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Biomedical subjects

J Kobayashi

Publications and source records attributed to J Kobayashi.

At least 613 records · Page 34Linked to original sources
PubMedDate not supplied

Hepatocellular carcinoma exhibiting a concentric structure of different histologic grades: evaluation by chondroitin sulfate iron colloid-enhanced MR imaging.

A patient with hepatocellular carcinoma exhibiting a concentric structure of different histologic grades was examined with chondroitin sulfate iron colloid (CSIC)-enhanced MR imaging. After CSIC injection, the advanced component was enhanced in comparison with the surrounding liver, and the well-differentiated component was not enhanced. CSIC-enhanced MR imaging was helpful in evaluating histologic grade on the basis of reticuloendothelial function.

Carcinoma, Hepatocellular↗
PubMedDate not supplied

Etiology of intellectual impairment in Duchenne muscular dystrophy.

The precise etiology of intellectual impairment in Duchenne muscular dystrophy (DMD) is unknown. Histopathologic and computed tomographic studies have revealed structural brain changes; however, to our knowledge, no cranial magnetic resonance imaging (MRI) studies have been performed on DMD patients to further delineate these structural changes. We prospectively studied 4 DMD patients by cranial MRI, DNA deletion analysis, clinical evaluation, and intelligence testing. There was no significant correlation between verbal intelligence scores and MRI findings, DNA deletion, or the clinical severity of the disease. These first MRI studies of DMD did not reveal any significant anatomic brain alteration, other than mild atrophy in 2 patients. We believe these results must be considered when investigating the etiology of intellectual impairment in DMD in future studies with larger patient samples.

Adolescent↗
PubMedDate not supplied

Cytotoxic macrolides from a cultured marine dinoflagellate of the genus Amphidinium.

A fourth cytotoxic macrolide, amphidinolide D[1], together with known amphidinolide B[2], has been isolated from a different batch of the cultured dinoflagellate Amphidinium sp., which was symbiotically associated with an Okinawan flatworm Amphiscolops sp. Two-dimensional nmr experiments including 1H-detected heteronuclear multiple-bond correlation (HMBC) resulted in the structure assignment of 1 and structure revision of the diene moiety (C-13-C-15) of amphidinolide B.

Animals↗
PubMedDate not supplied

Metachromin C, a new cytotoxic sesquiterpenoid from the Okinawan marine sponge Hippospongia metachromia.

A new sesquiterpenoid quinone, metachromin C[1], with potent cytotoxic activity has been isolated together with a known terpenoid metachromin A[2] from the Okinawan marine sponge Hippospongia metachromia and the structure determined by spectroscopic data, especially several types of 2D nmr spectra including 1H-detected heteronuclear multiple-bone correlation (HMBC).

Animals↗
PubMedDate not supplied

Effects of cigarette smoking on blood levels of leukotrienes and plasma levels of complements C3a and C5a in healthy volunteers.

We reported previously that cigarette smoking induces bronchoconstriction. In the present investigation we measured the level of peripheral venous blood leukotrienes, which are known to cause marked bronchoconstriction, and plasma complement C3a and C5a, which are known to have chemotactic and anaphylatoxic activities. All of these showed a significant increase after cigarette smoking. These data may suggest that the activation of complement induces the release of leukotrienes, and that these leukotrienes cause bronchoconstriction. It appears likely, therefore, that cigarette smoking induces an increase in peripheral venous blood leukotrienes and complement C3a and C5a, and that such an increase may elicit bronchoconstriction.

Adult↗
PubMedDate not supplied

Effect of lazaroid U-74389G on pulmonary ischemia-reperfusion injury in dogs.

