Blood pressure levels in school-age Japanese children: the Hisayama Study

Blood pressure (BP) measurements were obtained on a total of 6325 children (3294 boys and 3031 girls), aged 6-14 years, in Hisayama, Japan. All BPs were recorded in a sitting position by trained observers in a standardised manner. Standard mercury sphygmomanometers were used with commercially available cuffs, selected according to the arm circumference. Cuff size no. 3 (bladder width 9 cm, length 23 cm) was the one most commonly selected in 84% of elementary schoolers aged 6-11 years and in 35% of junior high schoolers aged 12-14 years. Mean systolic BPs (SBPs) increased from 89 mm Hg at age 6 years to 108 mm Hg at 14 years (a 21% increase) for boys and from 88 mm Hg to 102 mm Hg (a 16% increase) for girls. Diastolic BP (DBPs, Korotkoff phase IV, KIV) increased from ages 6 to 14 years to the same degree, from 58 mm Hg to 72 mm Hg (a 24% increase) for boys and from 58 mm Hg to 70 mm Hg (a 21% increase) for girls. The increase in DBP (Korotkoff phase V, KV) was greater, from 48 mm Hg to 63 mm Hg (a 30% increase) for boys and from 48 mm Hg to 61 mm Hg (a 28% increase) for girls. The increase in mean SBP for adolescent boys was greater compared with that of girls; however, separation of age-specific values by sex was not observed for mean DBP (KIV) and DBP (KV). The cross-sectional relation between age and mean SBP levels was not linear.

Double chamber ventricular assist device with a roller screw linear actuator driven by left and right latissimus dorsi muscles

A double chamber ventricular assist device (VAD) with a roller screw linear muscle actuator (RSLMA) driven by the left and right latissimus dorsi muscles was developed. The inflow port of each chamber was connected to form the compound inflow port, and the outflow ports were connected to form the compound outflow port. The advantages of this system include 1) the contraction of each muscle contributes to ejection from each ventricle into the common outflow port, thus doubling the net outflow; 2) through proper adjustment of muscle length, the preload to each muscle can be optimized to yield the maximum muscle force; 3) muscle can be stimulated at a lower rate to reduce fatigue and to optimize muscle performance; and 4) the compliance chamber needed in the implantable VAD system is not required with this system. In vitro evaluation in the mock loop with the human arm actuating the RSLMA revealed that the double chamber VAD can provide pump flows of 2-4 L/min against an afterload of 100 mmHg at a stimulation rate of 35-50 beats per minute. The power requirement for each muscle ranged from 2.5 to 3 W at a muscle stroke length of 4 cm. These results verify that the double chamber VAD with the RSLMA driven by the left and right latissimus dorsi muscles can meet the design requirements of a muscle driven VAD to assist the left heart.

Prognostic factors of vision in patients with Behçet disease

BACKGROUND

Behçet disease is a chronic, recurrent, inflammatory disorder characterized by the triad of oral and genital ulcers and ocular lesions. The etiology is unknown. Although many of these patients become blind, some have good vision all their life.

METHODS

To attain more accurate data on the prognosis of these patients, the authors studied 52 Japanese patients (101 eyes) seen at Kyushu University Hospital between 1980 and 1990. At the first visit, patients ranged in age from 21 to 61 years; at onset, they ranged in age from 17 to 55 years; and the disease duration at first visit was from 0 to 22 years. Thirty-five of the 101 eyes had a visual loss of more than five lines or the patients became blind. The authors divided the subjects into two groups--favorable group and unfavorable group. If an eye had more than five lines of visual loss or the patient became blind 3 years after the first visit, it was placed in the unfavorable group, and if not, it was classed in the favorable group. Thirty-two factors determined from clinical records were used to select statistically significant risk factors for visual loss, using univariate analysis and multivariate logistic regression analysis.

RESULTS

Univariate analysis showed the following four factors that were significantly different between favorable and unfavorable groups: sex, disease interval, other complications, and skin lesions (first year). Multivariate analysis showed that the following seven factors had mutually independent contributions to visual loss: skin lesions; arthritis; posterior attacks; other complications (experienced), including gastrointestinal, vascular, and central nervous system lesions; female sex; disease interval; and anterior attacks. The first four factors have effects of losing vision, whereas the others are related to vision retention.

