New developments in intravascular ultrasound

Intravascular ultrasound (IVUS) is a dynamic imaging modality that provides real-time in vivo visualization of atherosclerosis and other vascular pathology. The tomographic image presentation of IVUS permits detailed assessment of plaque morphology and its corresponding responses to interventional therapy. IVUS studies have confirmed vascular remodeling in vivo, have proposed a high-pressure stent implantation strategy and have shown two key mechanisms of restenosis after angioplasty: plaque proliferation and vessel shrinkage (negative remodeling). IVUS also provides accurate quantitative information regarding lumen size, vessel size and plaque burden. These observations, essential to achieving improved outcomes, have drastically changed the understanding of atherosclerotic artery disease and interventional procedures. IVUS has matured into an essential complement to daily peripheral and coronary interventional practice and is routinely incorporated as part of the interventional arsenal in the catheterization laboratory. A variety of new imaging techniques are currently being designed and tested. These include combined therapeutic devices, further miniaturization, 3-D applications and tissue characterization. These techniques may evolve to provide increased favorable clinical outcomes and more accurate information of vessel geometry and plaque composition.

[Aggressive diagnostic and therapeutic approach for acute coronary syndrome]

The purpose of this article is to propose an "aggressive strategy" in the treatment of patients with acute coronary syndrome (ACS), especially unstable angina. The indication and timing of emergent coronary angiography in patients with ACS remains to be validated. The results of TIMI III B trial, a randomized, controlled trial about this issue, show that an early invasive strategy reduced the average length of initial hospitalization and the incidence of rehospitalization within 6 weeks. However, the same kind of clinical trial named VANQWISH reported that no benefit was obtained from such an aggressive strategy. It is of paramount importance to note that these 2 studies were performed in the era of plain old balloon angioplasty. Now we can use many kinds of coronary stent which impart both excellent radial strength and flexibility. Recent studies have demonstrated that culprit lesions of ACS can be treated at the same success rate as those of stable effort angina. In our hospital, use of coronary stents in patients with ACS dramatically reduced the recurrence of ACS and the incidence of angiographic restenosis with the same initial procedure success rate. Since the mid-nineties, the radial artery has been used as a vascular access site of coronary intervention. The major advantage of this technique is lesser access site-related complications and increased patient comfort, which reduced hospital stay and cost. Recently it was demonstrated that ad-hoc transradial intervention can be applied in patients with unstable angina or even those with acute myocardial infarction by trained angioplasters. Thus, we would like to conclude that the best strategy in the management of ACS is to perform emergent coronary angiography from the radial artery as soon as possible after admission, and to do ad-hoc intervention using coronary stents suitable for the lesion anatomy.

Risk factors for breast cancer in Japan, with special attention to anthropometric measurements and reproductive history

BACKGROUND

Breast cancer incidence has increased rapidly in Japan recently, but there have been only a few studies on the risk factors for breast cancer in Japan. A case-control study was conducted to evaluate the roles of anthropometric and reproductive factors in the etiology of breast cancer in Osaka.

METHODS

Based on information from a self-administered questionnaire at Osaka Medical Center for Cancer and Cardiovascular Diseases, body mass index, body weight and height were compared between 376 cases and 430 controls, together with other factors such as age at menarche, age at first delivery and family history of breast cancer by menopausal status. Logistic regression analysis was employed for adjusting confounding factors and estimating odds ratios with their 95% confidence interval for breast cancer.

RESULTS

A body mass index of >25 was significantly associated with the risk among post-menopausal women (age-adjusted odds ratio: 1.90, 95% confidence interval: 1.10-3.24) as compared with the risk for a body mass index of < or = 20. A weight of > or =58 kg showed significantly increased risk compared with a weight of < or = 47 kg among post-menopausal women (1.83, 1.10-3.01), while height of > or = 159 cm showed a significantly elevated risk than height of < or = 149 cm among pre-menopausal women (2.51, 1.17-5.39). Age at menarche of < or = 13 years resulted in a higher risk of breast cancer among post-menopausal women, while age at first delivery of > or = 28 years was associated with the risk among pre-menopausal women. Family history of breast cancer was associated with the risk for breast cancer.

CONCLUSIONS

These results were all very consistent with findings observed in western countries.

