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51.
The in vitro metabolism of fenthion and its sulfoxide (fenthion sulfoxide) in sea bream (Pagrus major) and goldfish (Carassius auratus) was investigated and compared with that in rats. Fenthion was oxidized to fenthion sulfoxide and the oxon derivative, but not to its sulfone, in the presence of NADPH by liver microsomes of sea bream, goldfish, and rats. These liver microsomal activities of the fish were lower than those of rats but were of the same order of magnitude. The NADPH-linked oxon- and sulfoxide-forming activities of liver microsomes of the fish and rats were inhibited by SKF 525-A, metyrapone, alpha-naphthoflavone, and carbon monoxide. The oxidizing activity to fenthion sulfoxide was also inhibited by alpha-naphthylthiourea. Several cytochrome P450 isoforms and flavin-containing monooxygenase 1 exhibited these oxidase activities. Fenthion sulfoxide was reduced to fenthion with liver cytosol of the fish and rats upon addition of 2-hydroxypyrimidine, N(1)-methylnicotinamide, or butyraldehyde, each of which is an electron donor of aldehyde oxidase, under anaerobic conditions. The activity was inhibited by menadione, beta-estradiol, and chlorpromazine, which are inhibitors of aldehyde oxidase. The activities in the fish livers were similar to those of rat liver. Aldehyde oxidase purified from the livers of sea bream and rats exhibited the reducing activity. Thus, fenthion and fenthion sulfoxide are interconvertible in fish and rats through the activities of cytochrome P450, flavin-containing monooxygenase, and aldehyde oxidase.  相似文献   
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53.
We analyzed long-term treatment results in 51 patients with locally advanced uterine cervical carcinoma (IIB, 4; IIIB, 43; IVA, 4) treated with neoadjuvant intra-arterial (I-A) chemotherapy (cisplatin) via the uterine artery and irradiation. Thirty patients (58.8%) developed recurrence. Twelve had pelvic recurrence alone, 8 had distant metastases alone, and 10 had both pelvic and distant failure. The 5-year cumulative pelvic control rate, absolute survival rate, and disease-free survival rate were 55.3, 47.1, and 39.4%, respectively. Eight of 51 patients (15.7%) suffered late complications. These results suggest that our neoadjuvant I-A chemotherapy prior to irradiation has limited additional value for long-term prognosis in patients with locally advanced uterine cervical carcinoma.  相似文献   
54.
The biologic properties of adenomyosis and the effects of therapeutic agents on adenomyosis were evaluated with immunohistochemistry, terminal deoxy-nucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method, transmission electron microscopy, and analysis of genomic abnormality. In the adenomyotic endometrium, estrogen receptor (ER) expression was more intense than in the eutopic endometrium during the secretory phase, and bcl-2 was constantly expressed throughout the menstrual cycle. The expression of ER and bcl-2 was weaker in the adenomyotic endometrium treated with danazol than in that treated with gonadotro-pin-releasing hormone agonist (GnRHa), whereas bcl-2 phosphorylated on serine-87 was more intensely expressed in danazol-treated adenomyotic endometrium than in the GnRHa-treated one. The number of TUNEL-positive cells increased in the adenomyotic endometrium treated with danazol or GnRHa. Ultrastructurally, most of the adenomyotic endometrial cells treated with danazol underwent postapoptotic necrosis and formed a cluster of dead cells. In contrast, cells treated with GnRHa underwent typical apoptosis and were sparsely distributed in the adenomyotic endometrium. Analysis of several cancer-related genes showed no microsatellite instability or loss of heterozygosity in adenomyotic tissues. Therefore, we conclude that the occurrence of adenomyosis is correlated to bcl-2 expression regulated by estrogen and ER rather than genetic mutation.  相似文献   
55.
OBJECTIVE: To show the positional nystagmus in a patient who had suffered from benign paroxysmal positional vertigo (BPPV) that was thought to be caused by involvement of the anterior semicircular canal (ASCC) (A-BPPV). STUDY DESIGN: Retrospective case report. SETTING: City hospital. PATIENT: The present study reports a rare case of A-BPPV in a 41-year-old woman. CASE REPORT: The patient is 41-year-old woman who developed a positional vertigo after playing volleyball on March 22, 2005 and consulted our hospital the next day. When left Dix-Hallpike maneuver was performed, she showed a positional nystagmus of which fast phase direction of the torsional component was clockwise while that of the vertical component was downward. We plotted the slow phase eye velocity of the positional nystagmus during the left Dix-Hallpike maneuver on three-dimensional coordinates that showed the axis of the positional nystagmus to be perpendicular to the plane of the right ASCC. CONCLUSION: These results suggested that the patient was suffering from A-BPPV.  相似文献   
56.