CONCLUSION

The authors find that skin lesions, arthritis, posterior attacks, and other complications are linked to loss of vision, whereas female sex, disease interval, and anterior attacks are related to retention of vision.

Cloned primed lymphocyte test cells recognize the fourth, fifth, and sixth hypervariable regions at amino acid positions 65-87 of the DPB1 molecule

Genetic polymorphisms of the HLA-DPB1 gene in Japanese and Caucasian panel cells defined by PLT were analyzed by the PCR-based genotyping technique PCR-RFLP, and suballeles of DPw3 (DPB1*03) and DP"Cp63" (DPB1*09) could be detected. PLT-defined DPw3 cells were typed by PCR-RFLP as either DPB1*0301 or DPB1*1401. On the other hand, PLT-defined DPCp63-typed cells were typed as DPB1*0901 or DPB1*1001. These results indicate that both DPw3 and DPCp63 are split into two subantigens. DPw2 and DPw4 are DPB1*0201 and 0202 and DPB1*0401 and 0402, respectively. Comparative analysis of the amino acid sequences of the DPw2-, DPw4-, DPw3-, and DPCp63-associated alleles revealed that the fourth (C), fifth (D), and sixth (E) hypervariable regions at amino acid positions 65-87 were shared within the same PLT-defined DP antigen groups, suggesting that these three hypervariable regions are recognized by cloned T cells in PLT, thus determining DP antigen specificity. On the basis of this model, 44 DPB1 alleles can be classified into 18 antigen groups, each of which may possibly represent a PLT-defined single DP specificity.

Longitudinal characteristic curve of liver disease

A longitudinal characteristic curve of chronic liver disease (LCC-LD) is derived for the first time by a new method of time series data analysis, where a hospital information system is utilized as a clinical research application of the database. It describes a typical pattern of development of disease from the beginning of chronic hepatitis to the final stage of cirrhosis. The LCC-LD is obtained by effectively using patient data with various stages of developments of liver disease and the present method is applicable to derive the LCC of other diseases. The obtained LCC-LD may be useful for a clinical decision making support such as the prospective assessment (for example, the onset time of cirrhosis) of liver disease in individual patients, an evaluation of drug effect, etc.

Relationship between intraocular pressure and age in the exfoliation syndrome

We examined the presence or absence of exfoliative material and measured the intraocular pressure (IOP) of 220 residents of a nursing home. The prevalence of the exfoliation syndrome increased with age and the IOP of persons with the exfoliation syndrome was higher than that of persons without the syndrome. In eyes with the exfoliation syndrome, the IOP had a tendency to decrease with increasing age. Aging had little influence on IOP in eyes without the exfoliation syndrome. There were significant differences between the two groups with regard to the effects of aging on IOP.

Agarose-carrageenan hybrid polysaccharides from Lomentaria catenata

Two polysaccharide fractions, PS1 and PS2 from Lomentaria catenata consisted of D-Gal, L-Gal, D-Glc, D-Xyl, D-GlcA and sulphate. Partial hydrolysis led to the isolation and identification of oligosaccharides indicating the co-existence of an agarose and carrageenan backbone structure, in which D-Glc and D-GlcA residues occur as single units branching at O-3 of -->4)alpha-D-Gal(1--> and O-4 of -->3)beta-D-Gal(1-->, respectively.

Patient registration and treatment allocation in multicenter clinical trials using a FAX-OCR system

This article describes the design and results of implementation of an automated patient registration and treatment allocation system (RETAS) used in multicenter clinical trials. RETAS was developed using a FAX-OCR system by which handwritten Japanese and English characters, as well as numericals and forms with check boxes, are sent from participating institutions by Fax, processed using an optical character reader, and then transmitted to a host computer at a statistical center. Based on the facsimile data, RETAS can automatically review eligibility, collect patient identification data and provide a randomized treatment allocation. RETAS permits uninterrupted, unattended operation at a statistical center, 24 hours a day, 7 days a week. Therefore, it drastically decreases the workload of personnel at the statistical center needed to support central telephone registration coverage. Consequently, staff members are free to focus on patient registration, treatment allocation, and follow-up of patients. The treatment allocation procedure in this system is based on Pocock and Simon's minimization method combined with Zelen's method for institution balancing. By this system it was possible to balance treatment numbers for each level of various prognostic factors over an entire trial and, at the same time, balance the allocation of treatments within an institution. The system currently supports the protocol of a clinical trial for Adjuvant Chemo-Endocrine Therapy for Breast Cancer in West Japan.