Trends of lung cancer incidence by histologic type: a population-based study in Osaka, Japan

We investigated trends of lung cancer incidence from 1974 to 1993 by histologic type, using data from the population-based cancer registry in Osaka, Japan. Since the proportion of cases with histologic types identified was not sufficiently high, sex- and age-specific incidence rates by histologic types were estimated assuming that the distribution of histologic types was the same across the same sex and age group regardless of reporting status. Cumulative risk from 0 to 74 years old for total lung cancer increased 1.3-fold from the period 1974-77 to 1986-89 and then plateaued in the period 1990-93 for both males and females. When divided into histologic types, cumulative risk for incidence of squamous cell carcinoma was almost constant during the study period for both males and females. During the same period, adenocarcinoma increased up to 1.4-fold for both males and females. This increase seemed to have reached a plateau recently for males, but not for females. Small cell carcinoma increased monotonously up to 1.6- to 1.7-fold for both males and females. Large cell carcinoma showed over 2-fold increase for both males and females; however, the estimates fluctuated due to the small number of cases. This study provides further evidence of a relative increase of adenocarcinoma compared to squamous cell carcinoma. Recent trends of tapering increase of lung cancer incidence should be confirmed by further observation.

Algorithm for the treatment of mood disorders in Japan

In order to establish algorithms for mood disorders in Japan, over 300 psychiatrists completed a questionnaire. They were asked to recommend various drug treatments for particular cases. The order in which the drugs were recommended was taken into consideration. References were made to the randomized double blind study conducted by the working group. Evidence was ranked according to its probability, with the addition of case reports and medical opinions, since conclusions derived from the randomized double blind study alone did not give a full representation. Japanese documentation was referred to as much as possible in order to represent Japanese characteristics. Algorithms were made for eight subtypes; acute mania, bipolar depression, mild or moderate, severe major depression, psychotic depression, rapid cycling bipolar disorder, dysthymic disorder and major depression with advanced cancer. Major depression and bipolar disorder algorithms are discussed in this paper. Clinical psychopharmacological evidence in Japan was insufficient to generate these algorithms for mood disorders. These algorithms may need revision according to future advances in clinical psychopharmacology. (Int J Psych Clin Pract 1999; 3: 277-285).

Effects of mass screening for neuroblastoma on incidence, mortality, and survival rates in Osaka, Japan

OBJECTIVES

To evaluate the effects of mass screening for neuroblastoma, time trends of incidence, mortality, and survival of neuroblastoma in Osaka Prefecture were analyzed.

METHODS

Data for this analysis was obtained from the population-based Osaka Cancer Registry. Time trends of incidence and mortality rates were analyzed by calendar year and by birth cohort. Survival was compared between before and after the introduction of systematic screening.

RESULTS

From 1970-94, 457 cases of neuroblastoma and 182 deaths from neuroblastoma were observed in Osaka. The annual age-standardized incidence rate per million children increased from 7.5 in 1970-84 to 20.5 in 1985-94, while the mortality rates did not differ between these two periods. Analysis by birth cohort showed that the incidence rate at 0 year of age per 100,000 live births increased from 2.30 in 1970-79 (unscreened) to 19.80 in 1988-89 (screening by high-performance liquid chromatography, HPLC). The incidence rate in children 1 and 2-4 years of age also increased according to the introduction of HPLC. The mortality rate in children 1-4 years of age per 100,000 live births slightly decreased from 3.87 in 1970-79 to 3.30 in 1988-89, which was presumed to be derived from the improvement in survival due to the progress in treatment.

CONCLUSIONS

It is strongly suggested that mass screening for neuroblastoma causes harm because of overdiagnosis, and it has little effect on decreasing the incidence and the mortality of neuroblastoma at 1-4 years of age.

