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1.
We examined the mechanisms of the inhibition of DNA synthesis by a new platinum compound, (-)-( R )-2-aminomethylpyrrolidine(1,1-cyclobutane-dicarboxylato)-2-platinum(II) monohydrate (DWA-2114R), a derivative of the antitumor drug cis- diamminedichloroplatinum(II) (CDDP), using prokaryotic and eukaryotic DNA polymerases. Preincubating activated DNA with CDDP or DWA-2114R reduced its template activity for prokaryotic and eukaryotic DNA polymerases in a dose-dependent manner. DWA2114R required six times greater drug concentration and two times longer incubation time to show the same decrease of the template activity compared to CDDP. Treatment of primed pUC118 ssDNA templates with the two drugs followed by second-strand synthesis by prokaryotic and eukaryotic DNA polymerases revealed that DWA2114R bound to DNA in a similar manner to CDDP and these adducts blocked DNA elongation by DNA polymerases of eukaryotes as well as of prokaryotes. With these two drugs, the elongations by E. coli DNA polymerase I (Klenow fragment), T7 DNA polymerase and calf thymus DNA polymerase α were strongly arrested at guanine-guanine sequences (GG). Stop bands were also observed at adenine-guanine sequences (AG) guanine-adenine-guanine sequences (GAG) and mono-guanine sequence (G). Calf testis DNA polymerase β was also arrested efficiently at AG, GAG and G, but much more weakly at GG. This pattern was common to DWA2114R and CDDP.  相似文献   
2.
A 16-year-old man was admitted to our hospital with nausea, general fatigue, and consciousness disturbance along with extreme hyperammoniemia eight days after the onset of symptoms. Familial history and the high concentration of orotic acid in urine lead us to a diagnosis of OTCD. We immediately initiated intensive treatment such as continuous hemodiafiltration and sodium benzoate administration; however, the patient died twelve days after admission. Since OTCD is not so rare and can be found in all ages, it should be considered fundamental for evaluation of hyperammoniemia. This case suggested that for a better prognosis of OTCD patients it is very important to prevent such an onset, and to make an as early as possible diagnosis and start to treatment.  相似文献   
3.
The effect of UV irradiation on bovine lens soluble proteins (crystallins) in the presence of tryptophan metabolites was investigated in vitro. The cross-linking of crystallins by UV irradiation was accelerated by kynurenine, 3-hydroxykynurenine, anthranilic acid and 3-hydroxyanthranilic acid. On denaturation of crystallins by photooxidation, alpha-crystallin was characterized by the formation of water-soluble HMW (high molecular weight) protein, while water-insoluble HMW protein was produced from beta- and gamma-crystallin. These HMW aggregates showed cross-linking by non-disulfide covalent bonds. LMW (low molecular weight) peptides were formed by degradation of alpha- and beta-crystallin.  相似文献   
4.
A series of 8 rat and 16 mouse invasive bladder carcinomas were investigated for the presence of silverstained nucleolar organizer regions (AgNORs) to clarify whether this parameter is applicable to the estimation of their invasive character. With regard to number of AgNORs per cell, neither rat nor mouse carcinomas showed any difference between invasive and noninvasive sites within the same tumor. However, the frequency of cancer cells bearing bizarre dots, irregular in size and shape, was significantly higher at sites of actual invasion. Quantitative data generated using an image analyzer revealed significantly lower values for NOR roundness and significantly larger NOR size in invasive sites than in noninvasive sites in all groups. Double staining for the proliferation marker proliferating cell nuclear antigen (PCNA) and AgNORs was performed on eight rat carcinomas and a close correlation between the two was confirmed. Thus the number of AgNORs in PCNA-positive cells was significantly greater than in PCNA-negative cells. Furthermore, a particularly strong correlation was observed for incidences of PCNA-positive cells and bizarre dots (P<0.01). The quantitative data also demonstrated significant differences in size and shape of dots. It is concluded that AgNORs have diagnostic value for the invasive character of bladder carcinomas.  相似文献   
5.
Effects of repeated testing on the incidence of haloperidol-induced catalepsy were investigated in mice. The incidence of catalepsy, evaluated with the forelimbs or hindlimbs placed on a standard horizontal bar, increased in three successive tests in mice injected with haloperidol. Catalepsy was not provoked by repeated testing in animals with saline. In a subsequent study, mice were examined for catalepsy in the forelimbs in the first two trials and then in the hindlimbs. In this procedure, the incidence of catalepsy did not increase with repeated testing. These results suggest that repeated testing increases the incidence of haloperidol-induced catalepsy but does not influence the cataleptogenic potency of the drug.  相似文献   
6.
The pathogenesis and etiology of Kawasaki disease are unknown, but some studies suggest increased genetic susceptibility. The case is presented of an infant with Kawasaki disease whose father suffered from the same illness 21 years previously. The A, B and C loci of the HLA antigens were examined.  相似文献   
7.
8.
A 51-year-old man was admitted because of hemoptysis. Physical examinations and chest XP revealed no abnormal findings. Fiberoptic bronchoscopy showed pulsatile bleeding at the orifice of right B6. Right bronchial arteriography showed a markedly dilated and tortous bronchial artery and shunting to the pulmonary arterial system in the middle and lower lobes. Pulmonary arteriography showed complete obstruction of the right middle lobar and lower lobe segmental arteries (A6, 9, 10). The hemoptysis was thought to be due to increased blood flow of the right bronchial artery, which compensated for reduced right pulmonary arterial flow. Right middle and lower lobe resection was done to prevent further hemoptysis. The resected specimen revealed old thromboemboli in the right middle and lower lobe pulmonary arteries. In this case old pulmonary embolism should be considered as a cause of intrabronchial bleeding.  相似文献   
9.
International discussions concerning rhinomanometry have been held but no numerical comparisons have been reported. In an attempt to make international comparisons between different rhinomanometric results, nasal resistances were measured by active posterior rhinomanometry with a head-out body plethysmograph produced in Canada and by active posterior and anterior methods with a Japanese commercial rhinomanometer, and the results were compared. No significant differences were found between measurements obtained from the two types of equipment. It is believed that this study is the first project of international comparison of rhinomanometry.  相似文献   
10.
The authors recently experienced a case of idiopathic interstitial pneumonia (IIP) that exhibited skin ulcers due to increased heparin precipitable fraction (HPF) in plasma. This case prompted us to investigate the occurrence and significance of HPF in interstitial pneumonia (IP). The subjects included patients with IIP (acute exacerbation 6 cases, chronic active stage 12 cases), IP associated with collagen vascular disease (CVD) (9 cases) and granulomatous lung diseases (7 cases). The data indicated that all of the cases with acute exacerbation of IIP exhibited increased plasma HPF values (218-951 mg/dl) compared to those of normal controls (less than 180 mg/dl). In contrast, the values ranged within normal limits in all of the cases with IP associated with CVD. In a companion study, we measured plasma HPF values in patients with lung cancer, bacterial pneumonia and diffuse panbronchiolitis. It was found that 22% of the subjects showed increased plasma HPF values. We also investigated whether there were correlations between plasma HPF and various inflammatory parameters. The data revealed that there were correlations between HPF and ESR, CRP, alpha 1-globulin, alpha 2-globulin, complement (C3) or fibrinogen. However, there was no correlation between HPF and fibronection. These results suggest that plasma HPF is valuable to evaluate the acute exacerbation of IIP, although the elevation of plasma HPF levels is not specific.  相似文献   
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