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Percutaneous microwave coagulation therapy (PMCT) is a new technique for the treatment of hepatocellular carcinoma (HCC). However, it is difficult to distinguish those lesions in which necrosis has been induced from the viable residual lesions during the procedure, because the margin of the tumor becomes unclear during PMCT. We determined the area of necrotic lesions during the procedure using color Doppler imaging. PMCT was performed on 10 patients (17 lesions) with recurrent HCC. The electrode of the microwave delivery system was moved around the tumor and the surrounding area until color mosaic images disappeared from the entire area of the tumor. The areas in which necrotic tissue was indicated by color Doppler imaging were later confirmed by other modalities such as angiography or contrast-enhanced computed tomography. This leads us to believe that real-time, effective evaluation of PMCT is possible with color Doppler imaging.

Intrathymic (i.t.) injection of allogenic cells without administration of anti-lymphocyte serum (ALS) in neonatal recipients has induced donor-specific tolerance to subsequent cardiac allografts in rats. This study examines whether similar tactics can be successfully applied to a hamster-to-rat cardiac xenotransplantation model. Lewis neonates on their first day of life underwent i.t., subcutaneous (s.c.), intraperitoneal (i.p.), or intravenous (i.v.) injections of 5 x 10(7) Golden Syrian hamster splenocytes. After six weeks, the rats underwent heterotopic cardiac transplantation of hamster hearts. Cyclophosphamide (CyP) was administered on the day before surgery and postoperatively to suppress antibody-mediated graft rejection. Rats given splenocytes with 80 mg/kg of CyP had the following graft survival times: 8 to 12 days for i.t. injection (mean, 9.4 days); 5 to 7 days for s.c. injection (mean, 6.6 days); 4 to 11 days for i.p. injection (mean, 7.4 days); and 4 to 13 days for i.v. injection (mean, 7.9 days). Only the extension of graft survival produced by i.t. injection was statistically significant in comparison with the rats given only CyP treatment (mean, 7.5 days; P < 0.05). Thus, it appears that i.t. injection of xenogenic splenocytes in neonatal recipients with administration of CyP, but without ALS, can prolong xenograft survival. This biological intervention may be most useful in pediatric xenotransplantation when combined with other immunomodulation techniques.

In order to elucidate factors influencing the prognosis of small-cell lung cancer (SCLC), we reviewed the records of 253 patients with SCLC and evaluated 20 pretreatment prognostic factors by univariate analysis and Cox's multiple regression analysis. Recursive partitioning and amalgamation (RPA) was employed to identify subgroups with similar survival rates. Cox's multiple regression analysis identified five significant factors: extent of disease, number of metastatic sites, serum albumin, serum lactate dehydrogenase, and presence of weight loss. Among these, extent of disease was the most influential factor. RPA analysis revealed three subgroups predicting significantly different prognoses. The median survival time and 3-year survival rate were 18.4 months and 20.6%, respectively for the good-risk group (limited disease without weight loss), 13.5 months and 9.1%, respectively for the intermediate-risk group (limited disease with weight loss or extensive disease with less than two metastatic sites), and 9.2 months and 0%, respectively for the poor-risk group (extensive disease with two or more metastatic sites). These results will be useful for development of new staging system or subsequent stratification for randomized trials.

Recent data suggested that platelet-activating factor (PAF) could play a pathophysiologically important role in the progression of hypoxic-ischemic brain injury. We investigated brain tissue PAF concentration in the hypoxic-ischemic brain of immature rats. Endogenous PAF concentration in brain tissue showed a marked increase in hypoxic-ischemic pups (Group 1, 85.6 +/- 15.5 pg/mg protein) when compared to that of the control (9.1 +/- 3.1 pg/mg protein). In addition, we studied the effects of pretreatment with L-carnitine (5 days and 2 h before the hypoxia) on endogenous PAF concentration in the hypoxic-ischemic brain. Endogenous PAF concentration in the short-term pretreatment group (Group 2, 81.6 +/- 9.7 pg/mg protein) was not different than in Group 1 rat pups. However, a significantly decreased PAF concentration was found in the group of pups that received carnitine pretreatment for 5 days (Group 3, 30.5 +/- 11.0 pg/mg protein). These results indicate that PAF is an important mediator in the immature rat model of cerebral hypoxic-ischemic injury. The suppressor effect of L-carnitine on PAF production may give new insight into the treatment of hypoxic-ischemic brain injury.

