cancer and is detected in stool specimens of patients with colorectal cancer. The amount of DAF present in the stools might be influenced by the stability of DAF on the cell surface which is regulated by biochemical properties such as glycosylation of the protein. In the present study, to help elucidate the mechanism for the release of DAF from human colorectal cancers, we biochemically analyzed DAF expression by western and northern blotting by using surgically resected specimens of colorectal cancers. METHODS: Surgically resected colorectal cancer tissues were obtained from 10 patients. Expression of DAF was determined by western and northern blotting, and glycosylation of DAF protein was analyzed with glycosidase digestion. RESULTS: Northern blot analysis demonstrated that the expression of DAF mRNA in colorectal cancer was enhanced two- to threefold compared with normal tissues. In western blotting, expression of DAF protein in the cancer tissue was increased, and heterogeneity in the apparent molecular weight of DAF was observed among patients. When o-linked sugars were removed, this heterogeneity of DAF size diminished. CONCLUSIONS: The polymorphic expression of DAF in colorectal cancer is likely to reflect variability in the o-glycosylation of the protein. We speculate that this variability could affect the stability of DAF on the surfaces of cancer cells and, in turn, the amount of DAF shed into the stools of colorectal cancer patients. 相似文献
995.
996.
Bandoh S Fujita J Fukunaga Y Ohtsuka S Susaki K Yang Y Kobayashi S Takahara J 《Japanese journal of clinical oncology》2001,31(2):82-85
Two men with occupational exposure to asbestos were admitted to our hospital with minute pleural changes on their chest CT image. Conventional computed tomography (CT) scans of the chest showed slightly thickened interlobar fissures and a small amount of pleural effusion. In addition, high-resolution CT showed small nodular opacities on interlobar fissures. There were no intrapulmonary mass shadows, pleural plaques or other extrapulmonary mass shadows. These roentgenographical findings were very similar to each other. Hyarulonic acid values obtained from their pleural fluid were extremely high. Finally, we diagnosed them as having malignant mesothelioma using an immunocytochemical technique and electronmicroscopy. We conclude that HRCT is helpful in the diagnosis of malignant mesothelioma, particularly in its early manifestation such as nodular opacities of interlobar fissures. 相似文献
997.
998.
The relationship between prognosis and CEA-dt after hepatic resection in patients with colorectal carcinomas. 总被引:4,自引:0,他引:4
AIMS: CEA-doubling time (CEA-dt) was calculated by measuring serum CEA at two voluntary points. As CEA-dt is correlated with tumour doubling time the growth rate of liver metastasis could be determined. We investigated the relationship between CEA-dt and prognosis to determine the indications for resection of liver metastasis. METHODS: We examined 334 patients diagnosed with resected liver metastasis of colorectal carcinoma. Patients were divided into three categories based on CEA-dt; Group A, CEA-dt <30 days; Group B, 30 days =cCEA-dt <80 days; and Group C, CEA-dt >/=s80 days. Clinicopathological parameters, the 3-year or 5-year survival rate and the rate of recurrence were compared among the three groups. RESULTS: In Group A, the survival time after hepatic resection was significantly shorter compared to the other groups. Furthermore, multiple liver metastasis showed slightly reduced CEA-dt levels compared with solitary metastasis, but even in patients with solitary liver metastasis, the rate of survival was poor. In 70% of Group A patients, recurrent tumour was recognized within 1 year of hepatic resection. CONCLUSION: When surgery for liver metastasis of colorectal cancer is considered. Group A patients should be recognized as having a poor prognosis and a high rate of recurrence after hepatic resection, and CEA-dt should be employed as a prognostic factor. 相似文献
999.