Microsoft Excel Program for creating attractive survival curves

This paper describes the design of a Microsoft Excel Program which interactively creates attractive and outstanding survival curves. This program enables medical researchers to easily create quality presentation graphs of survival curves and obtain high quality slides and prints, which can be inserted in papers or used directly at medical meetings. Through the use of vertical bars, this program can display the exact points where censored cases occur on survival curves, making it possible to monitor censoring patterns between groups. Furthermore, this program can also create survival curves based on the proportional hazards model for specific patterns of covariate values, given estimated regression coefficients and baseline survival function. This program may be a most useful and effective tool in creating medical research papers containing survival analysis.

The organization of statistical activities at medical research institutions

In this paper, we discuss the organizational structure for the conduct of statistical activities at medical Colleges and Universities. Here, we have particularly focused on two significant statistical activities, i.e., statistical consultation and research. The consulting service for medical researchers consists of practical statistical analysis, instruction on computer manipulation and software, response to reviewer's comments and statistical design of prospective studies. From our various experiences, we describe the actual implementation of statistical consultations for medical researchers. It has played an important role in supporting medical research. In addition, we also outline some research, with respect to new ways of applying statistics in medical science. This paper concludes that it may be practical for the existing computer center or department of medical informatics, in charge of the computing service, to conduct statistical activities until formal organizations are established at the academic institution. To realize the conduct of statistical activities by Department of Medical Informatics, it needs a team of biostatisticians, data analysts and computer personnel.

Molecular genetic studies of HLA class II alleles in sarcoidosis

Previous HLA serological studies showed positive associations of the DR52 antigen, the DR52-associated antigens (DR3, DR5 and DR6) and the DR8 antigen with sarcoidosis. To investigate the HLA alleles that may contribute to the genetic susceptibility to sarcoidosis at the DNA level, HLA-DRB1, -DRB3, -DQA1 and DQB1 genotyping using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was performed in 63 Japanese patients with sarcoidosis. The frequencies of the DR52-associated DRB1 alleles (DRB1*11, DRB1*12 and DRB1*14 except DRB1*1302), DRB1*08, DRB3*0101, DQA1*0501 and DQB1*0301 were significantly increased in patients compared with healthy controls. The significant increase of DRB3*0101, DQA1*0501 and DQB1*0301 could be explained by linkage disequilibrium with the DR52-associated DRB1 alleles. It must be noted that the DR8 haplotype, which does not possess the DRB3 gene, also showed a significant increase in sarcoidosis. These results suggest that the HLA-alleles responsible for the susceptibility to sarcoidosis are located at the HLA-DRB1 locus rather than the HLA-DRB3, -DQA1 and -DQB1 loci. In contrast, DRB1*1302 may confer resistance to the disease.

Estimation of risk of major complications after hepatic resection

To identify the risk factors predicting major postoperative complications from among preoperative and intraoperative variables, an extensive retrospective analysis of 209 patients who underwent hepatic resections was performed using multivariate logistic regression. The major complications were defined as liver failure, intractable ascites and pleural effusion, intraperitoneal infection, intra-abdominal hemorrhage requiring reoperation, major bile leakage, and gastrointestinal tract bleeding. First, detailed pre- and intraoperative data including medical history, laboratory data, portion and extent of hepatectomy, operative time, and amount of blood loss were univariately analyzed. Next, any significant variables were multivariately analyzed using the logistic regression method. Diabetes, increased intraoperative blood loss, resection of segment 8, and an increased serum blood urea nitrogen level were independent and significant variables predicting major postoperative complications. A higher level of serum cholesterol and a procedure involving a portion of left lateral segment were found to decrease the risk. Both more careful operative procedures and intensive management of DM and renal dysfunction in the perioperative period could result in a better quality of life after hepatic resection.