Lipid peroxidation induced by oxygen free radicals is a contributing factor in ischemia-reperfusion injury. Lazaroid U-74389G (LAZ-G) is a group of new synthetic 21-aminosteroids and inhibits irondependent lipid peroxidation. We investigated the effects of LAZ-G on pulmonary ischemia-reperfusion injury in dogs. Twenty dogs were divided into three groups. In the LAZ-G group (n = 6), LAZ-G was administered 15 min before ischemia. In the St group (n = 5), methylprednisolone was injected 15 min before ischemia and 15 min before reperfusion. In the control group (n = 9), the vehicle of Lazaroid was injected 15 min before ischemia. Warm ischemia was induced for 3 h by clamping the pulmonary artery and veins. Arterial oxygen saturation (SaO2), cardiac output (CO), left pulmonary vascular resistance (L-PVR), and blood levels of interleukin-1beta mRNA were measured. The lung specimen was harvested for histologic study and polymorphonuclear neutrophils (PMNs) counting. SaO2 levels at 30 min and 2 h after reperfusion were significantly higher in the LAZ-G group than in the control group. After 30 min of reperfusion, CO was significantly better in the LAZ-G group than in the St and control groups, and the L-PVR level was significantly lower in the LAZ-G group than in the control group. Survival rates were significantly better in the LAZ-G group than in the control group. Histological damages and PMNs infiltration were more severe in the control group than in the LAZ-G group. Interleukin-1beta mRNA levels were lower in the LAZ-G group than in the control group. Lazaroid U-74389G appears to generate a protective effect against ischemia-reperfusion injury of the lung.

Animals↗
PubMedDate not supplied

Imaging analysis of platelet deposition on the extracardiac valved conduit in humans.

In 14 patients (aged 2-29 yr) with Hancock (n = 11) or Carpentier-Edwards extracardiac valved conduits (n = 3), platelet deposition (PD) was investigated using indium 111 (111In) platelet imaging. Repeated studies were performed in five patients. By visual analysis, 71% (5/7) of the imagings (7 images/5 patients) showed PD at early study 1-3 months after surgery, 9% (1/11) at intermediate study at 6-46 months (mean 21 mon) (11 images/10 patients) and 0% at late study at 81-132 months (3 images/3 patients). Quantitative analysis was made using relative ratio of radioactivity at the graft area to the area of the brachiocephalic artery (platelet accumulation index or PAI). The PAI was 1.85 +/- 0.47 (mean +/- SD) at early study, 1.51 +/- 0.23 at intermediate, and 1.36 +/- 0.37 at late study (NS). There was no significant difference in the late pressure gradients across the conduit (16-68 mon postoperatively) between the two groups with (n = 3) and without (n = 5) PD at the early stage (1-18 mon postoperatively, n = 8). The result may indicate that PD to the valved conduit in the right ventricular (RV) outflow tract occurs early postoperatively (mostly within 3 mon). The relationship of the PD detected by this method to late obstruction was not clarified in this study.

Adolescent↗
PubMedDate not supplied

Long-term circulatory support to promote recovery from profound heart failure.

In profound heart failure, ventricular assist systems (VAS) have been used to maintain the systemic circulation and promote recovery of the failing heart. The authors' data suggest that the heart may not recover sufficiently if the patient needs left ventricular assist beyond 10 days. Recently, the authors treated six patients who were supported by VAS more than 3 weeks and were weaned from VAS. Four of six patients were weaned from VAS and continue well, despite marginal cardiac function. In the other two patients, the natural heart did not sustain stable recovery, but their general conditions made them fit to be candidates for heart transplantation. Based on these data, long-term support should be considered to promote recovery of heart function with the use of VAS for profound heart failure.

Adolescent↗
PubMedDate not supplied

Recovery of cardiac function by long-term left ventricular support in patients with end-stage cardiomyopathy.

Effects of long-term left ventricular (LV) support on end-stage cardiomyopathy patients is unclear. We applied our LV assist system (LVAS) to six heart transplant candidates, aged 17 to 49, with dilated cardiomyopathy, including one dilated phase hypertrophied cardiomyopathy. LVAS was installed between the left atrium and the ascending aorta, and the pump was positioned parecorporeally. In all patients, their general condition improved, and their pump flows were kept at 4 to 5 L/min. Exercise was started after stabilization of their general condition under constant pump flow. Natural heart size and function were examined by echocardiography. In the beginning of assist, all patients showed impaired cardiac function and LV dilation. During LV assist, systolic function measured by ejection time improved in all patients. Left ventricular end-diastolic dimension (LVDd), showed a remarkable decrease in two patients, who were weaned from LVAS after 3 months of support. They are doing well more than 1 year and 3 years after removal; peak VO2 levels (ml/min/kg) were 30 at 1.2 years and 27 at 2.7 years after removal. In the other four patients, however, LVDd had no remarkable changes, and three could not be weaned from LVAS. The last was discontinued from LVAS after 5 months of support because of infection and died 2 months after removal. From this experience, long-term LVAS may provide the chance for recovery of the natural heart in patients with end-stage cardiomyopathy. The patients whose hearts showed remodeling were able to be weaned from LVAS, and their heart function maintained in good condition for several years.

