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1.
Direct measurement of intra-arterial blood pressure (BP) for 24-h provides approximately 100,000 values that vary enormously, but each (BPi) can be expressed by the equation BPi = BP0 + DeltaBPi (BP0, base BP; DeltaBPi, BP increment, i=1, 2, ..., 100 x 10(3)). About 20% of outpatients with hypertension exhibit white-coat hypertension (WCH). In such patients, DeltaBPc (i = c; c, time at the clinic) is surmised to be large. A method for explaining the physiological factors in DeltaBPc and the estimation of base BP in the outpatient clinic is important. This study addresses this issue. A total of 293 subjects were divided into four groups: 1) WCH group, 45 individuals (office BP > or = 140/90 mmHg and 24-h indirect BP < 125/80 mmHg); 2) normotensive (NT) group, 84 controls matched for age and sex; 3) WHO-I group, 95 hypertensive patients with WHO stage I (office BP > or = 140/90 mmHg and 24-h BP > or = 125/80 mmHg); and 4) WHO-II group, 69 hypertensive patients with WHO stage II. Their BPc and heart rate (HR; HRc, clinic HR) values were measured by a BP-ECG monitoring device in the outpatient clinic. Power-spectral analysis was used to obtain the ratio between the low-frequency component (LF) and high-frequency component (HF) of ECG-RR variability (LF/HF = LH). Twenty-four-hour indirect BP (and BP0) and base HR (HR0) were measured by a portable device (TM2425) at 30-min intervals. Then, DeltaBPc (= BPc - BP0) was estimated by performing linear multivariate analysis applying the model equation DeltaBPc = (BPc -alphaLH)(1-betaHR0/HRc) + epsilon to the above variables (alpha and beta, constant values; epsilon, error). This model equation made it possible to estimate BP0 (and DeltaBPc) with a high coefficient of correlation (r > or = 0.85, mean of error less than 0.82 +/- 5.9 mmHg). The predictive accuracy for discrimination between WCH and sustained hypertension (WHO-I and WHO-II groups) by this equation was 88%. The new DeltaBP-estimation device (BP-ECG monitor) enabled us to infer BP0 and is therefore useful in estimating WCH in the outpatient clinic.  相似文献   
2.
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   
3.
Advanced glycation end products are the chemical modification of proteins induced by sugars in a hyperglycemic condition. Extracellular matrix proteins are prominent targets of nonenzymatic glycation because of their slow turnover rates. The aim of this study was to investigate the influence of nonenzymatic glycation of type I collagen on the migration of keratinocytes. The migration of keratinocytes was dramatically promoted on native type I collagen-coated dishes compared with that on uncoated dishes. When type I collagen was glycated with glycolaldehyde, large amounts of advanced glycation end products were produced; the glycated collagen I-coated dishes did not promote the migration of keratinocytes. Glycated collagen I did not affect the proliferative capacity of keratinocytes. However, the adhesion of keratinocytes to glycated collagen I was profoundly diminished in a glycation intensity-dependent manner. alpha2beta1 integrin is responsible for the migration and adhesion of keratinocytes to type I collagen. Pretreatment with glycated collagen I did not affect the expression level or functional activity of alpha2beta1 integrin on keratinocytes. These findings suggest that in the presence of glycated collagen I, keratinocytes lose their adhesive and migratory abilities. As the glycation did not modify the alpha2beta1 integrin on keratinocytes, it is suggested that glycation may diminish the binding capacity of type I collagen.  相似文献   
4.