A method of intracranial transplantation of the tumor induced by adenovirus type 12 in syrian hamster has been described. The incidence of intracranial tumor development was 86 (90.5 %) out of 95 animals and the average survival time and tumor size at death were 15.1 days and 4.1 mm in diameter respectively. The consistency of the days of death after intracranial transplantation of the tumor was remarkable. The transplanted tumors developed preferentially at the site of implantation and tumor cell seeding and tumor growing took place rarely along the ventricular system. Glial or lymphoid cell response to the tumor was not observed at any stage after transplantation in surrounding cerebral tissues of the animals. Histomorphologically, no elementary differences were observed between intracranially transplanted tumors and serially transplanted subcutaneous tumors. These facts permit the system to be applied to an experimental brain tumor model as large-scale testing.

A carboxyfluorescein (CF)-enveloping soybean phosphatidylcholine liposome was used as a model of physicochemical damage of biomembranes. The liposomes were exposed to a metal-chelate complex [2 mM of ferric nitrilotriacetate (FeNTA) or cupric nitrilotriacetate (CuNTA)] plus a reductant (2 mM of ascorbate or various concentrations of reduced glutathione), and CF release from damaged liposomal membranes and the generation of thiobarbituric acid-reactive substances (TBARS) were measured. In the presence of a reducing agent, both FeNTA and CuNTA stimulated markedly CF release and an increase in the TBARS level, while in the absence of a reducing agent both of the chelate complexes showed little CF release and TBARS. The effects of H2O2 addition to the reaction system containing liposome with FeNTA or CuNTA plus ascorbate were also examined. The CF release was slightly increased by the addition of a smaller dose (0.5 mM) of H2O2 and it was inhibited by 8 mM of H2O2. A similar result was obtained in the TBARS test. These results suggest that FeNTA- or CuNTA-mediated lipid peroxidation can damage liposomal membranes physicochemically, and the redox reaction of the chelated metal itself is more important than a Fenton-type reaction in the process.

Stress is a proximal interphalangeal (PIP) joint model was analyzed by the two-dimensional and three-dimensional finite element methods (FEM) to study the onset mechanisms of the middle phalangeal base fracture. The structural shapes were obtained from sagittally sectioned specimens of the PIP joint for making FEM models. In those models, four different material properties were given corresponding to cortical bone, subchondral bone, cancellous bone and cartilage. Loading conditions were determined by estimating the amount and position of axial pressure added to the middle phalanx. A general finite element program (MARC) was used for computer simulation analysis. The results of the fracture experiments compared with the clinical manifestation of the fractures justify the applicability of the computer simulation models using FEM analysis. The stress distribution changed as the angle of the PIP joint changed. Concentrated stress was found on the volar side of the middle phalangeal base in the hyperextension position, and was found on the dorsal side in the flexion position. In the neutral position, the stress was found on both sides. Axial stress on the middle phalanx causes three different types of fractures (volar, dorsal and both) depending upon the angle of the PIP joint. These results demonstrate that the type of PIP joint fracture dislocation depends on the angle of the joint at the time of injury. The finite element method is one of the most useful methods for analyzing the onset mechanism of fractures.

Using in vivo and in vitro experimental models, the uptake and excretion of 67Ga-citrate in tumor cells and normal cells were studied. The time-lapse accumulation of 67Ga in the tumor of rats bearing Yoshida sarcoma reached its peak 24 h after the administration of 67Ga and gradually decreased thereafter. However, the excretion of 67Ga from the tumor was less than that from normal lung. For culture cells in vitro, the uptake of 67Ga increased with lapse of contact time between 67Ga and the cells, but there was no distinct difference between the results of tumor cells and normal skin fibroblasts. The excretion of 67Ga from the cells tended to decrease with prolongation of the contact time, the excretion from tumor cell being only about 10% after a contact time of 24 h. This indicated a significant delay in excretion in comparison with that of normal skin fibroblasts. This delay in the excretion of 67Ga may be an important factor in the tumor accumulation of 67Ga.

