Biomedical subjects

S Kato

Publications and source records attributed to S Kato.

At least 1,225 records · Page 68Linked to original sources

PubMed1990

Isolation and characterization of cell clones persistently producing teardrop-shaped particles of human immunodeficiency virus type 1.

Several cell clones producing teardrop-shaped human immunodeficiency virus type 1 (HIV-1) particles were isolated from MT-4 cells that survived HIV-1 infection after extensive cell lysis. Most of the teardrop-shaped particles contained an electron-dense core structure, and the particles could replicate in MT-4 cells. No significant structural difference in the HIV-1 proteins was observed between these cell clones and the MOLT-4 cells producing intact HIV-1 particles, although their envelope structure is morphologically abnormal.

Acetylglucosaminidase↗

PubMed1990

[Epidemiological and therapeutic study on gonorrheal infection--study on NY-198 (lomefloxacin) single administration therapy. Sapporo Clinical Research Group for STD].

The efficacy of single administration of NY-198 in the treatment of gonococcal infections was studied employing male patients with gonorrheal urethritis and female patients with gonorrheal cervicitis. The clinical efficacy was evaluated on the basis of the efficacy rates which was estimated on each observation day for each patient. In the male patients, NY-198 was administered in a dose of 200 mg in 25 cases and a dose of 400 mg in 65 cases. The rate of eradication of N. gonorrhoeae (i.e. efficacy) on the 3rd day of administration was 96% in the 200 mg administration group and 100% in the 400 mg administration group. On the 7th day after administration, the eradication rate was 100% in both the 200 mg and 400 mg administration groups. When the eradication rate on the 7th day was statistically estimated for patients who returned to the hospital only on the 3rd day, it was 97.9% in the 200 mg administration group. In the female patients, NY-198 was administered in a dose of 200 mg to 4 cases and a dose of 400 mg to 5 cases. The eradication rate on each observation day was 100% in both dosage groups. In conclusion, single administration of NY-198 in a dose of 200 mg or 400 mg was highly effective, and considered to be a therapeutic method highly useful clinically.

4-Quinolones↗

PubMed1990

[Personal monitoring method for volatile chloroorganic compounds].

A method for measurement of volatile chloroorganic compounds (VCOCs) in air by using porous polymer resin beads, Porapak N was developed as follows: 1. Air was sampled in a glass collection tube packed with Porapak N (1.2 g) at flow rate of 30 ml/min for 24 hours at room temperature. 2. The collection tube was set in a desorption device. The VCOCs adsorbed on the Porapak N were desorbed by heating in a nitrogen flow (180 degrees C, 50 ml/min) and trapped in 10 ml n-hexane cooled by ice. Sufficient recoveries were obtained at desorption time of 8 min. 3. The VCOCs were determined by a gas chromatograph with an electron capture detector (GC-ECD). The present method was applied to determine personal exposure levels for VCOCs. Personal exposure levels of 1,1,1-trichloroethane, carbon tetrachloride, trichloroethylene and tetrachloroethylene were 1.1-6.9, 0.1-0.9, N.D-0.4 and N.D.-4.2 ppb, respectively.

Air↗

PubMed1990

Morphological changes in human and animal enamel rods with heating--especially limits in temperature allowing discrimination between human and animal teeth.

Little has been revealed about making discrimination between human and animal using a piece of tooth found in a burned cadaver. From the viewpoint of forensic dental medicine, it is a theme no less valuable. This experimental study was attempted for this reason. Teeth from an individual body of human, monkey, dog, rabbit and rat were heated in turn on the muffle furnace. The heating temperatures were from 200 degrees C to 1,000 degrees C in time spans of 5, 30 and 60 minutes. After heating, each tooth and its control were observed by a scanning electron microscope (magnifying power: 3,500 x or 3,600 x). At heating temperature of 500 degrees C or 600 degrees C, enamel starts to come off in lumps and cracks appear in the enamel rods. The arcaded form in human and monkey, hexagon in dog, elongated chain in rabbit, rows of short, diagonal parallel lines equally directed at every other row in rat--these basic morphological features of the enamel rods--are retained till the heat reaches 700 degrees C. The enamel rods in monkey yield to heat more easily than those in human. At 600 degrees C many cracks appear and deformation of the arcaded form starts. With heating of 5 minutes at 800 degrees C the outline of the pattern is obscured. Human and animal teeth get varied forms of cracks in the enamel rods with heating more than 5 minutes at 800 degrees C. The structure of the enamel rods is broken and morphological characteristics are lost. This makes discrimination of human and animal quite difficult.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1990