Classical citrullinemia (CTLN1), a rare autosomal recessive disorder, is caused by mutations of the argininosuccinate synthetase (ASS) gene, localized on chromosome 9q34.1. ASS functions as a rate-limiting enzyme in the urea cycle. Previously, we identified 32 mutations in the ASS gene of CTLN1 patients mainly in Japan and the United States, and to date 34 different mutations have been described in 50 families worldwide. In the present study, we report ASS mutations detected in 35 additional CTLN1 families from 11 countries. By analyzing the entire coding sequence and the intron-exon boundaries of the ASS gene using RT-PCR and/or genomic DNA-PCR, we have identified 16 novel mutations (two different 1-bp deletions, a 67-bp insertion, and 13 missense) and have detected 12 known mutations. Altogether, 50 different mutations (seven deletion, three splice site, one duplication, two nonsense, and 37 missense) in 85 CTLN1 families were identified. On the basis of primary sequence comparisons with the crystal structure of E. coli ASS protein, it may be concluded that any of the 37 missense mutations found at 30 different positions led to structural and functional impairments of the human ASS protein. It has been found that three mutations are particularly frequent: IVS6-2A>G in 23 families (Japan: 20 and Korea: three), G390R in 18 families (Turkey: six, U.S.: five, Spain: three, Israel: one, Austria: one, Canada: one, and Bolivia: one), and R304W in 10 families (Japan: nine and Turkey: one). Most mutations of the ASS gene are "private" and are distributed throughout the gene, except for exons 5 and 12-14. It seems that the clinical course of the patients with truncated mutations or the G390R mutation is early-onset/severe. The phenotype of the patients with certain missense mutations (G362V or W179R) is more late-onset/mild. Eight patients with R86H, A118T, R265H, or K310R mutations were adult/late-onset and four of them showed severe symptoms during pregnancy or postpartum. However, it is still difficult to prove the genotype-phenotype correlation, because many patients were compound heterozygotes (with two different mutations), lived in different environments at the time of diagnosis, and/or had several treatment regimes or various knowledge of the disease.  相似文献   
5.
BACKGROUND: The loop-mediated isothermal amplification (LAMP) method is a novel technique for the amplification of specific DNA sequences. OBJECTIVES: To establish the LAMP method for amplifying Epstein-Barr virus (EBV) DNA and to examine its reliability for the detection of EBV DNA in clinical specimens. STUDY DESIGN: Sera from 108 patients, who were initially suspected of primary EBV infection, were tested by the EBV LAMP method, and the results were compared with those of the real-time PCR assay. Serological examination was regarded as the standard diagnostic method. RESULTS: To diagnose primary EBV infection, the sensitivity of LAMP was 86.4% and the specificity was 100%. The sensitivity of the real-time PCR assay was 84.1% and the specificity was 98.4%. Longitudinal analysis showed that the detection rate of EBV DNA in serum by the LAMP method decreased with time in accordance with the decrease of the EBV load. EBV DNA could not be detected in serum 40 days after onset of symptoms. CONCLUSIONS: These results indicate that the sensitivity and specificity of the LAMP method are comparable to those of real-time PCR and that detecting EBV DNA in serum by this method is potentially useful for diagnosing primary EBV infection.  相似文献   
6.
Previously, we established the in vivo lung metastasis model of rat HCC induced by two hepatocarcinogens, diethylnitrosamine (DEN) and N-nitrosomorpholine (NMOR) at a dose of 120 ppm. This model allows us to investigate modifying factors leading to the inhibition of metastasis formation. However, low survival rates made the evaluation of metastasis formation difficult. The current experiments were conducted to modify the experimental protocol to improve survival and to establish a better animal metastasis model. Lower doses of NMOR (80 or 40 ppm in drinking water) were given to F344 rats for 14 weeks after DEN treatment. Survival rates in the 80 ppm group and in the 40 ppm group were 57% and 81%, respectively and these values were significantly higher than that in 120 ppm. Incidences of lung metastasis in the 40 ppm group steadily increased up to 67% by week 36 while that in the 80 ppm increased sharply up to 86% by week 24. Severity of lung metastases in the 40 ppm group at week 36 was mild compared with the 80 ppm group at week 24. In the second experiment, in order to characterize HCC development and lung metastasis in the 40 ppm group, rats given DEN and then followed with 40 ppm NMOR were killed sequentially. Development of HCC was observed at week 14 and reached 100% incidence at week 20. First lung metastatic lesions were evident at week 22, and incidence of lung metastasis reached 100%. Tumor cells were identified in the blood at week 20 by RT-PCR. The current study revealed that 40 ppm NMOR for 14 weeks after DEN treatment developed HCC without lung metastases at week 22, then HCC with a frequent lung metastasis at week 40. Thus, it can be said that this system is a more appropriate model for elucidation of mechanisms of metastasis and also for analysis of factors to inhibit natural metastasis.  相似文献   
7.