Long-term prognosis and prognostic factors of liver cirrhosis in the 1980s

The prognosis of 174 patients with cirrhosis during the 1980s (1981-89) was analysed. The estimated survival rates were 87.3% in 3 years and 68.5% in 5 years. During the follow-up period, 58 patients died: 20 of hepatocellular carcinoma (37.7%); 11 of hepatic failure (20.8%); eight of gastrointestinal bleeding (15.1%); and 14 of other causes (26.4%). Multivariate analysis revealed that serum albumin, indocyanine green retention rate at 15 min and white blood cell count were significantly associated with prognosis. The results were also compared to our previous study covering the 1970s (1971-80). The estimated survival rate was significantly improved compared to that during the 1970s (54.3% in 5 years, P < 0.001). In the 1980s, hepatic failure mortality significantly decreased (P < 0.01), and non-liver-related mortality significantly increased (P < 0.05). In summary, the prognosis of cirrhosis has improved in recent years, and changes of death cause and prognostic factors were observed. It was concluded that to evaluate the severity and prognosis of cirrhosis, new indices and appropriate classification were necessary.

A flexible random allocation program for multi-institutional clinical trials

This paper describes a flexible random allocation program that assigns treatments to patients according to their prognostic factors in multi-institutional clinical trials. The source lists are available in the appendix of this paper. This program is based on Pocock and Simon's minimization method and Zelen's method for institution balancing. The numbers of institutions, treatments, and prognostic factors can be set arbitrarily. The maximum number of institutions, treatments, or prognostic factors that can be accommodated by the program is limited only by the size of the main memory. For example, an IBM-PC with a 640KB main memory can run a program of 1500 institutions, 4 treatments and 20 prognostic factors.

The research trend of life sciences in Japanese universities based on literature database search

We searched literature databases regarding the four Japanese universities that published the highest number of life science papers. The databases used in this study were MEDLINE and EMBASE. As a result, there was a 30% difference in the number of papers among the four universities.

Relationship between age and the time of surgery and prognosis after gastrectomy for gastric cancer

We did a retrospective study to assess the influence of age on the prognosis in 1,537 patients with gastric cancer and who underwent gastrectomy. The patients were classified into 7 groups by age at the time of surgery, and the relative survival rates were calculated after correcting for each patient's sex, age, and the operative calendar year, based on the life table data for the general Japanese population. The overall prognoses in patients under age 30 and over age 80 years were poor (for ages under 30 years, 30-39, 40-49, 50-59, 60-69, 70-79, and over 80 years, the 5-year survival rates were 32.1%, 55.9%, 54.8%, 54.3%, 48.6%, 50.8%, and 31.5%, respectively). The poor prognoses in the youngest patients could be attributed to a high frequency of aggressive stage of the tumor. After curative gastrectomy, although the prognoses were excellent for every category in the first and second postoperative year, patients over age 80 years had a relatively poor prognosis after the third postoperative check-up. The poor prognoses in the oldest patients were attributed to the number of deaths due to other diseases. We conclude that for the very young or old subjects, age is a significant prognostic factor for those treated by gastrectomy for gastric cancer.

A comparison of the logistic regression and the Cox proportional hazard models in retrospective studies on the prognosis of patients with gastric cancer

To define the independent prognostic factors reducing survival time for gastric cancer, we compared the logistic regression and the Cox proportional hazard models applied to patients who underwent curative gastrectomy. All patients were evaluated after being followed for long fixed periods. Of 1,019, 269 (26.4%) died of tumor recurrence within a 5-year period and 36 (3.5%) died over 5 years after the original surgery. With regard to survival time, multivariate analyses using the Cox proportional hazard model in a stepwise manner adjusted for the sex, age, and 10 other factors, suggested that size of tumor (P < 0.01, relative risk [rr] = 1.0962), degree of gastric wall invasion (P < 0.01, rr < 1.3520), and status of lymph node metastasis (P < 0.01, rr = 1.6572) were the most independent prognostic factors. As well as, using the stepwise logistic regression model, size of tumor, (P < 0.01, odds ratio [or] = 1.115), degree of gastric wall invasion (P < 0.01, or = 1.428), and status of lymph node metastasis (P < 0.01, or = 2.182) were also the most independent risk factors for recurrence within 5 years after surgery. Although regression coefficients are not all the same, these three factors proved significant in both multivariate analyses. This equation for risk factors for prognosis is approached when searching for an appropriate method of retrospective studies using multivariate analyses.