[Clinico-pathological studies on the effects of pulp protection (lining) under the condition with and without smear layers].

Many studies have been made of pulpal reactions to pulp protection (lining) materials have always employed a smear layer between the dentin wall and the lining materials. In this study, the author has attempted to evaluate pulpal response without a smear layer and compared effects of pulp protection (lining) with and without smear layers. Materials and methods. The experiment employed 84 vital human teeth ranging in age from 14 to 54 years. The experimental teeth were divided into 4 groups for the purposes of histopathological studies and scanning electron microscope (SEM) observation. Group C: No EDTA-treatment and lining with gutta-percha temporary material, 10 cases for histopathological study and 4 cases for SEM observation. Group TC: EDTA-treatment and lining with gutta-percha temporary material, 10 cases for histopathological study and 4 cases for SEM observation. Group P: No EDTA-treatment and lining with Protect Cement. 20 cases for histopathological study and 8 cases for SEM observation. Group TP: EDTA-treatment and lining with Protect Cement. 20 cases for histopathological study and 8 cases for SEM observation. After local anesthesia, Black's simple class I cavities were made in the experimental teeth with a diamond instrument mounted on a high-speed air turbine at room temperature with a water spray coolant. In Groups TC and TP only, an aqueous solution of 0.5% EDTA (pH 7.4) 10 ml was applied from cavity floor to dentin for 60 seconds. All cavities were then washed with distilled water, and the dentin was dried with an air stream. The floor of cavities were lined with thin layers of the following materials: Group C and TC, gutta-percha temporary material (G-C Dental Industrial Co., Tokyo, Japan). Group P and TP lining of Protect Cement which is a zinc phosphate cement containing 0.5% paraformaldehyde (Neo Dental Chemical Products, Tokyo, Japan). The restoration of each cavity was then filled with silver amalgam. Experimental teeth were clinically observed for 2 periods: short (about 14 days) and long (about 60 days) after treatment. They were then extracted under local anesthesia and prepared for histopathological study and SEM observation. Results 1. Clinical observations. During the observation period, symptoms occurred as indicated below. Group C: 2 (20%) out of 10 cases Group TC: 3 (30%) out of 10 cases Group P: None out of 20 cases Group TP: 3 (15%) out of 20 cases The only kind of clinical discomfort observed hypersensitivity to cold water. 2. Clinical evaluations Group C: 10 cases (100%) were good.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

PubMed1990

[Histopathological studies of periodontal tissue reactions following apical plugging with autogenous dentin chips].

After treating the infected canals, we investigated to determine the influence of autogenous dentin chips accidentally applied as filling in the root apexes. Materials were 15 mandibular premolars and molars obtained from healthy, mature dogs. According to standard procedures, after pulp extirpation, canals were temporarily filled with sandarac cotton pellets and left otherwise untreated for 4 weeks. At this time, the degree of infection was ascertained. After root-canal enlargement, root canals were filled with No. 55 gutta-percha points; and a sealer (Neotriozinc Paste, AH26, or Sealapex) was applied. The animals were sacrificed at the conclusion of either a short term (2 weeks) or a long term (16 weeks), and histological studies were performed. Conclusions In short-term specimens, no formation of new hard tissue was observed at the apical dentino-cemental junction; and inflammatory changes in the periapical soft tissue were remarkable. In long-term specimens, hard-tissue formation had resulted in apical closure in 6 out of 8 instances; and periapical inflammatory changes had decreased. Relations between dentin-chip density and histopathological conditions were as follows: In most of the specimens that were evaluated as good, dentin chips were very densely applied. Insufficient numbers of dentin chips produced poor results. In other words, dense applications of dentin chips result in good prognoses. Consequently, when root-canal enlargement has been adequately performed, application of dentin chips to the apex of infected canals stimulates hard-tissue formation resulting in biological apical closure. In infected canals, however, the degree to which dentin chips are infected can be a major factor.