Adolescent↗
PubMedDate not supplied

Surgery for aortic regurgitation caused by Behcet's disease: a clinical study of 11 patients.

Surgical treatment for aortic regurgitation (AR) caused by Behcet's disease is difficult due to the need to manipulate fragile, inflamed tissue. Valve detachment following aortic valve replacement (AVR) and suture detachment are serious postoperative complications. We investigated the surgical results in 11 patients. Between 1981 and July 1999, 11 patients, 9 males and 2 females, with AR caused by Behcet's disease underwent surgery. The age of these patients ranged from 33 to 60 years (mean, 45+/-8 years). The surgical procedures for AR were AVR in six patients and valved conduit operation in five patients. No patient died during the hospital stay. In a follow-up period ranging from 3 to 204 months (mean, 93+/-64 months) two patients died. Prosthetic valve detachment or suture detachment necessitating redo-operation occurred in four patients (36%) who then underwent a valved conduit procedure as a reoperation. Prosthetic valve detachment was higher in patients with AVR than in patients with a valved conduit operation. Valved conduit reconstruction is indicated in patients with AR caused by Behcet's disease in whom prevention of valve detachment is difficult even by current valve fixation methods.

Adult↗
PubMedDate not supplied

Immunomodulatory action of levofloxacin on cytokine production by human peripheral blood mononuclear cells.

Levofloxacin (LVFX), the bacteriologically active isomer of ofloxacin, is a fluorinated quinolone. LVFX suppressed the proliferative activity of peripheral blood mononuclear cells (PBMC) stimulated with phytohemagglutinin (PHA). LVFX increased interleukin-2 (IL-2) production by PBMC stimulated with PHA in a dose-dependent manner, with more than 10 micrograms/ml of LVFX causing a significant increase. The granulocyte-macrophage colony-stimulating factor and soluble IL-2 receptor production by PHA-stimulated PBMC was suppressed at high concentrations of LVFX. Interleukin-1 beta production by lipopolysaccharide-stimulated PBMC was suppressed in a concentration-dependent manner by LVFX, and tumor necrosis factor-alpha production was suppressed at only the highest concentration. In contrast, interleukin-8 production was little affected by LVFX. These results show that LVFX has an immunomodulatory action on cytokines production by PBMC independent of its antimicrobial activity.

Adjuvants, Immunologic↗
PubMedDate not supplied

Gelatin particle indirect agglutination test for serodiagnosis of schistosomiasis: comparative study with enzyme-linked immunosorbent assay.

A new serological test, the gelatin particle agglutination test (GPAT), was used for the serodiagnosis of schistosomiasis mansoni. This technique showed the sensitivity (90.6%) and specificity (97.8%) close to those of enzyme-linked immunosorbent assay. The GPAT can be easily and rapidly performed without specialized equipment, by using lyophilized antigen-coated gelatin particles. The test also seems to be useful for mass screening of Schistosoma infection in field conditions.

Agglutination Tests↗
PubMedDate not supplied

Prevalence of intestinal parasitic infection in five farms in Holambra, São Paulo, Brazil.

A parasitological survey was carried out on 222 inhabitants of five farms in Holambra, located 30 km north of Campinas, São Paulo, Brazil, on October 1992. Approximately 70% of the inhabitants were found to be infected with at least one species of intestinal parasite. The positive rates of 6 helminths and 7 protozoan species detected are as follows: 5.4% Ascaris lumbricoides; 8.6% Trichuris trichiura; 19.8% Necator americanus; 10.4% Strongyloides stercoralis; 1.4% Enterobius vermicularis; 0.9% Hymenolepis nana; 3.2% Entamoeba histolytica; 2.7% E. hartmanni; 9.9% E. coli; 14.0% Endolimax nana; 2.3% Iodamoeba butschlii; 10.4% Giardia lamblia; 37.8% Blastocystis hominis. The positive rates of helminth infection were generaly higher in the younger-group under 16 years-old than those in the elder group aged 16 or more, whereas the infection rates of protozoan species were higher in the elder group. The infection rate of Strongyloides was found to be 10.4% by a newly developed sensitive method (an agarplate culture methods).

Adolescent↗