The development of useful therapy for intraabdominal carcinomatosis originating from gastrointestinal cancer is an important theme in cancer therapy. We developed recently an experimental model of intraabdominal carcinomatosis in nude mice by intraperitoneal transplantation of human colon cancer cells (RPMI 4788). Using this model, we investigated the antitumor effects of recombinant human interferon (rIFN)-beta and rIFN-gamma administered singly or in combination. Treatment was initiated 2 days after CD-1 nude mice were inoculated intraperitoneally with 5 X 10(6) RPMI 4788 cells. Intraperitoneal administration for 10 consecutive days of either rIFN-beta (2.5 X 10(5) IU/mouse/day) or rIFN-gamma (2.5 X 10(5) JRU/mouse/day) resulted in a significant prolongation of survival compared with the saline control group [survival in the control: 41.8 +/- 5.6 days (mean +/- SD)]. Combined administration of rIFN-beta and rIFN-gamma for 10 days yielded a marked synergistic effect on the prolongation of survival (114.0 +/- 8.2 days). However, combined administration of rIFN-beta and rIFN-gamma in a single dose equal to the total dose given fractionally over 10 days did not yield a synergistic effect. These results suggest that daily administration of rIFN-beta and rIFN-gamma combined may provide a highly potent antitumor effect against human peritoneal carcinomatosis.

Since clinical document architecture (CDA) became an American National Standards Institute (ANSI)-approved health level seven (HL7) Standard, many countries have begun making an eff ort to make local standards conform to CDA. In order to make CDA compatible with the many diff erent local standards existing in diff erent countries, we designed a prototype model using HL7 CDA R2 with medical markup language (MML), a Japanese medical data exchange standard. Furthermore, a referral letter system based on this model was developed. Archetypes were used to express medical concepts in a formal manner and to make 2 diff erent standards work collaboratively. We share herein the experience gathered in designing and implementing a referral letter system based on HL7 CDA, Release 2 (CDA R2). We also outline the challenges encountered in our project and the opportunities to widen the scope of this approach to other clinical documents.

We discuss the concept of social capital, which has received much attention recently. Social capital is important for the following 2 key reasons:(1) a highly democratic polity and a strong economic performance that attaches great importance to the public good can be achieved on the basis of high social capital;and (2) social capital can effect health status in the human population, and widening of income inequality harms human health through the erosion of social capital. In addition, there are 3 political implications of social capital for Japanese society:(1) social capital has implications for the political decision of whether Japanese society should adopt a “medium burden for medium welfare” or a “low burden for small welfare” model together with the concept of social overhead capital;(2) reciprocity, which is one of the primary components of social capital, is similar to the philosophy underlying the health care system of Japan;(3) Japanese society needs to change from a society that emphasizes the relationships between its members to a society that is open to outsiders and has sufficient opportunities.

In the present study, we examined the dynamic of school-health-based parasite control and the related socio-economic influences. This is an ecological study based on data from 46 prefectures in Japan. The exponential decay of Ascaris lumbricoides prevalence was calculated by iterative least-squares method. Pearsonʼs correlation and multiple linear regression model analysis were performed to assess the associations between the prevalence of Ascaris lumbricoides in Japanese school children and socio-economic variables such as the prefecture income per capita, the percentage of primary industry, the population density per 1 km2, the diffusion rate of population under water supply, and the percentage of upper secondary school enrollment. The results indicated that the parasite carrier rate was higher in younger students. The half-life of Ascaris lumbricoides prevalence was approximately 3 years with significant variation among prefectures. Multiple regression analyses showed that the decrease of infection in elementary and lower secondary school children had a significant positive association with primary industry and a significant negative association with prefecture income per capita. The school-health-based parasite intervention differs by prefecture and has changed over time according to the respective prefectural stage of economic development.