Animals↗

PubMed1990

Effect of intravenous injection of acetate on the pancreas of sheep.

The effect of an intravenous injection of acetate on plasma insulin and glucagon concentration was examined in conscious sheep. Sodium acetate (312 to 5000 mumol kg-1 bodyweight) injection increased plasma insulin concentrations in a dose-dependent manner. Plasma glucagon concentration was not affected by doses up to 1250 mumol kg-1. Doses of 2500 and 5000 mumol kg-1 produced significant increases (P less than 0.05), but not in a dose related manner. The results of this study indicate that the receptive mechanism of the A cell in the sheep pancreas to acetate might be different from that of the B cell.

Acetates↗

PubMed1990

Medication-induced esophagitis in children.

Clinical and endoscopic features of two pediatric cases of esophageal ulcers caused by capsules of oxytetracycline and doxycycline are described. Several cases of medication-induced esophageal injury in children have been reported until now, all of which were in association with tablets or capsules. Antibiotics are known to be responsible for medication-induced esophagitis in adults. In this study, 4 cases were caused by emepronium bromide and 3 cases, including the present patients, by antibiotics. All cases but one complained of chest pain and/or dysphagia. Although the interval between the onset of the symptoms and the diagnosis varied among cases, the clinical courses were relatively uneventful, without any long-term sequelae. This clinical entity seems to be unfamiliar to pediatricians and is omitted from the differential diagnosis.

Child↗

PubMed1990

Interferon-alpha treatment leads to accumulation of virus particles on the surface of cells persistently infected with the human immunodeficiency virus type 1.

The effect of interferon-alpha (IFN-alpha) on virus replication in cells acutely infected with human immunodeficiency virus type 1 (HIV-1) and virus production from cells persistently infected with HIV-1 was studied. In both cell systems, significant suppression was observed. However, this suppression was not due to protein synthesis of the major viral proteins. Electron microscopy revealed the accumulation of intact virus particles on the cell surface of the cells treated with IFN-alpha. Thus, IFN-alpha might suppress the release stage of the particle from infected cells.

Cell Line↗

PubMed1990

[Cardiotoxicity study of ME2303 with the interval intravenous injections to rats].

Cardiotoxic effects of ME2303 were studied upon interval intravenous administrations to rats in comparison with those of doxorubicin (ADR). ME2303 at two dose levels of 3 and 9 mg/kg/day or ADR at a dose levels of 3 mg/kg/day was injected once a week for 3 weeks to female Sprague-Dawley rats (SPF) of 5-weeks of age. ADR depressed body weight gain, decreased food intake and increased water intake. Microscopic observation on the myocardial tissues revealed that ADR caused necrosis and cell infiltration, edema and disarrangement of myofibrils in some of ADR-treated rats. On the other hand, ME2303 showed no significant effects except that some decrease of food intake was observed at a dose level 9 mg/kg/day. No changes in left ventricular functions were observed in perfused hearts isolated from ADR- or ME2303-treated rats. However, about 133 ng/g of ADR remained in the hearts even at 1 week after the final administration whereas ME2303 or its metabolites were not detected, suggesting that ADR may cause disturbance of ventricular function and more cardiomyopathy after a longer term than 1 week following the final administration. These results suggest that the cardiotoxicity of ME2303 is weaker than that of ADR in rats.

Animals↗

PubMed1990

[Three-dimensional culture of plucked human hair follicles inside the collagen gel matrix].

