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991.
Histopathological study of the effects of a single intratracheal instillation of surface active agents on lung in rats 总被引:3,自引:0,他引:3
Suzuki M Machida M Adachi K Otabe K Sugimoto T Hayashi M Awazu S 《The Journal of toxicological sciences》2000,25(1):49-55
Pulmonary drug administration of most peptide/protein drugs is characterized by low bioavailability due to low permeability. Surface active agents have been tested as an absorption enhancer, but few studies have been carried out on the local toxicity of these additives. In the present study, to clarify the toxic effects of surface active agents on the lung, a relatively high concentration (1%) of polyoxyethylene 9 lauryl ether (Laureth-9) and sodium glycocholate (SGC) was given to rats in a single intratracheal instillation (100 microliters/rat), and the lung was evaluated histopathologically. In the rats treated with Laureth-9, lung lesions were observed in the bronchi to alveoli. At 1 day after administration, edema, hemorrhage and inflammatory cell infiltration due to degeneration and desquamation of epithelium were observed. At 3 and 7 days after administration, the wound healing process resulting from the lung injury, such as hyperplasia of epithelium and sporadic fibrosis, was noted. SGC also induced lung lesions with a similar histopathological nature, whereas the lesions were mostly confined to the alveoli. These results suggest that surface active agents induce acute inflammation of the lung by intratracheal instillation, that the distribution of lesions is different among surface active agents, and moreover that pathological examination is indispensable for clarifying local toxicity of absorption enhancers in pulmonary drug-delivery studies. 相似文献
992.
993.
Liquid chromatographic determination of urinary 6beta-hydroxycortisol to assess cytochrome p-450 3A activity in HIV positive pregnant women 总被引:3,自引:0,他引:3
Homma M Beckerman K Hayashi S Jayewardene AL Oka K Gambertoglio JG Aweeka FT 《Journal of pharmaceutical and biomedical analysis》2000,23(4):629-635
Assessing the activity of CYP3A4 is important for predicting the pharmacokinetic behavior of protease inhibitors in HIV positive patients, especially in pregnant women. The endogenous hormonal ratio of 6beta-hydroxycortisol (beta-OHF) to cortisol (F) in the urine is an index for metabolic enzyme activity of cytochrome p-450 (CYP) 3A4. Because the ratio is a unique way to assess the enzyme activity without using any exogenous probes for this isozyme, it is practical for use in pregnant women. In this paper, we describe a method using high performance liquid chromatography (HPLC) for 6beta-OHF in urine from pregnant women to estimate the ratio of 6beta-OHF/F. Urinary 6beta-OHF was measured by using C18-cartridge solid phase extraction and isocratic HPLC. Aliquots (1 ml) of urine samples spiked with internal standard, 6beta-hydroxyprednisolone (6beta-OHPSL), were alkalinized with NaOH, then applied to C18-cartridges, which were washed with water and hexane and eluted with ethyl acetate. After the effluents were dried and reconstituted in 10% acetonitrile, the samples were analyzed by HPLC using an isocratic mobile phase (acetic acid/acetonitrile/50 mM potassium dihydrogenphosphate: 0.2/9/90.8; v/v) and ultraviolet detection at 245 nm. The recoveries of 6beta-OHF from C18 cartridges were 93.2 and 93.9% when the authentic 6beta-OHF was added to the urine sample at the concentration of 50 and 300 ng/ml, respectively. Intra- and inter-day variations estimated at concentrations of 113-674 ng/ml were 2.9-5.6 and 4.9-8.1%, respectively. The method was applied to morning urine samples collected from HIV-positive pregnant women managed with protease inhibitor containing anti-retroviral regimens. 相似文献
994.
S Kurozumi T Hayashi S Takebayashi N Okanishi 《Nihon Jibiinkoka Gakkai kaiho》1968,71(2):Suppl 4:16-Suppl 4:34
995.
996.
Yoshida T Eguchi H Nakachi K Tanimoto K Higashi Y Suemasu K Iino Y Morishita Y Hayashi S 《Carcinogenesis》2000,21(12):2193-2201
We have previously shown that the distal promoter (promoterB) of the estrogen receptor 相似文献
997.
Yaginuma Y Yamashita T Ishiya T Morizaki A Katoh Y Takahashi T Hayashi H Ishikawa M 《Molecular carcinogenesis》2000,27(2):110-116
The PTEN/MMAC1 gene, located on human chromosome 10q23, has recently been implicated as a candidate tumor suppressor gene in human cancers. In the present study, 12 uterine cancer cell lines and 87 uterine cancers of various grades and histological type were analyzed for PTEN/MMAC1 gene. Three of 44 endometrial carcinoma (7%) showed no PTEN/MMAC1 mRNA expression by RT-PCR analysis. Sequencing analysis of entire coding region of PTEN/MMAC1 gene revealed mutations in three of six endometrial cancer cell lines (50%) and 17 of 44 endometrial cancer tissues (39%). In contrast, for cervical cancers, only one of six cancer cell lines (2%) showed mutation, and one of 43 cancer tissues (2%) had an abnormality. Overall, 36% of the abnormal spots were located in exon 5, 24% were in exon 8, 16% were in exon 3, and 8% were in exon 6, and single cases of abnormality were found in exons 1, 4, and 7. Our results revealed that, in total, 60% of abnormalities were clustered in exons 5 and 8. Exon 5 is a functional domain of the PEN/MMAC1 gene, and therefore, abnormalities in this region may be important for loss of PTEN/MMAC1 gene function. Finally, we found a high frequency of PTEN/MMAC1 gene abnormalities in endometrial carcinomas but a low frequency in cervical carcinomas. These findings suggest that disruption of PTEN/MMAC1 by mutation or absence of expression may contribute to the pathogenesis or neoplastic evolution in a large proportion of endometrial carcinomas but in a small proportion of cervical carcinomas. 相似文献
998.