The risk of hepatitis C virus infection among blood donors in Osaka, Japan

To estimate the risk of hepatitis C virus (HCV) infection among blood donors, we conducted a retrospective cohort study with 448,020 HCV-seronegative donors who donated blood more than once between February 1992 and July 1997 in Osaka (a total of 2,676,738 allogeneic blood donations). The donors were divided into four age groups according to the age at the initial donation: Group A (16-24 years), Group B (25-34 years), Group C (35-49 years) and Group D (50-64 years). Fifty-nine donors became infected with HCV among the 448,020 HCV-seronegative donors who donated blood more than once within a period of approximately five years. In a total of 1,095,668 person-years of observation (PYO), the incidence rate was 5.38 per 105 PYO, with the 95% confidence interval (95% C.I.) being 4.10 to 6.95. There was no significant difference in the incidence rate between males and females. Young donors between the ages of 16 and 24 (8.89; 95% C.I., 6.04 to 12.61) had a significantly higher incidence rate of HCV infection than donors between the ages of 35 and 49 (1.81; 0.67 to 3.95). The cumulative risk of HCV infection among donors between the ages of 16 and 64 was estimated to be 0.27% (95% C.I., 0.16 to 0.39) for males and 0.27% (95% C.I., 0.15 to 0.38) for females. Based on the recent age-specific incidence rate, the cumulative risk of HCV infection among blood donors was estimated to be about 0.3% in the Osaka district of Japan. The incidence rate differed among age groups, indicating that HCV infection is associated with age-related behaviors and the need for further epidemiological research towards the eradication of community-acquired HCV infection.

[Index for evaluating completeness of registration in population-based cancer registries and estimation of registration rate at the Osaka Cancer Registry between 1966 and 1992 using this index]

The quality of population-based cancer registries has been measured by the indices of the proportion of total incident cases (DCO%) registered by death certificate only (DCO), and the ratio of incidence to mortality (I/D ratio). Recently it has been recommended that DCO% should be used as an index for the reliability of diagnosing cancers and that the proportion of cases first notified via death certificate (DCN, DCN%) be used as an index for the completeness of registration. Parkin introduced a method to estimate the registration rate, the estimated proportion of the "true incidence" that are registered in population-based registries. We recommend a modified method for estimating the registration rate for cancer registries where DCN% is relatively high, as it is in Japan, as Parkin's method may overestimate the registration rate. The method is as follows: the registration rate = (1-DCN% x 1/D ratio)/(1-DCN%). The registration rates at the Osaka Cancer Registry between 1966 and 1992 were estimated using our method. During this period, the yearly registration rate was 74.6-78.4% for males and 69.1-73.3% for females. When the cancer cases were looked at according to site, the yearly registration rate was 74.2-81.6% for stomach cancer, 81.2-89.3% for lung cancer, and 71.3-76.9% for uterine cancer. These results show that the registration rate is high for cancers that have an unfavorable prognosis and low for cancers that have a favorable prognosis. We recommend that all cancer registries in Japan calculate the completeness of registration by utilizing DCN defined as the sum of DCO plus cases not reported as cancer but with supportive clinical information of such obtained through survey of the registry for DCN.

Evaluation of a smoking cessation program implemented in the workplace

This paper evaluates the effectiveness of a smoking cessation program, known as "Smoke Busters." A quasi-experimental design was used. The experimental group consisted of 35 workers (33 males and 2 females) who smoked and volunteered to take part in the program held at a chemical company. Thirty five age-, sex-, and job category-matched smokers who did not participate in the program were used as controls. The program consisted of 6 sessions held over a period of 6 months. The sessions were organized in a workshop style, with 6 groups, each consisting of 5-6 participants, meeting for 2 hr during working hours. The effectiveness of the program was evaluated by the abstinence rate among the participants at one year after the start of the program. The abstinence rates of the experimental group and control group were 22.9% and 5.7%, respectively. Thus net abstinence rate was 17.2%. Given that 13% is considered as a reasonable benchmark for assessing the effectiveness of smoking cessation programs based on the results of the studies conducted in North America, one-year abstinence rate of 17% in this study, though not statistically significant (0.05 < p < 0.1) encourages larger experiments.

[Analysis of adenovirus type 7 hexon hypervariable region]

The isolation of adenovirus type 7 (Ad7) has been rare in Japan in the past. However since April, 1995, many isolates of Ad 7 have been reported. In order to find the cause of Ad 7 re-emergence in Japan, we investigated the genome sequences of Ad 7 by analyzing the hexon hypervariable regions (HVRs). HVRs of genomes isolated before and after this prevalence showed little change and were closely related with each other. It was concluded that adenovirus hexon which contains HVRs is conserved in the same serotype of any genome type. At present, virus genome typing seems more suitable for comparing the differences of genomes than sequencing.