The aim of this study is to clarify visual symptoms and compliance with spectacle wear in children kusing progressive addition lenses (PALs). Ninety-two children, participating in a randomized, doublemasked, crossover trial to determine whether PALs reduce myopia progression (mean+/-SD age: 11.0+/-1.6 years; refractive errors: 3.11+/-1.34 D), wore PALs (1.50 D near addition) or single vision lenses (SVLs) for 18 months, alternately. A questionnaire survey was performed 6 and 12 months after the beginning of the use of the lenses (6-month survey), and the results were compared between PAL- and SVL-wearing periods. In the PAL-wearing period, the children reported difficulty in adapting to newly provided spectacles (36%), disturbances in distance vision (22%), vertigo in the lateral gaze (11%), and difficulty in ascending and descending stairs (9%). However, the frequency of these symptoms was not significantly different from that reported in the SVL-wearing period. There was no difference in compliance with spectacle wear between the PAL- and SVL-wearing periods, and 98% of the children wearing PALs reported excellent compliance. The results of this study indicate that, compared with SVLs, the PALs provide a similar level of comfort and compliance with spectacle wear for myopic children.

Our study aimed to investigate the potential radioprotective effects of N-acetylcysteine (NAC) by comparing its biochemical effects with those of WR-2721, as a representative of clinically used radioprotectors, in preventing oxidative damage caused by gamma irradiation (single dose, 6Gy) in normal rat tissue. The rats (n=40) were divided randomly and equally into 4 groups:Control (C), Radiation (R), R+NAC (received irradiation and 1,000mg/kg NAC) and R＋WR-2721 (received irradiation and 200mg/kg WR-2721) rats. Liver tissues and blood samples were harvested and utilized for reduced glutathione (GSH), malondialdehyde (MDA) and myeloperoxidase (MPO) detection. Serum and tissue GSH levels of R rats decreased compared to those of other groups (p<0.01). Tissue MDA levels of R+NAC and R+WR-2721 rats decreased compared to R rats (p<0.01;p<0.05, respectively). Tissue MPO activities of R+NAC and R+WR-2721 rats were higher than those of R rats (p<0.001). Serum MPO levels of R+WR-2721 rats were lower than those of C rats and R rats (p<0.01, p<0.001, respectively). In conclusion, the study suggests that the radioprotective effect against radiation-induced oxidative damage of NAC may be similar to that of WR-2721.

We examined whether selected circulatory diseases (heart disease, stroke, diabetes and hypertension) were associated with an increased risk of major depression in the Japanese community population. Face-to-face household surveys were carried out in 7 areas, and a total of 2,436 persons participated (overall response rate: 58.4%) from 2002 to 2004. The WHO Composite International Diagnostic Interview 3.0 was used to diagnose major depression according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and additional interviews assessed the presence of circulatory diseases. Using data from a random subsample of the respondents (n=832), we conducted Cox proportional hazards models to calculate hazard ratios for the onset of major depression with comorbid circulatory diseases as a time-dependent covariate. Heart attack was significantly associated with the onset of major depression (hazard ratio [HR], 7.51 [95%Confidential Interval (CI), 1.36-41.45]) after adjusting for sex, birth cohort, smoking, alcohol intake, and education. Heart disease (HR, 2.12 [95% CI, 0.79-5.70]), diabetes (HR, 2.36 [95% CI, 0.42-13.34]) and hypertension (HR, 0.97 [95% CI, 0.37, 2.50]) were not significantly associated. There were no subjects who developed major depression after stroke. These results suggest that heart attack, and maybe also heart disease and diabetes, affect the onset of major depression.

We studied the in vivo antitumor effects of natural human tumor necrosis factor-alpha (nHuTNF-alpha) and natural human interferon-alpha (nHuIFN-alpha), both of which were produced by HVJ (hemagglutinating virus of Japan)-stimulated acute lymphatic B cell leukemia line, BALL-1 cells. To clarify the interaction between nHuTNF-alpha and nHuIFN-alpha, we used novel experimental models of lung metastasis and intraabdominal carcinomatosis which we developed in nude mice using a human tumor line, RPMI 4788. While the intravenous administration of nHuTNF-alpha or nHuIFN-alpha alone inhibited lung metastasis, the two cytokines given in combination synergistically inhibited lung metastasis. In a comparative study, nHuTNF-alpha and recombinant human interferon-gamma (rHuIFN-gamma) in combination also synergistically inhibited lung metastasis. Treatment with nHuTNF-alpha and nHuIFN-alpha combined significantly prolonged the survival of nude mice with intraabdominal carcinomatosis. Complete regression of five different human tumor xenografts was achieved by the simultaneous intratumoral injection of nHuTNF-alpha and nHuIFN-alpha. Histological examination revealed that tumor cell lysis occurred 24 h after the intratumoral administration of the cytokines. No significant signs of toxicity to nude mice were observed at any dose tested. The synergism of nHuTNF-alpha and nHuIFN-alpha may allow treatment at a relatively low dose range, thus minimizing side effects. The wide range of anticancer activity of these agents may provide better therapeutic efficacy. The in vivo assay systems which we have developed are useful for the analysis of the biological activities and interactions of cytokines and chemotherapeutic drugs.

