Systemic hypertension as a risk factor for complications with an aortic mechanical valve

We sought to determine the effect of preoperative systemic hypertension on prosthesis related complications or postoperative aortic dissection after valve replacement in patients with aortic regurgitation. The patients were divided into two groups according to the presence or absence of systemic hypertension: Group I, with hypertension (n = 35), and Group II, without hypertension (n = 37). The survival rate and event free rate were examined for 72 patients who were alive 30 days after valve replacement with a St. Jude Medical valve for aortic regurgitation. The cumulative 10 year survival rate of Group I (65% +/- 12%) was lower than that of Group II (79% +/- 15%). The 10 year event free rate of all prosthesis related complications was 62% +/- 13% in Group I, and 96% +/- 3% in Group II (p < 0.05). The 10 year event free rate for ascending aortic dissection was 73% +/- 12% in Group I and 100% in Group II (p < 0.05). The linearized event rate of all prosthesis related complication was 3.8% per patient-year in Group I and 0.5% per patient-year in Group II. In conclusion, systemic hypertension was a risk factor for prosthesis related complications and for complicated aortic lesions after aortic valve replacement. Careful postoperative management for hypertension is necessary in patients with systemic hypertension after aortic valve replacement. Tissue valves may be recommended in patients with aortic valve disease and severe hypertension.     

Alteration of drinking pattern after the entrance of university

Three hundred fifty-nine freshmen and freshwomen of Tokai University and Tamagawa University were examined for alcohol habituelle using questionnaires on life style and club activity as well as the established questionnaires of the Adolescent Alcohol Involvement scale (AAIS). The scores of AAIS of the male and female students were 30.6 and 27.7, respectively. About 10% of the subjects were revealed to be alcohol misusers. In both sexes, the drinking patterns remarkably changed after the entrance of university. Even in females, the drinking pattern markedly changed. The grade of club activity is one of factors influencing the drinking pattern of students. Especially big changes were observed in the students of cultural clubs.     

The effect of probucol on intimal thickening of autologous vein grafts in hyperlipidemic rabbit

OBJECTIVE: To define whether there is any relation between the iron status of patients with hepatitis C virus (HCV) chronic liver disease and their response to interferon therapy. DESIGN: To evaluate the long-term response to 1 year of interferon therapy with addition of phlebotomies after 3 months of treatment if at that time alanine aminotransferase (ALT) had not normalized in a group of patients with HCV-positive chronic liver disease whose iron status had been characterized. SETTING: A northern Italian hospital. PARTICIPANTS: Fifty-eight anti-HCV-positive patients (four HCV-RNA negative) with biopsy proven chronic hepatitis and no evidence of iron overload as indicated by normal transferrin saturation at the time of enrollment in the study. INTERVENTION: Three times a week intramuscular injection of alpha interferon 3 MU for 1 year with addition of phlebotomies (350 ml/week) till iron depletion if after 3 months of interferon therapy ALT had not normalized. RESULTS: A long-term response was observed in 19 of the 52 patients who completed the treatment, four HCV-RNA negative and 15 positive. The four RNA-negative and seven of the 15 RNA-positive long-term responders had been treated with interferon alone, and the other eight also with phlebotomies. At univariate analysis only HCV genotype, gamma-glutamyltranspeptidase and liver iron concentration were significantly associated with response whereas sinusoidal iron deposition was of borderline significance. No association was found with sex, age, duration of disease, histology, Knodell score, transferrin saturation %, serum ferritin, hepatocytic iron score, and portal iron score. HCV-RNA serum levels, measured in 29 patients, did not correlate with response. At multivariate analysis liver iron concentration was still significant and one unit reduction of liver iron concentration (natural logarithm transformed) was associated with 2.95 odds ratio of response. CONCLUSION: These results indicate that iron in the liver is more closely related to response to interferon than the other variables considered, including HCV characteristics.     

Surface properties and catalytic activities of amorphous niobium phosphate and a comparison with those of H3PO4-treated niobium oxide

Amorphous niobium phosphate was prepared by addition of phosphoric acid to an aqueous solution of potassium niobate. The surface property of the amorphous phosphate was highly dependent on degrees of aging of the precipitate and ranoval of K⁺ contaminant. As well as the phosphoric acid-treated Nb₂O₅) the amorphous phosphate was active as a catalyst for some acid-catalyzed reactions such as MTBE synthesis, esterifications using acetic acid, and alkylations of benzene.     

Characteristics of buried-channel pMOS devices with shallowcounter-doped layers fabricated using channel preamorphization

Channel preamorphization, which is a technique used for shallow boron counter doping of pMOSFETs to suppress short-channel effects, improves gate oxide quality in MOS capacitors with the field-edge structure. This indicates that the source of gate oxide quality degradation is located near the field oxide edge, and is eliminated in channel preamorphization process by the gettering effects of defects induced near the original amorphous/crystalline interface. The leakage current of junction diodes, on the other hand, is increased by channel preamorphization. The leakage current increases because the defects near the original amorphous/crystalline interface act as generation centers in the depletion layers. This problem will be overcome by increasing the preamorphization depth. Hot carrier immunity of pMOSFETs is improved by channel preamorphization, especially in short-channel devices     

EXAFS characterization and selective olefin hydroformylation on Rh4, Rh2Co2 and RhCo3 carbonyl clusters attached to tris-hydroxymethylphosphine-grafted silica