Plucked human hair follicles were cultured in collagen gel matrix. Epithelial cells, possibly outer root sheath keratinocytes, appeared from the outer root sheath 4 to 5 days after culturing and continually grew into the gel to form spike-like structures for next 3 weeks. The number and size of the spikes differed in each follicle. Autoradiographically, many DNA-synthesizing cells were seen at the outer cell layer in the enlarged outer root sheath and at the edges in the newly formed spike-like structures. The culture method described here appears to be suitable to study the three-dimensional growth, morphogenesis and differentiation of the outer root sheath cells in vitro.

Adult↗

PubMed1990

[Preoperative oral antimicrobial bowel preparations in elective colorectal surgery].

Colorectal surgery is associated with high incidence of postoperative wound infection due to contamination of the field of operation by organisms from the intestine. A consecutive series of 300 patients undergoing elective operations on the colon and rectum, was studied to determine the efficacy of oral antibacterial preparations on the influence of intestinal organisms at operation and the incidence of postoperative wound infection. The patients were divided into four groups as their preoperative bowel preparations as follows; 1st group: mechanical preparation alone, 2nd group: mechanical preparation and oral kanamycin, 3rd group: mechanical preparation and oral kanamycin and metronidazole, and 4th group: mechanical preparation and oral polymyxin B and metronidazole. The results of bacteriological studies on specimens taken by swab from colonic lumen and wound at operation showed effectiveness of kanamycin and polymyxin B against aerobic gram-negative rods and metronidazole against anaerobes. The rates of postoperative wound infection were 47.5% in 1st group, 27% in 2nd group, 12% 3rd group, and 2.7% in 4th group, respectively.

Administration, Oral↗

PubMed1990

Effect of feeding on plasma secretin concentrations in sheep.

Changes in plasma secretin concentration during the 24 hours after feeding were observed in five female sheep fed 1500 g of lucerne pellets and 300 g of orchard grass hay once daily. The pre-feeding concentration of plasma secretin was 50 +/- 9 pg ml-1. The plasma secretin concentration began to increase immediately after the beginning of feeding, reached values approximately double the pre-feeding values six hours after feeding, and remained significantly above the pre-feeding value for more than 10 hours after feeding (P less than 0.01 or less than 0.05).

Animal Feed↗

PubMed1990

[Intracranial multiple granuloma preceded by rheumatic disease--a case report].

In 1980, a 38-year-old man had remittent fever, swelling and arthralgia of the knee, ankle and wrist joints, as well as visual disturbance due to bilateral iritis. On his admission to our hospital, his laboratory data showed neutrophilia, normocytic normochromic anemia, hepatomegaly, hepatocellular damage, and a strongly positive RA test. All the microbiological examinations were negative. Thirty mg of prednisolone improved his symptoms and abnormal laboratory findings. Due to persistent mild arthralgia, he had continued to take 5-10 mg of prednisolone and analgesics until 1985 when he was readmitted to our hospital. In 1983, he began to complain of a steady pain around his left eye, and he sometimes had double vision. In 1985, he began to complain of decreasing left visual acuity and sensory disturbance in his left face in addition to pain in and around the eye. On his 2nd admission to our hospital, the neurological examination revealed involvement of the 2nd and 3rd cranial nerves and the 1st branch of the 5th cranial nerves of the left side. Laboratory data showed a positive RA test with RAHA titer at 1:320 and IgM at 216 mg/dl, but he had no joint deformities. The computed tomography (CT) of the brain demonstrated a high density mass of his left cavernous sinus extending to the left orbital apex. The prescription of the high dose of prednisolone (100 mg/day) relieved ophthalmic pain and improved visual acuity and neurological involvement within a week. Prednisolone was then gradually decreased to 10 mg. In 1986, he had partial and complex partial seizures.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1990

[A case of aneurysm of the inferior left ventricular wall].