The gut microbiota is closely related to good health; thus, there have been extensive efforts dedicated to improving health by controlling the gut microbial environment. Probiotics and prebiotics are being developed to support a healthier intestinal environment. However, much work remains to be performed to provide effective solutions to overcome individual differences in the gut microbial community. This study examined the importance of nutrients, other than dietary fiber, on the survival of gut bacteria in high-health-conscious populations. We found that vitamin B1, which is an essential nutrient for humans, had a significant effect on the survival and competition of bacteria in the symbiotic gut microbiota. In particular, sufficient dietary vitamin B1 intake affects the relative abundance of Ruminococcaceae, and these bacteria have proven to require dietary vitamin B1 because they lack the de novo vitamin B1 synthetic pathway. Moreover, we demonstrated that vitamin B1 is involved in the production of butyrate, along with the amount of acetate in the intestinal environment. We established the causality of possible associations and obtained mechanical insight, through in vivo murine experiments and in silico pathway analyses. These findings serve as a reference to support the development of methods to establish optimal intestinal environment conditions for healthy lifestyles.  相似文献   
57.
It has previously been reported that magnolol, a phenolic compound isolated from Magnolia obovata, inhibited tumour cell invasion in vitro. The purpose of this study was to investigate the antimetastatic effect of magnolol on tumour metastasis in vivo with experimental and spontaneous metastasis models and to clarify the mechanism. The antimetastatic effects of magnolol were evaluated by an experimental liver and spleen metastasis model using L5178Y-ML25 lymphoma, or an experimental and spontaneous lung metastasis model using B16-BL6 melanoma. Intraperitoneal (i.p.) administration of 2 or 10 mg/kg of magnolol significantly suppressed liver and spleen metastasis or lung metastasis. As for the spontaneous lung metastasis model using B16-BL6 melanoma, multiple i.p. administrations of 10 mg/kg of magnolol after and before tumour inoculation significantly suppressed lung metastasis and primary tumour growth. In addition, magnolol significantly inhibited B16-BL6 cell invasion of the reconstituted basement membrane (Matrigel, MG) without affecting cell growth. These data from the in vivo experiments suggest that magnolol possesses strong antimetastatic ability and that it may be a lead compound for drug development. The antimetastatic action of magnolol is considered to be due to its ability to inhibit tumour cell invasion.  相似文献   
58.
Lineage switch is a rare event at leukemic relapse. While mostly known to occur in KMT2A‐rearranged infant leukemia, the underlying mechanism is yet to be depicted. This case report describes a female infant who achieved remission of KMT2AMLLT3‐rearranged acute monocytic leukemia, but 6 months thereafter, relapsed as KMT2AMLLT3‐rearranged acute lymphocytic leukemia. Whole exome sequencing of the bone marrow obtained pre‐post lineage switch revealed two somatic mutations of PAX5 in the relapse sample. These two PAX5 alterations were suggested to be loss of function, thus to have played the driver role in the lineage switch from acute monocytic leukemia to acute lymphocytic leukemia.  相似文献   
59.
60.
TEX101 was characterized as a unique germ cell marker molecule using the specific monoclonal antibody (mAb), TES101. Although this mAb has strong affinity/specificity for TEX101, TES101 mAb loses its reactivity under reducing conditions. In this study, we have generated new mAbs against TEX101 to compensate for the shortcomings of the TES101 mAb using different approaches. First, we immunized mice with the antigen on a baculovirus expression system and isolated new anti-TEX101 mAbs, 6002 and 6035. Second, we raised the mAb Ts4 from spleen cells of an immunologically naive old mouse. Western blot analysis revealed that the new mAbs possess immunoreactivity under reducing/non-reducing conditions. Immunopositive staining of the mAbs against Bouin-fixed sections was observed in spermatocytes, spermatids and testicular spermatozoa, but not in other cells, similar to paraformaldehyde (PFA)-fixed frozen sections stained with TES101 as previously reported. However, whereas the mAbs 6002/6035 mainly showed immunoreactivity only in spermatocytes in PFA-fixed frozen sections, the reactivity of the mAbs to spermatids and testicular spermatozoa was clearly recovered when the PFA-fixed sections were autoclaved or treated with SDS. Peptide mapping and deglycosylation analysis indicated that the epitopes for TES101, 6002 and 6035 are located within TEX101(25-94), whereas Ts4 recognized N-linked carbohydrate moieties on TEX101 in Triton X-100-soluble mouse testicular extracts but not in the extracellular or water-soluble fractions. These results suggest strongly that the molecular association or structure of N-linked carbohydrate moieties of TEX101 varies according to its subcellular localization within the seminiferous tubules. These new mAbs will be valuable tools for further analysis of TEX101, including its function(s).  相似文献   
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