Yamamoto H Hirose K Hayasaki Y Masuda M Kazusaka A Fujita S 《Archives of toxicology》1999,73(8-9):457-464
The Long-Evans Cinnamon (LEC) rat is a mutant strain of rats that accumulate copper (Cu) in the liver in much the same way
as individuals who suffer from Wilson's disease (WD) and has been suggested as a model for this disease. Lipid peroxidation
(LPO) is considered to be involved in the toxic action of Cu in the livers of LEC rats. We investigated the mechanism of LPO
in the livers of LEC rats showing apparent signs of hepatitis. Several-fold higher LPO levels were observed in post-mitochondrial
supernatant (S-9) fraction of livers from hepatitic LEC rats than in those from Wistar rats. To mimic living cells, we introduced
NADPH-generating system (NADPH-gs) into the S-9 incubation system. Thus was ensured a constant supply of NADPH to vital enzymes
that may be directly or indirectly involved in the generation and/or elimination of reactive oxygen species (ROSs), such as
glutathione reductase (GSSG-R), which require NADPH for their reactions. The levels of LPO in liver S-9 from hepatitic LEC
rats were further increased by incubating liver S-9 at 37 °C in the presence of NADPH-gs. This increase was inhibited by EDTA,
butylated hydroxytoluene (BHT), and catalase (CAT), suggesting that some metal, most likely the accumulated Cu, and ROSs derived
from hydrogen peroxide (H2O2) are involved in the increased levels of LPO in the livers of hepatitic LEC rats. The requirement of NADPH-gs for enhanced
LPO in the livers of hepatitic LEC rats indicates the consumption of NADPH during reactions leading to LPO. It is known that
H2O2, and consequently hydroxyl radical are generated during Cu–catalyzed glutathione (GSH) oxidation. The cyclic regeneration
of GSH from GSSG by NADPH-dependent GSSG-R in the presence of NADPH-gs may cause sustained generation of hydroxyl radical
in the presence of excess free Cu. The generation of H2O2 in S-9 fraction of livers from hepatitic LEC rats was observed to be significantly higher than that in S-9 fraction of livers
from non-hepatitic LEC rats and Wistar rats. Moreover, in addition to the reported decrease in glutathione peroxidase (GPX)
activity, we found that CAT activity was markedly decreased in LEC rats with hepatitis. The increased generation of H2O2 with reduced activities of GPX and CAT may result in cellular accumulation of H2O2 in the liver of hepatitic LEC rats. Taken altogether, it is suggested that the accumulated H2O2 undergoes the Fenton-type reaction with also accumulated free Cu, thus generating hydroxyl radical in the livers of hepatitic
LEC rats and increasing LPO levels in these animals.
Received: 20 April 1999 / Accepted: 2 September 1999 相似文献
1000.
We previously reported that lipopolysaccharide (LPS) injected intracerebroventricularly (i.c.v.) at an ineffective dose (0.1 μg/rat)
decreased the drug metabolizing activities and related cytochrome P450 (CYP) isozymes in rat liver microsomes when injected
intraperitoneally (i.p.). The dose study (doses <0.1 μg intracerebrally and >0.1 μg i.p.), which was carried out to examine
how much more effective is i.c.v.-LPS than i.p.-LPS, showed that the pattern of alteration of expression of CYP isozymes induced
by i.c.v.-LPS was different from that caused by i.p.-LPS at an effective dose (10 μg/rat). These results indicate that the
decrease in hepatic CYP isozymes caused by i.c.v.-LPS could not be explained by the LPS leaked from the brain, suggesting
that the decrease in hepatic CYP isozymes by i.c.v.-LPS may be caused by a central action of LPS. In this study, the possible
involvement of sympathetic nervous and adrenocortical systems in the down-regulation of CYP isozymes by i.c.v.-LPS was investigated
using surgical or chemical sympathetecomized or adrenalectomized rats. The norepinephrine (NE) content in the liver in rats
with surgical hepatic sympathetectomy was reduced by 88% compared with that of sham-operated rats that received i.c.v.-saline
and 85% compared with that of sham-operated rats that received i.c.v.-LPS, indicating that hepatic denervation was successful.
The NE content in the liver in rats chemically sympathetectomized by two i.p. injections of 6-hydroxydopamine (40 mg/kg each
time) 1 and 2 days before i.c.v. injection was reduced by 82% in i.c.v.-saline-treated and by 74% in i.c.v.-LPS-treated groups
compared with that in rats pretreated with i.p.-saline. These results indicate that sympathetic NE terminals were effectively
removed. Intracerebroventricular LPS decreased the total P450 content and the activities of CYP dependent drug metabolizing
enzymes, ethoxyresorufin O-deethylase (EROD), pentoxyresorufin O-depentylase (PROD), imipramine N-demethylase (IMND) and erythromycin
N-demethylase (ERND) after 24 h in both sympathetectomized rats and non-denervated rats. Adrenalectomy (ADX) reduced the level
of corticosterone in serum by 81% compared to sham-operated rats, indicating that adrenalectomy was successful. ADX did not
inhibit the decrease in the total P450 content and the metabolism of drugs induced by i.c.v.-LPS, but more profoundly emphasized
the inhibitory effect of i.c.v.-LPS than the sham-operation. These results suggest that the sympathetic nervous systems both
directly and indirectly innervating the liver do not participate in the primary mechanism of the decrease in the activities
of CYP isozymes in rat liver microsomes induced by i.c.v.-LPS. Also, the adrenal glands, especially the adrenocortical system,
play a suppressive role in the decrease in CYP isozymes caused by i.c.v.-LPS.
Received: 31 August 1998 / Accepted: 24 November 1998 相似文献