Rh_4-xCo_x(CO)₁₂ (x = 0, 2, 3) are attached by carbonyl substitution to THP (tris-hydroxymethylphospine)-grafted silica keeping their cluster frameworks. They have been characterized by Rh K-edge EXAFS (extended X-ray absorption fine structure) and Fourier transform IR spectroscopy. They exhibited high catalytic activity with > 98% selectivity in gas phase hydroformylation of ethene and propene to give aldehydes under mild conditions (40 kPa and 300–373 K).On leave from Research Center, Arakawa Chemical Industries, LTD, Tsurumi, Osaka 538, Japan.On leave from Department of Chemistry, National University of Literal, Santiago del Estero, 2829-3000, Santa Fe, Argentina.     

Effects of aging on urinary secretion of 3-hydroxyproline and its importance for cancer screening in the elderly with ROC analysis

OBJECTIVE: to observe the influence of aging on urinary secretion of 3-hydroxyproline (3-Hyp) in normal subjects and in cancer patients and study the effects of aging on the accuracy of urinary 3-Hyp as a general-purpose cancer screening test. DESIGN: We reanalyzed, from the aspect of gerontology, the amounts of 3-Hyp in the urine samples of the 211 healthy persons and 94 patients with cancer reported earlier. The two groups were divided in 3 age subgroups: adult, 30 to 44 years, middle-aged, 45 to 64 years, and aged, 65 years and older. The cancer stage was separated into 3 categories: stage 1, the early stage without any invasion, stage 2, locally invasive with no distant metastasis, and stage 3, advanced cancer. The correlation of age and urinary 3-Hyp was analyzed in normal subjects and cancer patients. Sensitivity and specificity were calculated for different cutoff points in the diverse groups to construct the receiver operating characteristic (ROC) curves. MAIN RESULTS: We observed that aging decreases the urinary secretion of 3-Hyp in normal subjects, with a correlation coefficient of -0.250 (p < 0.001). The mean levels of urinary 3-Hyp in patients with cancer were significantly higher than in the normal subjects, p = 0.005. The correlation coefficient of urinary 3-Hyp and age was not significant (0.100) in cancer patients. The cutoff points of 0.800 mg/g creatinine of urinary 3-Hyp for persons under 65 years of age and 0.600 mg/g creatinine for persons 65 years or older were the best thresholds for cancer screening. In the ROC analyses, we observed that 3-Hyp has higher accuracy for cancer screening in the aged group for all stages together and in the aged and middle-aged for early stages of cancer. CONCLUSIONS: The urinary 3-Hyp test was more effective for cancer screening in old persons (65 years or older), where cancer is more frequent and more difficult to discover. The authors stress the necessity and importance of verifying the effectiveness of urinary 3-Hyp for general cancer screening in a larger population and in a community set.     

Evaluation of a copper metallization process and the electricalcharacteristics of copper-interconnected quarter-micron CMOS

Copper metallization was applied to quarter-micron CMOS circuits using copper chemical vapor deposition (CVD) and chemical mechanical polishing (CMP). Both the metallization process and the electrical characteristics of CMOS devices/circuits were evaluated. Process-induced metal contamination on both sides of the wafer were quantitatively evaluated and reduced to about of 10¹¹ atoms/cm² by using an optimized cleaning sequence. The ability of borophosphosilicate-glass (BPSG) to act as a copper diffusion barrier was discovered and the ability of TiN to do so was also confirmed. Electrical characteristics of n and p MOSFET's with copper interconnections were stable even after annealing at 550°C. The leakage current of the pn junction, capacitance-voltage characteristics and time-dependent dielectric breakdown characteristics of the MOS diode indicate that the copper metallization process did not deteriorate the pn junction and the gate oxide. Normal operation of a 53-stage quarter-micron CMOS inverter ring oscillator with copper metallization was successfully achieved     

Molecular epidemiology of breast cancers in northern and southern Japan: the frequency, clustering, and patterns of p53 gene mutations differ among these two low-risk populations

Comparison of acquired mutations in the p53 tumor suppressor gene can illuminate factors contributing to carcinogenesis among cancer cohorts. Japan has an ethnically homogeneous population with a low incidence of breast cancer. Previously we reported an unusual frequency, allelic status, and clustering of mutations in breast cancers from the northern part of the main Japanese island. To extend these findings, exons 2-11 and adjacent intronic sequences were analysed in tumors of women from northern (Hokkaido) and southern (Tokushima) Japan. The frequency of breast cancers with p53 gene mutations in the Hokkaido group is the highest reported (81%) while that in Tokushima (28%) is similar to most other populations. Thirteen of the 19 mutations (68.4%) in the Hokkaido cohort were heterozygous, an unusually high frequency for p53 mutations in any tumor type. There were three missense mutations at codon 175, a known hotspot for alterations in the p53 gene, and three missense mutations at codon 179, a rare site for p53 changes. In addition, the patterns of p53 gene mutation differed between the two Japanese cohorts (P=0.04). The multiple differences in acquired p53 mutations suggest unsuspected biological differences among breast cancers in northern and southern Japan. In addition, the high frequency of p53 mutations in breast cancers from Hokkaido predicted a poorer prognosis for this population which was confirmed on examination of mortality data.