Aneurysms of the inferior left ventricular wall represent only a small fraction of all aneurysms that have been reported in surgical series. And in comparison to anterior left ventricular aneurysms, a comparatively higher percentage of reported inferior wall aneurysms was classified as false. A 73-year-old male was admitted for acute inferior myocardial infarction. Three weeks after admission, cardiac catheterization was carried out. Coronary arteriography revealed triple vessel disease and left ventriculography showed an aneurysm of the inferior left ventricular wall, whose feature near the mitral annulus was multiple fenestrations. Left ventricular aneurysmectomy and aortocoronary bypass grafting to the left anterior descending artery were simultaneously performed under cardiopulmonary bypass with moderate hypothermia. The pathological feature was a true aneurysm. The postoperative course was uneventful.

Aged↗

PubMed1990

[The standard level of IgE RIST and eosinophil counts in 0-year old allergic children according to multiple factor analysis type II].

We specified three standard levels of IgE RIST (10, 20, 60 IU/ml) for the ninety-four (94) allergic clients of 0-year infants, who classified with three groups. Each group was furthermore divided in two groups such as a group under the standard level and a group exceeding the level respectively. Next, using the Multiple Factor Analysis Type II, we examined quantitative analysis that each of three classified groups was influenced on 12 allergic factors of sex, existence and inexistence of wheezing and atopic dermatitis, family history of allergic diseases, eosinophil counts. IgE RAST scores and antibody titers against egg white, milk and soybean, IgE RAST scores to Dermatophagoides farinae, while the we discussed how the standard levels were adequately reacted to the analysis. As a results, strong allergic factors which influenced the three groups commonly were two factors of IgE RAST scores to egg white and D.f. In particular, the factor which influenced the group of 10 IU/ml standard level was eosinophil counts and family history of allergic diseases. Furthermore, the strong factors which influenced the group classified on 60 IU/ml standard outstandingly appeared in IgE RAST scores to soybean, however, we did not find any difference between three groups. On the other hand, when we specified the standard level at 100/mm3, 200/mm3, 400/mm3 in regard to the eosinophil counts under the same method and examined results, we found strong allergic factors which influenced family history of allergic diseases. IgE RAST scores to egg white and soybean. However, the study scarcely recognize any difference between the three groups.

Eosinophils↗

PubMed1990

[Epinephrine decreases plasma potassium].

The effects of epinephrine infusion on plasma potassium were examined in rats. Potassium infusion (1 mEq.kg-1.h-1 over 2 hours) elevated plasma potassium 4.23 mEq.l-1. Insulin (0.064 U.kg-1.h-1) combined with glucose (0.32 g.kg-1.h-1) or epinephrine (0.05, 0.1, 0.5, 1, or 5 micrograms.kg-1.min-1) added to potassium infusion significantly depressed the increments of plasma potassium levels. Epinephrine infusions (0.05 or 0.1 microgram.kg-1.min-1) were more effective than insulin infusion combined with glucose. These results suggest that epinephrine infusion may be useful for the control of hyperkalemia.

Animals↗

PubMed1990

[The study of 201Tl, 123I-IMP-SPECT before and after radiation therapy of brain tumor].

201Tl, 123I-IMP-SPECT were performed in 17 patients with brain tumors before and after radiation therapy, compared with X-CT. 15 of 17 patients showed enhanced areas on X-CT and higher accumulations on 201Tl-SPECT in the same lesions before radiation therapy. There was significant correlation between enhanced lesions on X-CT and lesions of higher accumulation on 201Tl-SPECT before and after radiation therapy. But, the patients with residual enhanced lesions on X-CT did not always show higher accumulation on 201Tl-SPECT after radiation therapy. And, 2 patients with radiation injury after radiation therapy for brain tumor did not show higher accumulation on 201Tl-SPECT, though one patient showed enhanced lesion on X-CT. 201Tl-SPECT was expected to evaluate viability of brain tumor. 123I-IMP-SPECT was useful to recognize the site of higher 201Tl accumulation and evaluate blood flow around brain tumor. It is concluded that 201Tl, 123I-IMP-SPECT is useful for the evaluation of treatment effect of brain tumor and for the differentiation of cerebral radiation injury from recurrent tumor.

Adult↗