A case of stage IVb (H2P0N4T4) gastric cancer successfully treated with neoadjuvant chemotherapy (PMFE therapy) 总被引:1,自引:0,他引:1
Fushida S Minatoya T Hayashi T Ajisaka H Bando E Taniguchi K Fujimura T Nishimura G Yonemura Y Miwa K 《Gan to kagaku ryoho. Cancer & chemotherapy》2000,27(2):271-275
A 69-year-old man was examined at our hospital because of a sense of upper abdominal fullness. He was diagnosed as having stage IVb (H2P0N4T4) gastric cancer and treated with neoadjuvant chemotherapy. One course of the regimen consisted of 10 mg CDDP (day 1-5), 10 mg MMC (day 1), 250 mg 5-FU (day 1-20) and 50 mg ETP (day 6, 7). The patient underwent the regimen three times in succession. After the chemotherapy, his hepatic metastases showed necrotic changes and the swelling of the para-aortic lymph nodes disappeared on a CT scan. A histological examination revealed that the cancer cells had completely vanished both at the site of the hepatic tumor and the para-aortic lymph nodes. This combination chemotherapy, named PMFE therapy, is considered effective without serious side effects for gastric cancer in patients with non-curative factors. 相似文献
999.
Induction of apoptosis by gallic acid in human stomach cancer KATO III and colon adenocarcinoma COLO 205 cell lines 总被引:2,自引:0,他引:2
Antitumor effects of gallic acid on human stomach cancer KATO III cells and human colon adenocarcinoma COLO 205 cells were investigated. The exposures of KATO III and COLO 205 cells to gallic acid led to both growth inhibition and induction of apoptosis. Morphological changes showing apoptotic bodies were observed in both the cell lines treated with gallic acid. The fragmentations by gallic acid of DNA to oligonucleosomal-sized fragments, that are characteristics of apoptosis, were observed to be concentration- and time-dependent. These findings suggest that growth inhibitions by gallic acid of KATO III cells and COLO 205 cells result from the apoptosis induced by gallic acid. Thus, gallic acid might be a candidate drug for digestive gut cancer treatment to overcome the resistance to chemotherapeutic drugs. 相似文献
1000.
K Morinaga S Hayashi Y Matsumoto N Omiya J Mikami M Ueda H Sato Y Inoue S Okawara 《No shinkei geka. Neurological surgery》1992,20(1):45-49
For intracranial diseases, plasma atrial natriuretic peptide (ANP), antidiuretic hormone (ADH) and aldosterone were determined and their effects on the development of hyponatremia with central origin were studied. The subjects were 71 cases of intracranial diseases which were admitted to our hospital during a period of 1 year from March, 1989 to March, 1990. The diseases were broken down to subarachnoid hemorrhage 26 cases, hypertensive intracerebral hemorrhage 19 cases, head injury 12 cases, cerebral infarction 11 cases and 3 other cases. Serum-urine electrolytes, plasma ANP and ADH were determined in the acute stage on Day 1 to 4, in the hyponatremia stage on Day 5 to 14 and in the chronic stage on Day 15 downward. Hyponatremia was defined as the serum sodium level of 130 mEq/l or less. Cases evidently having other causes such as heart failure and renal insufficiency were excluded. In the normal control group of persons who were admitted to our hospital for a close checkup (n = 20), plasma ANP was 26.5 +/- 11.6 pg/ml (10-50); levels of 50 pg/ml or more were regarded as abnormally high. 1) Hyponatremia was found in 18 cases (25.4%), subarachnoid hemorrhage in 7 cases, hypertensive intracerebral hemorrhage in 4 cases, head injury in 5 cases and others in 2 cases. 2) The time of onset of hyponatremia was on the 8.3 hospital day. The duration was 7.2 days. The minimum serum sodium level was 124.6 mEq/l. 3) There was no significant change in the plasma aldosterone level at each stage.2+ Predicting development of hyponatremia from plasma ADH and ANP levels in the acute stage is difficult. Inadequate secretion of ANP rather than ADH appeared to be an important factor for the development of hyponatremia, but the plasma ANP level was not always abnormally high, so involvement of other sodium diuretic factors should also be kept in mind. 相似文献