The surface of Gross virus-induced murine lymphoblasts and C-type virus particles budding from these cells were investigated under the scanning electron microscope (SEM). The cells appeared spindle-shaped or roughly-rounded with extensive surface features consisting of microvilli, blebs and ruffled membranes. C-type virus particles were detected on the cell membrane as small spherical particles, distinguishable from the microvilli. Clustered virions were observed in some cases. However, the distribution of virions appeared to be random. The surface of the virion was smooth and had no globular units at high magnification. These morphological observations were confirmed in ultrathin sections.

Malignant lymphoma was induced in Japanese (JWY), New Zealand (NZY) and Dutch (DUY) white rabbits by oral spray of cell-free pellets of culture fluid (crude virus fraction) of Ts-B6 cells (cynomolgus monkey B-lymphoblastoid cells harboring Epstein Barr virus-related simian herpesvirus or Cyno-EBV). Nine of 11 inoculated rabbits developed malignant lymphomas within 42-160 days after oral inoculation (JWY, 2/3; NZY, 5/6; DUY, 2/2). In contrast, none of the control rabbits inoculated in the same fashion with B95-8 (EBV-producing marmoset cell line) cell-free pellets developed malignant lymphoma. Most rabbits showed increased anti-VCA IgG and anti-EA-DR IgG antibody titers after inoculation by oral spray of Ts-B6 cell-free pellets. EBV-encoded RNA-1 was revealed in the tumor cells by in situ hybridization. EBV DNA was detected in the rabbit peripheral blood leukocytes (PBL) by polymerase chain reaction; the earliest positive result was obtained only two days after oral inoculation. These data suggest that orally administered Cyno-EBV in Ts-B6 cells infects PBL and then induces malignant lymphoma in rabbits. The availability of this animal model promises to clarify the role of EBV in human lymphoma and provides a means for studying prophylactic and therapeutic regimens.

A number of approaches have been put forward to monitor spinal cord ischemia during thoracic and thoracoabdominal aortic occlusion. However, none of these can ultimately prevent devastating complications which result from ischemic spinal cord injury. A direct measurement of the oxygen content of the spinal cord may accurately indicate the perfusion state, but in practice it is impractical. We surmised that intrathecal and/ or epidural oxygen concentration(I-pO₂ and E-pO₂, respectively) accurately reflect oxygen content in the spinal cord. So, we examined whether or not I-pO₂ and/or E-pO₂ correlated with the spinal cord pO₂ (S-pO₂) in dogs. In nine mongrel dogs, a model of graded spinal cord ischemia was developed by stepwise alternation of the level of aortic occlusion with an intraaortic balloon catheter. I-pO₂, E-pO₂ and S-pO₂ were measured with a mass spectrometer. Our results show that, both I-pO₂ and E-pO₂ significantly correlated with S-pO₂. I-pO₂ correlated with S-pO₂ better than E-pO₂ did. Therefore, I-pO₂ can be used as a new indicator for spinal cord ischemia, and I-pO₂ monitoring would be useful to prevent paraplegia associated with thoracic aortic surgery.

Previous EEG studies have shown that transcendental meditation (TM) increases frontal and central alpha activity. The present study was aimed at identifying the source of this alpha activity using magnetoencephalography (MEG) and electroencephalography (EEG) simultaneously on eight TM practitioners before, during, and after TM. The magnetic field potentials corresponding to TM-induced alpha activities on EEG recordings were extracted, and we attempted to localize the dipole sources using the multiple signal classification (MUSIC) algorithm, equivalent current dipole source analysis, and the multiple spatio-temporal dipole model. Since the dipoles were mapped to both the medial prefrontal cortex (mPFC) and anterior cingulate cortex (ACC), it is suggested that the mPFC and ACC play an important role in brain activity induced by TM.