The dose-dependent effects of three hepatocarcinogens were investigated by measuring the number and area of glutathione S-transferase placental form (GST-P)-positive foci and nodules appearing in the liver under short-term conditions (Experiment I) and evaluating the incidence of hepatocellular carcinoma after long-term chronic administration (Experiment II). For these purposes, three different doses of 2-acetylaminofluorene (2-AAF), 3'-methyl-4-dimethy-laminoazobenzene (3'-Me-DAB), and DL-ethionine (ethionine) were given to male F344 rats for 6 weeks after a single injection of diethylnitrosamine (DENA) in Experiment I or for 104 weeks without initiation by DENA in Experiment II. In Experiment I, the induction of GST-P-positive foci and nodules by 2-AAF and 3'-Me-DAB was clearly dose-dependent. In contrast, ethionine showed enhancing effects inducing GST-P-positive foci and nodules only in groups given the highest dose level. Similarly, in Experiment II, induction of hepatocellular carcinomas by 2-AAF and 3'-Me-DAB was clearly dose-dependent, whereas liver neoplasms were only induced by the highest dose level of ethionine. These results indicate that degree of induction of GST-P positive foci and nodules in a short-term in vivo test for liver carcinogens corresponds with the incidences of hepatocellular carcinomas revealed in a long-term in vivo assay.  相似文献   
8.
The present experiment was undertaken to investigate possible synergism in induction of rat prostate tumor. F344 rats were repeatedly administered the prostate carcinogens 3,2'-dimethyl-4-aminobiphenyl (DMAB),N-nitrosobis(2-oxopropyl)amine(BOP), and N-methylnitrosourea (MNU) sequentially or together at times of hormonal castration induced regenerative cell proliferation of prostate epithelial cells. Group 1 animals received two 100 mg/kg doses of DMAB, two 20 mg/kg applications of BOP, and two times 15 mg/kg of MNU. Groups 2, 3, and 4, respectively, received each of the carcinogen treatment alone. Group 5 was given 6 applications of all three in combination, each at one-third the dose administered to the other groups. The results showed a clear synergism in enhanced tumor development in the colon but not in the prostate, in which the incidence of lesions induced by the three carcinogens was similar to that with DMAB alone.  相似文献   
9.
Sequential observations were carried out on the induction ofpreneoplastic lesions in the liver and the kidney. Rats wereinitially given N-ethyl-N-hydroxyethylnitrosamine (EHEN) intheir drinking water (0.1%) for 3 days (Group 1), 1 week (Group2) or 2 weeks (Group 3) or tap water (Group 4). Rats in Groups1 – 3 were subjected to partial hepatectomy and unilateralnephrectomy (right side) 2 weeks after the end of EHEN treatment.Rats from these groups were killed in week 10, 20, 30 and 40of the experiment. In the liver, the effect of EHEN in the inductionof -glutamyltranspeptidase (-GT) positive foci and hyperplasticnodules (HN) was clearly dependent on the length of treatment.The preneoplastic lesions increased with the lapse of observationtime. Changes measured as number of -GT positive foci were 10–40times greater than those measured as HN, especially among thesmall size range. Values for changes in Group 1 given 0.1% EHENfor 3 days were very low, indicating that this dose is closeto the threshold. Two rats with hepatocellular carcinoma inGroup 3 given EHEN for 2 weeks survived until week 40. In thekidney, tubular epithelial proliferations composed of cellswith slightly basophilic cytoplasm and slightly atypical nucleiwere tentatively named atypical cell foci (ACF). EHEN inducedACF, renal cell adenomas and renal cell carcinomas. The increasein the induction of ACF was dependent on the length of observationperiod but not on the length of treatment. Even though controlrats (not treated with EHEN) also had ACF, their quantitativevalues were far less than the groups given EHEN and killed atweek 40, indicating that a large number of ACF were inducedby EHEN. Therefore, EHEN is good for experimental inductionof preneoplastic lesions in the liver and kidney of rats. Theexperimental schedule for Groups 1 and 2 could be used as ashort-term screening test for promoters and the schedule forGroup 3 as an assay for inhibitors.  相似文献   
10.
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