[Smoking behavior and cognition for smoking cessation after diagnosis of head and neck cancer or stomach cancer]

This study aims at describing smoking behavior and cognition for smoking cessation among Japanese men after the diagnosis of cancer. Subjects were 144 patients with head and neck cancer (oral cavity, pharynx and larynx without requirement of total laryngectomy) and 104 patients with stomach cancer who were current or ex-smokers at time of diagnosis. A self-administered questionnaire was mailed at least 1.5 years alter diagnosis. Response was by mail and 72% (248/344) of completed questionnaires were returned. Among 164 patients who were smokers at the time of diagnosis, 59(36%) reported that they continued to smoke after the diagnosis of cancer. Stomach cancer patients (53%) had significantly higher (p < 0.01) continuance rate of smoking than head and neck cancer patients (24%), and patients in fifties (53%) had the highest continuance rate of smoking in the study participants. Among 105 patients who were abstinent, 83(79%) had stopped smoking within 6 months after the diagnosis of cancer. Interest in smoking cessation among the current smokers was high (83%), and they preferred a smoking cessation class with multiple participants to "person to person" counseling provided by health care practitioners.

[Two cases of dermatophytosis of the external auditory meatus]

We report two cases of dermatophytosis of the external auditory meatus. Case 1: A 44-year-old man suffered from severe itching in the right external auditory meatus for a year, and had also had tinea unguium for several years. He visited our outpatient clinic because of scaly erythema which had developed on the auricle. Otoscopic examination revealed yellow-brown dry cerumen and redness from the cartilaginous to the bony portion of the external auditory meatus. Case 2: A 14-year-old boy, the son of Case 1, suffered from severe itching in the left external auditory meatus. He scratched the auditory meatus with an earpick which his father had used. Otoscopic examination revealed a similar lesion as in the father's case, although he had no history of dermatophytosis elsewhere on his body, including the auricle. Direct examination using a KOH method of the cerumen from both cases demonstrated numerous fungal elements. Fungal culture identified Trichophyton rubrum. Both cases were successfully treated with oral itraconazole. We suggest that infection from father to son was transferred by the earpick.

[GM1-gangliosidosis knockout mouse]

We generated a beta-galactosidosis mouse by gene targeting in an embryonic stem cell. Clinical, pathological, and biochemical analyses revealed that this mouse is a useful animal model to study the pathogenesis and therapy of human GM1-gangliosidosis.

Maturation and degradation of beta-galactosidase in the post-Golgi compartment are regulated by cathepsin B and a non-cysteine protease

Lysosomal beta-galactosidase precursor is processed to a mature form and associated with protective protein in lysosomes. In this study we used two cysteine protease proinhibitors, E64-d for cathepsins B, S, H, and L, and CA074Me for cathepsin B. They are converted intracellularly to active forms, E-64c and CA074, respectively. Both active compounds inhibited maturation of the exogenous beta-galactosidase precursor, but E-64c did not inhibit further degradation to an inactive 50-kDa product. We concluded that cathepsin B participated exclusively in maturation of beta-galactosidase, and a non-cysteine protease was involved in further degradation and inactivation of the enzyme molecule.

Up-regulation of oxygen-derived free radicals by interleukin-1 in hepatic ischemia/reperfusion injury

BACKGROUND

Oxygen-derived free radicals (FRs) are critical mediators of ischemia/reperfusion injury. Inflammatory cytokines have been shown to play important roles in tissue injury. To examine the relationship between FRs and interleukin-1 (IL-1) in hepatic ischemia/reperfusion injury, we used interleukin-1 receptor antagonist (IL-1ra) to block endogenous IL-1 production in a rat model of hepatic ischemia/reperfusion.

METHODS

Female SD rats were subjected to 30 min of hepatic ischemia followed by reperfusion. The animals were divided into two groups, control group and IL-1ra-treated group, according to the rinse solution. In both groups, FR production, histological changes, and interactions between leukocytes and endothelial cells were analyzed in the course of reperfusion.

RESULTS

In the control group, production of FRs increased significantly after 60 min of reperfusion. After 60 and 180 min of reperfusion, histological examination showed atrophy and degeneration of hepatocytes. Hepatic microcirculation demonstrated a marked increase in the number of leukocytes adherent to endothelial cells and of injured cells after reperfusion. In the IL-1ra-treated group, IL-1ra pretreatment markedly reduced FR production after 60 min of reperfusion, the number of leukocytes adherent to endothelial cells, and tissue injury.

CONCLUSION

These data clearly show an important role for IL-1 in the induction of FR production, leukocyte adhesion, and tissue injury after hepatic ischemia/reperfusion injury.